diff --git a/.circleci/config.yml b/.circleci/config.yml
index a871be1eb..84e4ac74e 100644
--- a/.circleci/config.yml
+++ b/.circleci/config.yml
@@ -31,7 +31,7 @@ jobs:
       - attach_workspace:
           at: ~/react-native-cli
       - run: |
-          # yarn lint – disable temporarily until ESLint is added to the project
+          yarn lint
           yarn flow-check
   tests:
     <<: *defaults
diff --git a/.eslintignore b/.eslintignore
new file mode 100644
index 000000000..3b29e03f2
--- /dev/null
+++ b/.eslintignore
@@ -0,0 +1,4 @@
+**/node_modules/**
+**/debugger-ui/**
+**/templates/**
+**/global-cli/**
diff --git a/package.json b/package.json
index 1e802249d..c0ccdf98b 100644
--- a/package.json
+++ b/package.json
@@ -5,6 +5,18 @@
   ],
   "scripts": {
     "test": "cd packages/local-cli && yarn jest; cd -",
+    "lint": "eslint packages",
     "flow-check": "cd packages/local-cli && yarn flow check; cd -"
+  },
+  "devDependencies": {
+    "@callstack/eslint-config": "^3.0.2",
+    "eslint": "^5.10.0"
+  },
+  "eslintConfig": {
+    "extends": "@callstack",
+    "rules": {
+      "global-require": 0,
+      "no-console": 0
+    }
   }
 }
diff --git a/packages/local-cli/__mocks__/beeper.js b/packages/local-cli/__mocks__/beeper.js
index 9fbb40caa..f2d46e51f 100644
--- a/packages/local-cli/__mocks__/beeper.js
+++ b/packages/local-cli/__mocks__/beeper.js
@@ -7,9 +7,7 @@
  * @format
  */
 
-'use strict';
-
 // beeper@1.1.0 has a return statement outside of a function
 // and therefore doesn't parse. Let's mock it so that we can
 // run the tests.
-module.exports = function() {};
+module.exports = function beeper() {};
diff --git a/packages/local-cli/__mocks__/fs.js b/packages/local-cli/__mocks__/fs.js
index a3691e3f3..a449fb685 100644
--- a/packages/local-cli/__mocks__/fs.js
+++ b/packages/local-cli/__mocks__/fs.js
@@ -3,37 +3,34 @@
  *
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
- *
- * @format
  */
 
-'use strict';
-
 const path = require('path');
 const MemoryFS = require('metro-memory-fs');
+
 let fs;
 
 function setMockFilesystem(object, platform) {
   reset(platform);
   const root = platform === 'win32' ? 'c:\\' : '/';
-  mockDir(root, {...object});
+  mockDir(root, { ...object });
   return root;
 }
 
 function mockDir(dirPath, desc) {
-  for (const entName in desc) {
+  for (const entName of Object.keys(desc)) {
     const ent = desc[entName];
     const entPath = path.join(dirPath, entName);
     if (typeof ent === 'string' || ent instanceof Buffer) {
       fs.writeFileSync(entPath, ent);
-      continue;
+      continue; // eslint-disable-line no-continue
     }
     if (typeof ent !== 'object') {
       throw new Error(require('util').format('invalid entity:', ent));
     }
     if (ent.SYMLINK != null) {
       fs.symlinkSync(ent.SYMLINK, entPath);
-      continue;
+      continue; // eslint-disable-line no-continue
     }
     fs.mkdirSync(entPath);
     mockDir(entPath, ent);
@@ -43,18 +40,18 @@ function mockDir(dirPath, desc) {
 function reset(platform) {
   if (path.mock == null) {
     throw new Error(
-      'to use this "fs" module mock, you must also mock the "path" module',
+      'to use this "fs" module mock, you must also mock the "path" module'
     );
   }
   path.mock.reset(platform);
   const cwd = () => (platform === 'win32' ? 'c:\\' : '/');
-  fs = new MemoryFS({platform, cwd});
+  fs = new MemoryFS({ platform, cwd });
   Object.assign(mockFs, fs);
 }
 
 const mockFs = {};
 mockFs.__setMockFilesystem = setMockFilesystem;
-mockFs.mock = {clear: reset};
+mockFs.mock = { clear: reset };
 
 reset('posix');
 
diff --git a/packages/local-cli/__mocks__/path.js b/packages/local-cli/__mocks__/path.js
index 813a2525c..884f26590 100644
--- a/packages/local-cli/__mocks__/path.js
+++ b/packages/local-cli/__mocks__/path.js
@@ -7,15 +7,13 @@
  * @format
  */
 
-'use strict';
-
 const mockPath = {};
 
 function reset(platform) {
   Object.assign(mockPath, jest.requireActual('path')[platform]);
 }
 
-mockPath.mock = {reset};
+mockPath.mock = { reset };
 
 reset('posix');
 
diff --git a/packages/local-cli/babel.config.js b/packages/local-cli/babel.config.js
index e3f02bd9b..6f23a5715 100644
--- a/packages/local-cli/babel.config.js
+++ b/packages/local-cli/babel.config.js
@@ -1,4 +1,3 @@
-const path = require('path');
 const escapeRegExp = require('escape-string-regexp');
 
 module.exports = {
@@ -12,7 +11,6 @@ module.exports = {
     ],
     require.resolve('@babel/preset-flow'),
   ],
-  only: [
-    new RegExp('^' + escapeRegExp(__dirname))
-  ]
+  plugins: [require.resolve('@babel/plugin-transform-strict-mode')],
+  only: [new RegExp(`^${escapeRegExp(__dirname)}`)],
 };
diff --git a/packages/local-cli/bin.js b/packages/local-cli/bin.js
index 74b48b754..836285971 100755
--- a/packages/local-cli/bin.js
+++ b/packages/local-cli/bin.js
@@ -17,12 +17,12 @@ if (isInstalledGlobally()) {
   console.error(
     [
       chalk.red(
-        'Looks like you installed react-native globally, maybe you meant react-native-cli?',
+        'Looks like you installed react-native globally, maybe you meant react-native-cli?'
       ),
       chalk.red('To fix the issue, run:'),
       'npm uninstall -g react-native',
       'npm install -g react-native-cli',
-    ].join('\n'),
+    ].join('\n')
   );
   process.exit(1);
 } else {
diff --git a/packages/local-cli/bundle/__mocks__/sign.js b/packages/local-cli/bundle/__mocks__/sign.js
index 31fda82f5..0b8c3a132 100644
--- a/packages/local-cli/bundle/__mocks__/sign.js
+++ b/packages/local-cli/bundle/__mocks__/sign.js
@@ -7,8 +7,6 @@
  * @format
  */
 
-'use strict';
-
 function sign(source) {
   return source;
 }
diff --git a/packages/local-cli/bundle/__tests__/filterPlatformAssetScales-test.js b/packages/local-cli/bundle/__tests__/filterPlatformAssetScales-test.js
index ca336d8fd..120e3b741 100644
--- a/packages/local-cli/bundle/__tests__/filterPlatformAssetScales-test.js
+++ b/packages/local-cli/bundle/__tests__/filterPlatformAssetScales-test.js
@@ -8,8 +8,6 @@
  * @emails oncall+javascript_foundation
  */
 
-'use strict';
-
 jest.dontMock('../filterPlatformAssetScales').dontMock('../assetPathUtils');
 
 const filterPlatformAssetScales = require('../filterPlatformAssetScales');
diff --git a/packages/local-cli/bundle/__tests__/getAssetDestPathAndroid-test.js b/packages/local-cli/bundle/__tests__/getAssetDestPathAndroid-test.js
index 792e2676c..a2625b5d5 100644
--- a/packages/local-cli/bundle/__tests__/getAssetDestPathAndroid-test.js
+++ b/packages/local-cli/bundle/__tests__/getAssetDestPathAndroid-test.js
@@ -8,13 +8,10 @@
  * @emails oncall+javascript_foundation
  */
 
-'use strict';
-
 jest.dontMock('../getAssetDestPathAndroid').dontMock('../assetPathUtils');
 
-const getAssetDestPathAndroid = require('../getAssetDestPathAndroid');
-
 const path = require('path');
+const getAssetDestPathAndroid = require('../getAssetDestPathAndroid');
 
 describe('getAssetDestPathAndroid', () => {
   it('should use the right destination folder', () => {
@@ -24,10 +21,10 @@ describe('getAssetDestPathAndroid', () => {
       httpServerLocation: '/assets/test',
     };
 
-    const expectDestPathForScaleToStartWith = (scale, path) => {
-      if (!getAssetDestPathAndroid(asset, scale).startsWith(path)) {
+    const expectDestPathForScaleToStartWith = (scale, location) => {
+      if (!getAssetDestPathAndroid(asset, scale).startsWith(location)) {
         throw new Error(
-          `asset for scale ${scale} should start with path '${path}'`,
+          `asset for scale ${scale} should start with path '${location}'`
         );
       }
     };
@@ -47,7 +44,7 @@ describe('getAssetDestPathAndroid', () => {
     };
 
     expect(getAssetDestPathAndroid(asset, 1)).toBe(
-      path.normalize('drawable-mdpi/app_test_icon.png'),
+      path.normalize('drawable-mdpi/app_test_icon.png')
     );
   });
 
@@ -69,7 +66,7 @@ describe('getAssetDestPathAndroid', () => {
     };
 
     expect(getAssetDestPathAndroid(asset, 1)).toBe(
-      path.normalize('raw/app_test_video.mp4'),
+      path.normalize('raw/app_test_video.mp4')
     );
   });
 });
diff --git a/packages/local-cli/bundle/__tests__/getAssetDestPathIOS-test.js b/packages/local-cli/bundle/__tests__/getAssetDestPathIOS-test.js
index fb05ba3fb..58bdb37b9 100644
--- a/packages/local-cli/bundle/__tests__/getAssetDestPathIOS-test.js
+++ b/packages/local-cli/bundle/__tests__/getAssetDestPathIOS-test.js
@@ -8,12 +8,10 @@
  * @emails oncall+javascript_foundation
  */
 
-'use strict';
-
 jest.dontMock('../getAssetDestPathIOS');
 
-const getAssetDestPathIOS = require('../getAssetDestPathIOS');
 const path = require('path');
+const getAssetDestPathIOS = require('../getAssetDestPathIOS');
 
 describe('getAssetDestPathIOS', () => {
   it('should build correct path', () => {
@@ -24,7 +22,7 @@ describe('getAssetDestPathIOS', () => {
     };
 
     expect(getAssetDestPathIOS(asset, 1)).toBe(
-      path.normalize('assets/test/icon.png'),
+      path.normalize('assets/test/icon.png')
     );
   });
 
@@ -36,10 +34,10 @@ describe('getAssetDestPathIOS', () => {
     };
 
     expect(getAssetDestPathIOS(asset, 2)).toBe(
-      path.normalize('assets/test/icon@2x.png'),
+      path.normalize('assets/test/icon@2x.png')
     );
     expect(getAssetDestPathIOS(asset, 3)).toBe(
-      path.normalize('assets/test/icon@3x.png'),
+      path.normalize('assets/test/icon@3x.png')
     );
   });
 });
diff --git a/packages/local-cli/bundle/assetPathUtils.js b/packages/local-cli/bundle/assetPathUtils.js
index 7e71e8e13..24aa8344f 100644
--- a/packages/local-cli/bundle/assetPathUtils.js
+++ b/packages/local-cli/bundle/assetPathUtils.js
@@ -8,8 +8,6 @@
  * @flow strict
  */
 
-'use strict';
-
 export type PackagerAsset = {
   +httpServerLocation: string,
   +name: string,
@@ -34,8 +32,9 @@ function getAndroidAssetSuffix(scale: number): string {
       return 'xxhdpi';
     case 4:
       return 'xxxhdpi';
+    default:
+      throw new Error('no such scale');
   }
-  throw new Error('no such scale');
 }
 
 // See https://developer.android.com/guide/topics/resources/drawable-resource.html
@@ -53,20 +52,21 @@ function getAndroidResourceFolderName(asset: PackagerAsset, scale: number) {
   if (!drawableFileTypes.has(asset.type)) {
     return 'raw';
   }
-  var suffix = getAndroidAssetSuffix(scale);
+  const suffix = getAndroidAssetSuffix(scale);
   if (!suffix) {
     throw new Error(
-      "Don't know which android drawable suffix to use for asset: " +
-        JSON.stringify(asset),
+      `Don't know which android drawable suffix to use for asset: ${JSON.stringify(
+        asset
+      )}`
     );
   }
-  const androidFolder = 'drawable-' + suffix;
+  const androidFolder = `drawable-${suffix}`;
   return androidFolder;
 }
 
 function getAndroidResourceIdentifier(asset: PackagerAsset) {
-  var folderPath = getBasePath(asset);
-  return (folderPath + '/' + asset.name)
+  const folderPath = getBasePath(asset);
+  return `${folderPath}/${asset.name}`
     .toLowerCase()
     .replace(/\//g, '_') // Encode folder structure in file name
     .replace(/([^a-z0-9_])/g, '') // Remove illegal chars
@@ -74,7 +74,7 @@ function getAndroidResourceIdentifier(asset: PackagerAsset) {
 }
 
 function getBasePath(asset: PackagerAsset) {
-  var basePath = asset.httpServerLocation;
+  let basePath = asset.httpServerLocation;
   if (basePath[0] === '/') {
     basePath = basePath.substr(1);
   }
@@ -82,8 +82,8 @@ function getBasePath(asset: PackagerAsset) {
 }
 
 module.exports = {
-  getAndroidAssetSuffix: getAndroidAssetSuffix,
-  getAndroidResourceFolderName: getAndroidResourceFolderName,
-  getAndroidResourceIdentifier: getAndroidResourceIdentifier,
-  getBasePath: getBasePath,
+  getAndroidAssetSuffix,
+  getAndroidResourceFolderName,
+  getAndroidResourceIdentifier,
+  getBasePath,
 };
diff --git a/packages/local-cli/bundle/buildBundle.js b/packages/local-cli/bundle/buildBundle.js
index 909dfe687..8859bba6e 100644
--- a/packages/local-cli/bundle/buildBundle.js
+++ b/packages/local-cli/bundle/buildBundle.js
@@ -4,27 +4,29 @@
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
  *
- * @format
+ * @flow
  */
 
-'use strict';
+import type { ContextT } from '../core/types.flow';
+import type { CommandLineArgs } from './bundleCommandLineArgs';
 
-const log = require('../util/log').out('bundle');
 const Server = require('metro/src/Server');
 
 const outputBundle = require('metro/src/shared/output/bundle');
 const path = require('path');
+const log = require('./log').out('bundle');
 const saveAssets = require('./saveAssets');
 
 const loadMetroConfig = require('../util/loadMetroConfig');
 
-import type { ContextT } from '../core/types.flow';
-import type { CommandLineArgs } from './bundleCommandLineArgs';
-
-async function buildBundle(args: CommandLineArgs, ctx: ContextT, output = outputBundle) {
+async function buildBundle(
+  args: CommandLineArgs,
+  ctx: ContextT,
+  output = outputBundle
+) {
   const config = await loadMetroConfig(ctx.root, {
     resetCache: args.resetCache,
-    config: args.config
+    config: args.config,
   });
 
   // This is used by a bazillion of npm modules we don't control so we don't
diff --git a/packages/local-cli/bundle/bundle.js b/packages/local-cli/bundle/bundle.js
index 2eb039044..f0642598e 100644
--- a/packages/local-cli/bundle/bundle.js
+++ b/packages/local-cli/bundle/bundle.js
@@ -7,11 +7,8 @@
  * @format
  */
 
-'use strict';
-
 const buildBundle = require('./buildBundle');
 const bundleCommandLineArgs = require('./bundleCommandLineArgs');
-const outputBundle = require('metro/src/shared/output/bundle');
 
 /**
  * Builds the bundle starting to look for dependencies at the given entry path.
diff --git a/packages/local-cli/bundle/bundleCommandLineArgs.js b/packages/local-cli/bundle/bundleCommandLineArgs.js
index 3d70b2e11..7d3e9abfc 100644
--- a/packages/local-cli/bundle/bundleCommandLineArgs.js
+++ b/packages/local-cli/bundle/bundleCommandLineArgs.js
@@ -7,8 +7,6 @@
  * @flow
  */
 
-'use strict';
-
 const path = require('path');
 
 export type CommandLineArgs = {
@@ -48,7 +46,7 @@ module.exports = [
   {
     command: '--dev [boolean]',
     description: 'If false, warnings are disabled and the bundle is minified',
-    parse: (val: string) => (val === 'false' ? false : true),
+    parse: (val: string) => val !== 'false',
     default: true,
   },
   {
@@ -57,7 +55,7 @@ module.exports = [
       'Allows overriding whether bundle is minified. This defaults to ' +
       'false if dev is true, and true if dev is false. Disabling minification ' +
       'can be useful for speeding up production builds for testing purposes.',
-    parse: (val: string) => (val === 'false' ? false : true),
+    parse: (val: string) => val !== 'false',
   },
   {
     command: '--bundle-output <string>',
diff --git a/packages/local-cli/bundle/filterPlatformAssetScales.js b/packages/local-cli/bundle/filterPlatformAssetScales.js
index d75512e86..681cc6cef 100644
--- a/packages/local-cli/bundle/filterPlatformAssetScales.js
+++ b/packages/local-cli/bundle/filterPlatformAssetScales.js
@@ -8,15 +8,13 @@
  * @format
  */
 
-'use strict';
-
 const ALLOWED_SCALES = {
   ios: [1, 2, 3],
 };
 
 function filterPlatformAssetScales(
   platform: string,
-  scales: $ReadOnlyArray<number>,
+  scales: $ReadOnlyArray<number>
 ): $ReadOnlyArray<number> {
   const whitelist = ALLOWED_SCALES[platform];
   if (!whitelist) {
diff --git a/packages/local-cli/bundle/getAssetDestPathAndroid.js b/packages/local-cli/bundle/getAssetDestPathAndroid.js
index 91e71d623..ff7576dfa 100644
--- a/packages/local-cli/bundle/getAssetDestPathAndroid.js
+++ b/packages/local-cli/bundle/getAssetDestPathAndroid.js
@@ -8,20 +8,18 @@
  * @flow strict
  */
 
-'use strict';
+import type { PackagerAsset } from './assetPathUtils';
 
-const assetPathUtils = require('./assetPathUtils');
 const path = require('path');
-
-import type { PackagerAsset } from './assetPathUtils';
+const assetPathUtils = require('./assetPathUtils');
 
 function getAssetDestPathAndroid(asset: PackagerAsset, scale: number): string {
   const androidFolder = assetPathUtils.getAndroidResourceFolderName(
     asset,
-    scale,
+    scale
   );
   const fileName = assetPathUtils.getAndroidResourceIdentifier(asset);
-  return path.join(androidFolder, fileName + '.' + asset.type);
+  return path.join(androidFolder, `${fileName}.${asset.type}`);
 }
 
 module.exports = getAssetDestPathAndroid;
diff --git a/packages/local-cli/bundle/getAssetDestPathIOS.js b/packages/local-cli/bundle/getAssetDestPathIOS.js
index ba0b65a1f..3978b8a97 100644
--- a/packages/local-cli/bundle/getAssetDestPathIOS.js
+++ b/packages/local-cli/bundle/getAssetDestPathIOS.js
@@ -8,15 +8,13 @@
  * @flow strict
  */
 
-'use strict';
+import type { PackagerAsset } from './assetPathUtils';
 
 const path = require('path');
 
-import type { PackagerAsset } from './assetPathUtils';
-
 function getAssetDestPathIOS(asset: PackagerAsset, scale: number): string {
-  const suffix = scale === 1 ? '' : '@' + scale + 'x';
-  const fileName = asset.name + suffix + '.' + asset.type;
+  const suffix = scale === 1 ? '' : `@${scale}x`;
+  const fileName = `${asset.name + suffix}.${asset.type}`;
   return path.join(asset.httpServerLocation.substr(1), fileName);
 }
 
diff --git a/packages/local-cli/util/log.js b/packages/local-cli/bundle/log.js
similarity index 72%
rename from packages/local-cli/util/log.js
rename to packages/local-cli/bundle/log.js
index e74d74f18..cc32a941d 100644
--- a/packages/local-cli/util/log.js
+++ b/packages/local-cli/bundle/log.js
@@ -7,21 +7,19 @@
  * @format
  */
 
-'use strict';
-
-var _enabled = true;
+let _enabled = true;
 
 function disable() {
   _enabled = false;
 }
 
 function log(stream, module) {
-  return function() {
+  return (...args) => {
     if (!_enabled) {
       return;
     }
-    const message = Array.prototype.slice.call(arguments).join(' ');
-    stream.write(module + ': ' + message + '\n');
+    const message = Array.prototype.slice.call(args).join(' ');
+    stream.write(`${module}: ${message}\n`);
   };
 }
 
diff --git a/packages/local-cli/bundle/ramBundle.js b/packages/local-cli/bundle/ramBundle.js
index 796389034..1697bfa30 100644
--- a/packages/local-cli/bundle/ramBundle.js
+++ b/packages/local-cli/bundle/ramBundle.js
@@ -6,12 +6,10 @@
  *
  * @format
  */
-
-'use strict';
+const outputUnbundle = require('metro/src/shared/output/RamBundle');
 
 const bundleWithOutput = require('./bundle').withOutput;
 const bundleCommandLineArgs = require('./bundleCommandLineArgs');
-const outputUnbundle = require('metro/src/shared/output/RamBundle');
 
 /**
  * Builds the bundle starting to look for dependencies at the given entry path.
diff --git a/packages/local-cli/bundle/saveAssets.js b/packages/local-cli/bundle/saveAssets.js
index d43197ec5..ff1e1b953 100644
--- a/packages/local-cli/bundle/saveAssets.js
+++ b/packages/local-cli/bundle/saveAssets.js
@@ -7,15 +7,14 @@
  * @format
  */
 
-'use strict';
+const mkdirp = require('mkdirp');
+const path = require('path');
+const fs = require('fs');
 
 const filterPlatformAssetScales = require('./filterPlatformAssetScales');
-const fs = require('fs');
 const getAssetDestPathAndroid = require('./getAssetDestPathAndroid');
 const getAssetDestPathIOS = require('./getAssetDestPathIOS');
-const log = require('../util/log').out('bundle');
-const mkdirp = require('mkdirp');
-const path = require('path');
+const log = require('./log').out('bundle');
 
 function saveAssets(assets, platform, assetsDest) {
   if (!assetsDest) {
@@ -29,7 +28,7 @@ function saveAssets(assets, platform, assetsDest) {
   const filesToCopy = Object.create(null); // Map src -> dest
   assets.forEach(asset => {
     const validScales = new Set(
-      filterPlatformAssetScales(platform, asset.scales),
+      filterPlatformAssetScales(platform, asset.scales)
     );
     asset.scales.forEach((scale, idx) => {
       if (!validScales.has(scale)) {
@@ -50,11 +49,12 @@ function copyAll(filesToCopy) {
     return Promise.resolve();
   }
 
-  log('Copying ' + queue.length + ' asset files');
+  log(`Copying ${queue.length} asset files`);
   return new Promise((resolve, reject) => {
     const copyNext = error => {
       if (error) {
-        return reject(error);
+        reject(error);
+        return;
       }
       if (queue.length === 0) {
         log('Done copying assets');
@@ -73,7 +73,8 @@ function copy(src, dest, callback) {
   const destDir = path.dirname(dest);
   mkdirp(destDir, err => {
     if (err) {
-      return callback(err);
+      callback(err);
+      return;
     }
     fs.createReadStream(src)
       .pipe(fs.createWriteStream(dest))
diff --git a/packages/local-cli/cli.js b/packages/local-cli/cli.js
index bd23859ff..5bd3a473f 100644
--- a/packages/local-cli/cli.js
+++ b/packages/local-cli/cli.js
@@ -7,13 +7,12 @@
  * @format
  */
 
-'use strict';
-
 // gracefulify() has to be called before anything else runs
 require('graceful-fs').gracefulify(require('fs'));
 
 // Transpile the source code
 const babelConfig = require('./babel.config');
+
 require('@babel/register')(babelConfig);
 
 const cli = require('./cliEntry');
diff --git a/packages/local-cli/cliEntry.js b/packages/local-cli/cliEntry.js
index a0992550b..5df8dec07 100644
--- a/packages/local-cli/cliEntry.js
+++ b/packages/local-cli/cliEntry.js
@@ -8,21 +8,19 @@
  * @flow
  */
 
-'use strict';
+import type { CommandT, ContextT } from './core/types.flow';
 
-const assertRequiredOptions = require('./util/assertRequiredOptions');
 const chalk = require('chalk');
 const childProcess = require('child_process');
 const commander = require('commander');
+const minimist = require('minimist');
+const path = require('path');
 const getCommands = require('./core/getCommands');
 const getLegacyConfig = require('./core/getLegacyConfig');
-const minimist = require('minimist');
 const init = require('./init/init');
-const path = require('path');
+const assertRequiredOptions = require('./util/assertRequiredOptions');
 const pkg = require('./package.json');
 
-import type { CommandT, ContextT } from './core/types.flow';
-
 commander.version(pkg.version);
 
 const defaultOptParser = val => val;
@@ -43,7 +41,7 @@ const handleError = err => {
 function printHelpInformation() {
   let cmdName = this._name;
   if (this._alias) {
-    cmdName = cmdName + '|' + this._alias;
+    cmdName = `${cmdName}|${this._alias}`;
   }
 
   const sourceInformation = this.pkg
@@ -85,10 +83,10 @@ function printUnknownCommand(cmdName) {
         ? chalk.red(`  Unrecognized command '${cmdName}'`)
         : chalk.red("  You didn't pass any command"),
       `  Run ${chalk.cyan(
-        'react-native --help',
+        'react-native --help'
       )} to see list of all available commands`,
       '',
-    ].join('\n'),
+    ].join('\n')
   );
 }
 
@@ -100,9 +98,9 @@ const addCommand = (command: CommandT, ctx: ContextT) => {
       noHelp: !command.description,
     })
     .description(command.description)
-    .action(function runAction() {
+    .action(function handleAction(...args) {
       const passedOptions = this.opts();
-      const argv: Array<string> = Array.from(arguments).slice(0, -1);
+      const argv: Array<string> = Array.from(args).slice(0, -1);
 
       Promise.resolve()
         .then(() => {
@@ -122,10 +120,10 @@ const addCommand = (command: CommandT, ctx: ContextT) => {
       opt.command,
       opt.description,
       opt.parse || defaultOptParser,
-      typeof opt.default === 'function' ? opt.default(ctx) : opt.default,
-    ),
+      typeof opt.default === 'function' ? opt.default(ctx) : opt.default
+    )
   );
-  
+
   // This is needed to avoid `unknown option` error by Commander.js
   cmd.option('--projectRoot [string]', 'Path to the root of the project');
 };
@@ -139,7 +137,7 @@ async function run() {
 
   /**
    * Read passed `options` and take the "global" settings
-   * 
+   *
    * @todo(grabbou): Consider unifying this by removing either `commander`
    * or `minimist`
    */
@@ -161,7 +159,7 @@ async function run() {
   commander.parse(process.argv);
 
   const isValidCommand = commands.find(
-    cmd => cmd.name.split(' ')[0] === process.argv[2],
+    cmd => cmd.name.split(' ')[0] === process.argv[2]
   );
 
   if (!isValidCommand) {
@@ -175,6 +173,6 @@ async function run() {
 }
 
 module.exports = {
-  run: run,
-  init: init,
+  run,
+  init,
 };
diff --git a/packages/local-cli/core/__fixtures__/android.js b/packages/local-cli/core/__fixtures__/android.js
index d5f603069..d6097b0bf 100644
--- a/packages/local-cli/core/__fixtures__/android.js
+++ b/packages/local-cli/core/__fixtures__/android.js
@@ -11,10 +11,10 @@ const fs = jest.requireActual('fs');
 const path = jest.requireActual('path');
 
 const manifest = fs.readFileSync(
-  path.join(__dirname, './files/AndroidManifest.xml'),
+  path.join(__dirname, './files/AndroidManifest.xml')
 );
 const mainJavaClass = fs.readFileSync(
-  path.join(__dirname, './files/Main.java'),
+  path.join(__dirname, './files/Main.java')
 );
 
 function generateValidFileStructure(classFileName) {
@@ -27,7 +27,7 @@ function generateValidFileStructure(classFileName) {
             example: {
               'Main.java': mainJavaClass,
               [classFileName]: fs.readFileSync(
-                path.join(__dirname, `./files/${classFileName}`),
+                path.join(__dirname, `./files/${classFileName}`)
               ),
             },
           },
@@ -50,7 +50,7 @@ exports.userConfigManifest = {
           example: {
             'Main.java': mainJavaClass,
             'ReactPackage.java': fs.readFileSync(
-              path.join(__dirname, './files/ReactPackage.java'),
+              path.join(__dirname, './files/ReactPackage.java')
             ),
           },
         },
@@ -58,7 +58,7 @@ exports.userConfigManifest = {
     },
     debug: {
       'AndroidManifest.xml': fs.readFileSync(
-        path.join(__dirname, './files/AndroidManifest-debug.xml'),
+        path.join(__dirname, './files/AndroidManifest-debug.xml')
       ),
     },
   },
diff --git a/packages/local-cli/core/__fixtures__/ios.js b/packages/local-cli/core/__fixtures__/ios.js
index 1792f6730..eb043ea11 100644
--- a/packages/local-cli/core/__fixtures__/ios.js
+++ b/packages/local-cli/core/__fixtures__/ios.js
@@ -13,7 +13,7 @@ const path = require('path');
 exports.valid = {
   'demoProject.xcodeproj': {
     'project.pbxproj': fs.readFileSync(
-      path.join(__dirname, './files/project.pbxproj'),
+      path.join(__dirname, './files/project.pbxproj')
     ),
   },
   'TestPod.podspec': 'empty',
@@ -22,7 +22,7 @@ exports.valid = {
 exports.validTestName = {
   'MyTestProject.xcodeproj': {
     'project.pbxproj': fs.readFileSync(
-      path.join(__dirname, './files/project.pbxproj'),
+      path.join(__dirname, './files/project.pbxproj')
     ),
   },
 };
diff --git a/packages/local-cli/core/__fixtures__/projects.js b/packages/local-cli/core/__fixtures__/projects.js
index c3d42d693..a3e8d0b67 100644
--- a/packages/local-cli/core/__fixtures__/projects.js
+++ b/packages/local-cli/core/__fixtures__/projects.js
@@ -34,4 +34,4 @@ const withPods = {
   ios: ios.pod,
 };
 
-module.exports = {flat, nested, withExamples, withPods};
+module.exports = { flat, nested, withExamples, withPods };
diff --git a/packages/local-cli/core/__tests__/android/findAndroidAppFolder-test.js b/packages/local-cli/core/__tests__/android/findAndroidAppFolder-test.js
index 331dfe8e1..2eb8d9a7b 100644
--- a/packages/local-cli/core/__tests__/android/findAndroidAppFolder-test.js
+++ b/packages/local-cli/core/__tests__/android/findAndroidAppFolder-test.js
@@ -8,8 +8,6 @@
  * @emails oncall+javascript_foundation
  */
 
-'use strict';
-
 jest.mock('path');
 jest.mock('fs');
 
diff --git a/packages/local-cli/core/__tests__/android/findManifest-test.js b/packages/local-cli/core/__tests__/android/findManifest-test.js
index 242b20a74..d1dc608d8 100644
--- a/packages/local-cli/core/__tests__/android/findManifest-test.js
+++ b/packages/local-cli/core/__tests__/android/findManifest-test.js
@@ -8,13 +8,11 @@
  * @emails oncall+javascript_foundation
  */
 
-'use strict';
-
 jest.mock('path');
 jest.mock('fs');
 
-const findManifest = require('../../android/findManifest');
 const fs = require('fs');
+const findManifest = require('../../android/findManifest');
 const mocks = require('../../__fixtures__/android');
 
 describe('android::findManifest', () => {
diff --git a/packages/local-cli/core/__tests__/android/findPackageClassName-test.js b/packages/local-cli/core/__tests__/android/findPackageClassName-test.js
index 5c15fd658..251b7e988 100644
--- a/packages/local-cli/core/__tests__/android/findPackageClassName-test.js
+++ b/packages/local-cli/core/__tests__/android/findPackageClassName-test.js
@@ -8,14 +8,12 @@
  * @emails oncall+javascript_foundation
  */
 
-'use strict';
-
 jest.mock('path');
 jest.mock('fs');
 
+const fs = require('fs');
 const mocks = require('../../__fixtures__/android');
 const findPackageClassName = require('../../android/findPackageClassName');
-const fs = require('fs');
 
 ['posix', 'win32'].forEach(platform => {
   let root;
@@ -31,28 +29,28 @@ const fs = require('fs');
             android: mocks.validKotlin,
           },
         },
-        platform,
+        platform
       );
     });
 
     it('returns manifest content if file exists in the folder', () => {
-      expect(typeof findPackageClassName(root + 'flatJava')).toBe('string');
+      expect(typeof findPackageClassName(`${root}flatJava`)).toBe('string');
     });
 
     it('returns the name of the java class implementing ReactPackage', () => {
-      expect(findPackageClassName(root + 'flatJava')).toBe(
-        'SomeExampleJavaPackage',
+      expect(findPackageClassName(`${root}flatJava`)).toBe(
+        'SomeExampleJavaPackage'
       );
     });
 
     it('returns the name of the kotlin class implementing ReactPackage', () => {
-      expect(findPackageClassName(root + 'flatKotlin')).toBe(
-        'SomeExampleKotlinPackage',
+      expect(findPackageClassName(`${root}flatKotlin`)).toBe(
+        'SomeExampleKotlinPackage'
       );
     });
 
     it('returns `null` if there are no matches', () => {
-      expect(findPackageClassName(root + 'empty')).toBeNull();
+      expect(findPackageClassName(`${root}empty`)).toBeNull();
     });
   });
 });
diff --git a/packages/local-cli/core/__tests__/android/getDependencyConfig-test.js b/packages/local-cli/core/__tests__/android/getDependencyConfig-test.js
index 7a43db319..f8fcb0017 100644
--- a/packages/local-cli/core/__tests__/android/getDependencyConfig-test.js
+++ b/packages/local-cli/core/__tests__/android/getDependencyConfig-test.js
@@ -8,13 +8,12 @@
  * @emails oncall+javascript_foundation
  */
 
-'use strict';
-
 jest.mock('path');
 jest.mock('fs');
 
-const getDependencyConfig = require('../../android').dependencyConfig;
 const fs = require('fs');
+
+const getDependencyConfig = require('../../android').dependencyConfig;
 const mocks = require('../../__fixtures__/android');
 
 const userConfig = {};
diff --git a/packages/local-cli/core/__tests__/android/getProjectConfig-test.js b/packages/local-cli/core/__tests__/android/getProjectConfig-test.js
index 863138c95..8fa3b4eb2 100644
--- a/packages/local-cli/core/__tests__/android/getProjectConfig-test.js
+++ b/packages/local-cli/core/__tests__/android/getProjectConfig-test.js
@@ -8,13 +8,12 @@
  * @emails oncall+javascript_foundation
  */
 
-'use strict';
-
 jest.mock('path');
 jest.mock('fs');
 
-const getProjectConfig = require('../../android').projectConfig;
 const fs = require('fs');
+
+const getProjectConfig = require('../../android').projectConfig;
 const mocks = require('../../__fixtures__/android');
 
 describe('android::getProjectConfig', () => {
diff --git a/packages/local-cli/core/__tests__/android/readManifest-test.js b/packages/local-cli/core/__tests__/android/readManifest-test.js
index 2b8f41e4f..bc8379eff 100644
--- a/packages/local-cli/core/__tests__/android/readManifest-test.js
+++ b/packages/local-cli/core/__tests__/android/readManifest-test.js
@@ -8,14 +8,12 @@
  * @emails oncall+javascript_foundation
  */
 
-'use strict';
-
 jest.mock('path');
 jest.mock('fs');
 
+const fs = require('fs');
 const findManifest = require('../../android/findManifest');
 const readManifest = require('../../android/readManifest');
-const fs = require('fs');
 const mocks = require('../../__fixtures__/android');
 
 describe('android::readManifest', () => {
diff --git a/packages/local-cli/core/__tests__/findAssets-test.js b/packages/local-cli/core/__tests__/findAssets-test.js
index bb3a000cc..adaeb8db7 100644
--- a/packages/local-cli/core/__tests__/findAssets-test.js
+++ b/packages/local-cli/core/__tests__/findAssets-test.js
@@ -8,18 +8,17 @@
  * @emails oncall+javascript_foundation
  */
 
-'use strict';
-
 jest.mock('path');
 jest.mock('fs');
 
+const fs = require('fs');
+
 const { findAssets } = require('../getAssets');
 const dependencies = require('../__fixtures__/dependencies');
-const fs = require('fs');
 
 describe('findAssets', () => {
   beforeEach(() => {
-    fs.__setMockFilesystem({testDir: dependencies.withAssets});
+    fs.__setMockFilesystem({ testDir: dependencies.withAssets });
   });
 
   it('returns an array of all files in given folders', () => {
diff --git a/packages/local-cli/core/__tests__/findPlugins-test.js b/packages/local-cli/core/__tests__/findPlugins-test.js
index bf04ddecb..901bd7acf 100644
--- a/packages/local-cli/core/__tests__/findPlugins-test.js
+++ b/packages/local-cli/core/__tests__/findPlugins-test.js
@@ -8,10 +8,8 @@
  * @emails oncall+javascript_foundation
  */
 
-'use strict';
-
-const findPlugins = require('../findPlugins');
 const path = require('path');
+const findPlugins = require('../findPlugins');
 
 const ROOT = path.join(__dirname, '..', '..');
 const pjsonPath = path.join(ROOT, 'package.json');
@@ -23,7 +21,7 @@ describe('findPlugins', () => {
 
   it('returns an array of dependencies', () => {
     jest.mock(pjsonPath, () => ({
-      dependencies: {'rnpm-plugin-test': '*'},
+      dependencies: { 'rnpm-plugin-test': '*' },
     }));
 
     expect(findPlugins(ROOT)).toHaveProperty('commands');
@@ -50,8 +48,8 @@ describe('findPlugins', () => {
 
   it('returns plugins from both dependencies and dev dependencies', () => {
     jest.mock(pjsonPath, () => ({
-      dependencies: {'rnpm-plugin-test': '*'},
-      devDependencies: {'rnpm-plugin-test-2': '*'},
+      dependencies: { 'rnpm-plugin-test': '*' },
+      devDependencies: { 'rnpm-plugin-test-2': '*' },
     }));
     expect(findPlugins(ROOT)).toHaveProperty('commands');
     expect(findPlugins(ROOT)).toHaveProperty('platforms');
@@ -61,8 +59,8 @@ describe('findPlugins', () => {
 
   it('returns unique list of plugins', () => {
     jest.mock(pjsonPath, () => ({
-      dependencies: {'rnpm-plugin-test': '*'},
-      devDependencies: {'rnpm-plugin-test': '*'},
+      dependencies: { 'rnpm-plugin-test': '*' },
+      devDependencies: { 'rnpm-plugin-test': '*' },
     }));
     expect(findPlugins(ROOT).commands).toHaveLength(1);
   });
diff --git a/packages/local-cli/core/__tests__/ios/findPodfilePath-test.js b/packages/local-cli/core/__tests__/ios/findPodfilePath-test.js
index 227d24512..798cb9251 100644
--- a/packages/local-cli/core/__tests__/ios/findPodfilePath-test.js
+++ b/packages/local-cli/core/__tests__/ios/findPodfilePath-test.js
@@ -8,13 +8,11 @@
  * @emails oncall+javascript_foundation
  */
 
-'use strict';
-
 jest.mock('path');
 jest.mock('fs');
 
-const findPodfilePath = require('../../ios/findPodfilePath');
 const fs = require('fs');
+const findPodfilePath = require('../../ios/findPodfilePath');
 const projects = require('../../__fixtures__/projects');
 const ios = require('../../__fixtures__/ios');
 
diff --git a/packages/local-cli/core/__tests__/ios/findPodspecName-test.js b/packages/local-cli/core/__tests__/ios/findPodspecName-test.js
index 14d73cd7d..a54c11abc 100644
--- a/packages/local-cli/core/__tests__/ios/findPodspecName-test.js
+++ b/packages/local-cli/core/__tests__/ios/findPodspecName-test.js
@@ -8,13 +8,11 @@
  * @emails oncall+javascript_foundation
  */
 
-'use strict';
-
 jest.mock('path');
 jest.mock('fs');
 
-const findPodspecName = require('../../ios/findPodspecName');
 const fs = require('fs');
+const findPodspecName = require('../../ios/findPodspecName');
 const projects = require('../../__fixtures__/projects');
 const ios = require('../../__fixtures__/ios');
 
diff --git a/packages/local-cli/core/__tests__/ios/findProject-test.js b/packages/local-cli/core/__tests__/ios/findProject-test.js
index 0083e9bd0..fce47f476 100644
--- a/packages/local-cli/core/__tests__/ios/findProject-test.js
+++ b/packages/local-cli/core/__tests__/ios/findProject-test.js
@@ -8,13 +8,11 @@
  * @emails oncall+javascript_foundation
  */
 
-'use strict';
-
 jest.mock('path');
 jest.mock('fs');
 
-const findProject = require('../../ios/findProject');
 const fs = require('fs');
+const findProject = require('../../ios/findProject');
 const projects = require('../../__fixtures__/projects');
 const ios = require('../../__fixtures__/ios');
 
@@ -25,22 +23,22 @@ describe('ios::findProject', () => {
   });
 
   it('returns null if there are no projects', () => {
-    fs.__setMockFilesystem({testDir: projects});
+    fs.__setMockFilesystem({ testDir: projects });
     expect(findProject('/')).toBeNull();
   });
 
   it('returns ios project regardless of its name', () => {
-    fs.__setMockFilesystem({ios: ios.validTestName});
+    fs.__setMockFilesystem({ ios: ios.validTestName });
     expect(findProject('/')).not.toBeNull();
   });
 
   it('ignores node_modules', () => {
-    fs.__setMockFilesystem({node_modules: projects.flat});
+    fs.__setMockFilesystem({ node_modules: projects.flat });
     expect(findProject('/')).toBeNull();
   });
 
   it('ignores Pods', () => {
-    fs.__setMockFilesystem({Pods: projects.flat});
+    fs.__setMockFilesystem({ Pods: projects.flat });
     expect(findProject('/')).toBeNull();
   });
 
diff --git a/packages/local-cli/core/__tests__/ios/getProjectConfig-test.js b/packages/local-cli/core/__tests__/ios/getProjectConfig-test.js
index d1af61e4b..1ac8ce211 100644
--- a/packages/local-cli/core/__tests__/ios/getProjectConfig-test.js
+++ b/packages/local-cli/core/__tests__/ios/getProjectConfig-test.js
@@ -8,20 +8,19 @@
  * @emails oncall+javascript_foundation
  */
 
-'use strict';
-
 jest.mock('path');
 jest.mock('fs');
 
-const getProjectConfig = require('../../ios').projectConfig;
 const fs = require('fs');
+
+const getProjectConfig = require('../../ios').projectConfig;
 const projects = require('../../__fixtures__/projects');
 
 describe('ios::getProjectConfig', () => {
   const userConfig = {};
 
   beforeEach(() => {
-    fs.__setMockFilesystem({testDir: projects});
+    fs.__setMockFilesystem({ testDir: projects });
   });
 
   it('returns an object with ios project configuration', () => {
diff --git a/packages/local-cli/core/__tests__/makeCommand-test.js b/packages/local-cli/core/__tests__/makeCommand-test.js
index 34a55e6f2..38a076a30 100644
--- a/packages/local-cli/core/__tests__/makeCommand-test.js
+++ b/packages/local-cli/core/__tests__/makeCommand-test.js
@@ -8,8 +8,6 @@
  * @emails oncall+javascript_foundation
  */
 
-'use strict';
-
 let spawnError = false;
 
 jest.setMock('child_process', {
diff --git a/packages/local-cli/core/android/findAndroidAppFolder.js b/packages/local-cli/core/android/findAndroidAppFolder.js
index 41e1319a0..0d8848b36 100644
--- a/packages/local-cli/core/android/findAndroidAppFolder.js
+++ b/packages/local-cli/core/android/findAndroidAppFolder.js
@@ -7,8 +7,6 @@
  * @format
  */
 
-'use strict';
-
 const fs = require('fs');
 const path = require('path');
 
diff --git a/packages/local-cli/core/android/findManifest.js b/packages/local-cli/core/android/findManifest.js
index 4c04ed7cb..1354a85d1 100644
--- a/packages/local-cli/core/android/findManifest.js
+++ b/packages/local-cli/core/android/findManifest.js
@@ -7,8 +7,6 @@
  * @format
  */
 
-'use strict';
-
 const glob = require('glob');
 const path = require('path');
 
diff --git a/packages/local-cli/core/android/findPackageClassName.js b/packages/local-cli/core/android/findPackageClassName.js
index a1bfaf6f2..01436454b 100644
--- a/packages/local-cli/core/android/findPackageClassName.js
+++ b/packages/local-cli/core/android/findPackageClassName.js
@@ -7,8 +7,6 @@
  * @format
  */
 
-'use strict';
-
 const fs = require('fs');
 const glob = require('glob');
 const path = require('path');
@@ -20,7 +18,7 @@ const path = require('path');
  * @param {String} folder Folder to find java/kt files
  */
 module.exports = function getPackageClassName(folder) {
-  const files = glob.sync('**/+(*.java|*.kt)', {cwd: folder});
+  const files = glob.sync('**/+(*.java|*.kt)', { cwd: folder });
 
   const packages = files
     .map(filePath => fs.readFileSync(path.join(folder, filePath), 'utf8'))
diff --git a/packages/local-cli/core/android/index.js b/packages/local-cli/core/android/index.js
index 2106ed7a9..1a674af6a 100644
--- a/packages/local-cli/core/android/index.js
+++ b/packages/local-cli/core/android/index.js
@@ -7,12 +7,10 @@
  * @format
  */
 
-'use strict';
-
+const path = require('path');
 const findAndroidAppFolder = require('./findAndroidAppFolder');
 const findManifest = require('./findManifest');
 const findPackageClassName = require('./findPackageClassName');
-const path = require('path');
 const readManifest = require('./readManifest');
 
 const getPackageName = manifest => manifest.attr.package;
@@ -52,28 +50,28 @@ exports.projectConfig = function projectConfigAndroid(folder, userConfig = {}) {
   const mainFilePath = path.join(
     sourceDir,
     userConfig.mainFilePath ||
-      `src/main/java/${packageFolder}/MainApplication.java`,
+      `src/main/java/${packageFolder}/MainApplication.java`
   );
 
   const stringsPath = path.join(
     sourceDir,
-    userConfig.stringsPath || 'src/main/res/values/strings.xml',
+    userConfig.stringsPath || 'src/main/res/values/strings.xml'
   );
 
   const settingsGradlePath = path.join(
     folder,
     'android',
-    userConfig.settingsGradlePath || 'settings.gradle',
+    userConfig.settingsGradlePath || 'settings.gradle'
   );
 
   const assetsPath = path.join(
     sourceDir,
-    userConfig.assetsPath || 'src/main/assets',
+    userConfig.assetsPath || 'src/main/assets'
   );
 
   const buildGradlePath = path.join(
     sourceDir,
-    userConfig.buildGradlePath || 'build.gradle',
+    userConfig.buildGradlePath || 'build.gradle'
   );
 
   return {
@@ -95,7 +93,7 @@ exports.projectConfig = function projectConfigAndroid(folder, userConfig = {}) {
  */
 exports.dependencyConfig = function dependencyConfigAndroid(
   folder,
-  userConfig = {},
+  userConfig = {}
 ) {
   const src = userConfig.sourceDir || findAndroidAppFolder(folder);
 
@@ -130,7 +128,7 @@ exports.dependencyConfig = function dependencyConfigAndroid(
   const packageInstance =
     userConfig.packageInstance || `new ${packageClassName}()`;
 
-  return {sourceDir, folder, manifest, packageImportPath, packageInstance};
+  return { sourceDir, folder, manifest, packageImportPath, packageInstance };
 };
 
 exports.linkConfig = require('../../link/android');
diff --git a/packages/local-cli/core/android/readManifest.js b/packages/local-cli/core/android/readManifest.js
index 159cb601d..b86cc725f 100644
--- a/packages/local-cli/core/android/readManifest.js
+++ b/packages/local-cli/core/android/readManifest.js
@@ -7,8 +7,6 @@
  * @format
  */
 
-'use strict';
-
 const fs = require('fs');
 const xml = require('xmldoc');
 
diff --git a/packages/local-cli/core/findPlugins.js b/packages/local-cli/core/findPlugins.js
index 3ff90bfc4..43b061a75 100644
--- a/packages/local-cli/core/findPlugins.js
+++ b/packages/local-cli/core/findPlugins.js
@@ -4,15 +4,11 @@
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
  *
- * @format
+ * @flow
  */
 
-'use strict';
-
 const path = require('path');
-const union = require('lodash').union;
-const uniq = require('lodash').uniq;
-const flatten = require('lodash').flatten;
+const { union, uniq, flatten } = require('lodash');
 
 const RNPM_PLUGIN_PATTERNS = [/^rnpm-plugin-/, /^@(.*)\/rnpm-plugin-/];
 
@@ -69,15 +65,17 @@ const findHasteConfigInPackageAndConcat = (pjson, haste) => {
   if (!pjson.rnpm || !pjson.rnpm.haste) {
     return;
   }
-  let pkgHaste = pjson.rnpm.haste;
+  const pkgHaste = pjson.rnpm.haste;
 
   if (pkgHaste.platforms) {
+    // eslint-disable-next-line no-param-reassign
     haste.platforms = haste.platforms.concat(pkgHaste.platforms);
   }
 
   if (pkgHaste.providesModuleNodeModules) {
+    // eslint-disable-next-line no-param-reassign
     haste.providesModuleNodeModules = haste.providesModuleNodeModules.concat(
-      pkgHaste.providesModuleNodeModules,
+      pkgHaste.providesModuleNodeModules
     );
   }
 };
@@ -91,13 +89,11 @@ const findPluginsInFolder = folder => {
 
   const deps = union(
     Object.keys(pjson.dependencies || {}),
-    Object.keys(pjson.devDependencies || {}),
+    Object.keys(pjson.devDependencies || {})
   );
 
   return deps.reduce((acc, pkg) => {
-    let commands = acc.commands;
-    let platforms = acc.platforms;
-    let haste = acc.haste;
+    let { commands, platforms } = acc;
     if (isRNPMPlugin(pkg)) {
       commands = commands.concat(pkg);
     }
@@ -106,10 +102,10 @@ const findPluginsInFolder = folder => {
       if (pkgJson) {
         commands = commands.concat(findPluginsInReactNativePackage(pkgJson));
         platforms = platforms.concat(findPlatformsInPackage(pkgJson));
-        findHasteConfigInPackageAndConcat(pkgJson, haste);
+        findHasteConfigInPackageAndConcat(pkgJson, acc.haste);
       }
     }
-    return {commands: commands, platforms: platforms, haste: haste};
+    return { commands, platforms, haste: acc.haste };
   }, getEmptyPluginConfig());
 };
 
@@ -125,7 +121,7 @@ module.exports = function findPlugins(folder: string) {
     haste: {
       platforms: uniq(flatten(plugin.haste.platforms)),
       providesModuleNodeModules: uniq(
-        flatten(plugin.haste.providesModuleNodeModules),
+        flatten(plugin.haste.providesModuleNodeModules)
       ),
     },
   };
diff --git a/packages/local-cli/core/getAssets.js b/packages/local-cli/core/getAssets.js
index f25ce57df..97fffd78b 100644
--- a/packages/local-cli/core/getAssets.js
+++ b/packages/local-cli/core/getAssets.js
@@ -2,14 +2,12 @@
  * @flow
  */
 
-'use strict';
-
 const glob = require('glob');
 const path = require('path');
 const getPackageConfiguration = require('./getPackageConfiguration');
 
 const findAssetsInFolder = folder =>
-  glob.sync(path.join(folder, '**'), {nodir: true});
+  glob.sync(path.join(folder, '**'), { nodir: true });
 
 /**
  * Given an array of assets folders, e.g. ['Fonts', 'Images'],
@@ -21,10 +19,11 @@ function findAssets(folder, assets) {
   return (assets || [])
     .map(asset => path.join(folder, asset))
     .reduce(
-      (acc, assetPath) => (acc.concat(findAssetsInFolder(assetPath)): Array<string>),
-      [],
+      (acc, assetPath) =>
+        (acc.concat(findAssetsInFolder(assetPath)): Array<string>),
+      []
     );
-};
+}
 
 /**
  * Returns a project configuration in a given folder
diff --git a/packages/local-cli/core/getCommands.js b/packages/local-cli/core/getCommands.js
index 325f678ae..decec9850 100644
--- a/packages/local-cli/core/getCommands.js
+++ b/packages/local-cli/core/getCommands.js
@@ -2,13 +2,10 @@
  * @flow
  */
 
-'use strict';
+import type { CommandT, ProjectCommandT } from './types.flow';
 
-const findPlugins = require('./findPlugins');
 const path = require('path');
-const flatten = require('lodash').flatten;
-
-import type { CommandT, ProjectCommandT } from './types.flow';
+const findPlugins = require('./findPlugins');
 
 /**
  * List of built-in commands
@@ -33,8 +30,8 @@ const loadLocalCommands = () => [
 ];
 
 /**
- * Returns an array of commands that are defined in the project.  
- * 
+ * Returns an array of commands that are defined in the project.
+ *
  * This checks all CLI plugins for presence of 3rd party packages that define commands
  * and loads them
  */
@@ -44,29 +41,35 @@ const loadProjectCommands = (root: string): Array<ProjectCommandT> => {
   return plugins.commands.reduce((acc: Array<CommandT>, pathToCommands) => {
     /**
      * `pathToCommand` is a path to a file where commands are defined, relative to `node_modules`
-     * folder. 
-     * 
+     * folder.
+     *
      * Following code gets the name of the package name out of the path, taking scope
      * into consideration.
      */
     const name =
       pathToCommands[0] === '@'
         ? pathToCommands
-          .split(path.sep)
-          .slice(0, 2)
-          .join(path.sep)
+            .split(path.sep)
+            .slice(0, 2)
+            .join(path.sep)
         : pathToCommands.split(path.sep)[0];
 
     // $FlowFixMe: Non-literal require
     const pkg = require(path.join(root, 'node_modules', name, 'package.json'));
 
     // $FlowFixMe: Non-literal require
-    let requiredCommands: (ProjectCommandT | Array<ProjectCommandT>) = require(
-      path.join(root, 'node_modules', pathToCommands)
-    );
+    const requiredCommands:
+      | ProjectCommandT
+      | Array<ProjectCommandT> = require(path.join(
+      root,
+      'node_modules',
+      pathToCommands
+    ));
 
     if (Array.isArray(requiredCommands)) {
-      return acc.concat(requiredCommands.map(requiredCommand => ({ ...requiredCommand, pkg })));
+      return acc.concat(
+        requiredCommands.map(requiredCommand => ({ ...requiredCommand, pkg }))
+      );
     }
 
     return acc.concat({ ...requiredCommands });
@@ -85,7 +88,7 @@ module.exports = (root: string): Array<CommandT> => [
         [
           'Looks like React Native project already exists in the current',
           'folder. Run this command from a different folder or remove node_modules/react-native',
-        ].join('\n'),
+        ].join('\n')
       );
     },
   },
diff --git a/packages/local-cli/core/getHooks.js b/packages/local-cli/core/getHooks.js
index dafb34de9..84d193073 100644
--- a/packages/local-cli/core/getHooks.js
+++ b/packages/local-cli/core/getHooks.js
@@ -2,16 +2,14 @@
  * @flow
  */
 
-'use strict';
-
-const spawn = require('child_process').spawn;
+const { spawn } = require('child_process');
 const getPackageConfiguration = require('./getPackageConfiguration');
 
 function makeCommand(command) {
   return cb => {
     if (!cb) {
       throw new Error(
-        `You missed a callback function for the ${command} command`,
+        `You missed a callback function for the ${command} command`
       );
     }
 
@@ -23,7 +21,7 @@ function makeCommand(command) {
       stdin: 'inherit',
     });
 
-    commandProcess.on('close', function prelink(code) {
+    commandProcess.on('close', code => {
       if (code) {
         throw new Error(`Error occurred during executing "${command}" command`);
       }
@@ -31,19 +29,18 @@ function makeCommand(command) {
       cb();
     });
   };
-};
+}
 
 module.exports = function getHooks(root: string) {
   const commands = getPackageConfiguration(root).commands || {};
-  
+
   const acc = {};
-  
-  Object.keys(commands)
-    .forEach(command => {
-      acc[command] = makeCommand(commands[command]);
-    });
-  
-    return acc;
+
+  Object.keys(commands).forEach(command => {
+    acc[command] = makeCommand(commands[command]);
+  });
+
+  return acc;
 };
 
 module.exports.makeCommand = makeCommand;
diff --git a/packages/local-cli/core/getLegacyConfig.js b/packages/local-cli/core/getLegacyConfig.js
index a252eaa09..88b61c81a 100644
--- a/packages/local-cli/core/getLegacyConfig.js
+++ b/packages/local-cli/core/getLegacyConfig.js
@@ -10,60 +10,53 @@ const getHooks = require('./getHooks');
 const getAssets = require('./getAssets');
 const getParams = require('./getParams');
 
-const generateDeprecationMessage = (api) => {
-  return `${api} is deprecated and will be removed soon. Please check release notes on how to upgrade`
-};
+const generateDeprecationMessage = api =>
+  `${api} is deprecated and will be removed soon. Please check release notes on how to upgrade`;
 
 /**
  * Gets legacy configuration to support existing plugins while they migrate
  * to the new API
- * 
+ *
  * This file will be removed from the next version.
  */
 module.exports = (root: string) => ({
   getPlatformConfig: util.deprecate(
     () => getPlatforms(root),
-    generateDeprecationMessage("getPlatformConfig()"),
+    generateDeprecationMessage('getPlatformConfig()')
   ),
-  getProjectConfig: util.deprecate(
-    () => {
-      const platforms = getPlatforms(root);
+  getProjectConfig: util.deprecate(() => {
+    const platforms = getPlatforms(root);
 
-      const rnpm = getPackageConfiguration(root); 
+    const rnpm = getPackageConfiguration(root);
 
-      const config = {
-        ...rnpm,
-        assets: getAssets(root),
-      };
+    const config = {
+      ...rnpm,
+      assets: getAssets(root),
+    };
 
-      Object.keys(platforms).forEach(key => {
-        config[key] = platforms[key].projectConfig(root, rnpm[key] || {});
-      });
+    Object.keys(platforms).forEach(key => {
+      config[key] = platforms[key].projectConfig(root, rnpm[key] || {});
+    });
 
-      return config;
-    },
-    generateDeprecationMessage("getProjectConfig()"),
-  ),
-  getDependencyConfig: util.deprecate(
-    (packageName: string) => {
-      const platforms = getPlatforms(root);
-      const folder = path.join(process.cwd(), 'node_modules', packageName);
+    return config;
+  }, generateDeprecationMessage('getProjectConfig()')),
+  getDependencyConfig: util.deprecate((packageName: string) => {
+    const platforms = getPlatforms(root);
+    const folder = path.join(process.cwd(), 'node_modules', packageName);
 
-      const rnpm = getPackageConfiguration(folder);
+    const rnpm = getPackageConfiguration(folder);
 
-      const config = {
-        ...rnpm,
-        assets: getAssets(folder),
-        commands: getHooks(folder),
-        params: getParams(folder),
-      };
+    const config = {
+      ...rnpm,
+      assets: getAssets(folder),
+      commands: getHooks(folder),
+      params: getParams(folder),
+    };
 
-      Object.keys(platforms).forEach(key => {
-        config[key] = platforms[key].dependencyConfig(folder, rnpm[key] || {});
-      });
+    Object.keys(platforms).forEach(key => {
+      config[key] = platforms[key].dependencyConfig(folder, rnpm[key] || {});
+    });
 
-      return config;
-    },
-    generateDeprecationMessage("getDependencyConfig()"),
-  ),
+    return config;
+  }, generateDeprecationMessage('getDependencyConfig()')),
 });
diff --git a/packages/local-cli/core/getPackageConfiguration.js b/packages/local-cli/core/getPackageConfiguration.js
index 656e0f818..e9e46a81f 100644
--- a/packages/local-cli/core/getPackageConfiguration.js
+++ b/packages/local-cli/core/getPackageConfiguration.js
@@ -1,14 +1,16 @@
 /**
  * @flow
  */
-const path = require('path');
-
 import type { PackageConfigurationT } from './types.flow';
 
+const path = require('path');
+
 /**
  * Returns configuration of the CLI from `package.json`.
  */
-module.exports = function getPackageConfiguration(folder: string): PackageConfigurationT {
+module.exports = function getPackageConfiguration(
+  folder: string
+): PackageConfigurationT {
   // $FlowFixMe: Non-literal require
   return require(path.join(folder, './package.json')).rnpm || {};
 };
diff --git a/packages/local-cli/core/getParams.js b/packages/local-cli/core/getParams.js
index 52c985e9d..9dc3d792f 100644
--- a/packages/local-cli/core/getParams.js
+++ b/packages/local-cli/core/getParams.js
@@ -2,8 +2,6 @@
  * @flow
  */
 
-'use strict';
-
 const getPackageConfiguration = require('./getPackageConfiguration');
 
 module.exports = function getParams(root: string) {
diff --git a/packages/local-cli/core/getPlatforms.js b/packages/local-cli/core/getPlatforms.js
index 2d3f22248..718ebc9b5 100644
--- a/packages/local-cli/core/getPlatforms.js
+++ b/packages/local-cli/core/getPlatforms.js
@@ -2,11 +2,14 @@
  * @flow
  */
 
+import type { PlatformsT } from './types.flow';
+
+const path = require('path');
 const findPlugins = require('./findPlugins');
 
 /**
  * Support for `ios` and `android` platforms is built-in
- * 
+ *
  * @todo(grabbou): Move this out of the core to increase "interoperability"
  * with other platforms
  */
@@ -15,8 +18,6 @@ const builtInPlatforms = {
   android: require('./android'),
 };
 
-import type { PlatformsT } from './types.flow';
-
 /**
  * Returns an object with available platforms
  */
@@ -26,20 +27,22 @@ module.exports = function getPlatforms(root: string): PlatformsT {
   /**
    * Each `platfom` is a file that should define an object with platforms available
    * and the config required.
-   * 
+   *
    * @todo(grabbou): We should validate if the config loaded is correct, warn and skip
    * using it if it's invalid.
    */
-  const projectPlatforms = plugins.platforms.reduce((acc, pathToPlatform) => {
-    return Object.assign(
-      acc,
-      // $FlowFixMe non-literal require
-      require(path.join(root, 'node_modules', pathToPlatform)),
-    );
-  }, {});
+  const projectPlatforms = plugins.platforms.reduce(
+    (acc, pathToPlatform) =>
+      Object.assign(
+        acc,
+        // $FlowFixMe non-literal require
+        require(path.join(root, 'node_modules', pathToPlatform))
+      ),
+    {}
+  );
 
   return {
     ...builtInPlatforms,
     ...projectPlatforms,
   };
-}
+};
diff --git a/packages/local-cli/core/ios/findPodfilePath.js b/packages/local-cli/core/ios/findPodfilePath.js
index 672325354..f2263046b 100644
--- a/packages/local-cli/core/ios/findPodfilePath.js
+++ b/packages/local-cli/core/ios/findPodfilePath.js
@@ -7,8 +7,6 @@
  * @format
  */
 
-'use strict';
-
 const fs = require('fs');
 const path = require('path');
 
diff --git a/packages/local-cli/core/ios/findPodspecName.js b/packages/local-cli/core/ios/findPodspecName.js
index 1041a0a99..cd3d6c7a5 100644
--- a/packages/local-cli/core/ios/findPodspecName.js
+++ b/packages/local-cli/core/ios/findPodspecName.js
@@ -7,24 +7,23 @@
  * @format
  */
 
-'use strict';
-
 const glob = require('glob');
 const path = require('path');
 
 module.exports = function findPodspecName(folder) {
-  const podspecs = glob.sync('*.podspec', {cwd: folder});
+  const podspecs = glob.sync('*.podspec', { cwd: folder });
   let podspecFile = null;
   if (podspecs.length === 0) {
     return null;
-  } else if (podspecs.length === 1) {
-    podspecFile = podspecs[0];
+  }
+  if (podspecs.length === 1) {
+    podspecFile = podspecs[0]; // eslint-disable-line prefer-destructuring
   } else {
     const folderParts = folder.split(path.sep);
     const currentFolder = folderParts[folderParts.length - 1];
-    const toSelect = podspecs.indexOf(currentFolder + '.podspec');
+    const toSelect = podspecs.indexOf(`${currentFolder}.podspec`);
     if (toSelect === -1) {
-      podspecFile = podspecs[0];
+      podspecFile = podspecs[0]; // eslint-disable-line prefer-destructuring
     } else {
       podspecFile = podspecs[toSelect];
     }
diff --git a/packages/local-cli/core/ios/findProject.js b/packages/local-cli/core/ios/findProject.js
index d98695d67..f4ea052a1 100644
--- a/packages/local-cli/core/ios/findProject.js
+++ b/packages/local-cli/core/ios/findProject.js
@@ -7,8 +7,6 @@
  * @format
  */
 
-'use strict';
-
 const glob = require('glob');
 const path = require('path');
 
@@ -46,12 +44,11 @@ module.exports = function findProject(folder) {
       cwd: folder,
       ignore: GLOB_EXCLUDE_PATTERN,
     })
-    .filter(project => {
-      return path.dirname(project) === IOS_BASE || !TEST_PROJECTS.test(project);
-    })
-    .sort((projectA, projectB) => {
-      return path.dirname(projectA) === IOS_BASE ? -1 : 1;
-    });
+    .filter(
+      project =>
+        path.dirname(project) === IOS_BASE || !TEST_PROJECTS.test(project)
+    )
+    .sort(project => (path.dirname(project) === IOS_BASE ? -1 : 1));
 
   if (projects.length === 0) {
     return null;
diff --git a/packages/local-cli/core/ios/index.js b/packages/local-cli/core/ios/index.js
index df8761150..70842f0e0 100644
--- a/packages/local-cli/core/ios/index.js
+++ b/packages/local-cli/core/ios/index.js
@@ -7,25 +7,22 @@
  * @format
  */
 
-'use strict';
-
+const path = require('path');
 const findProject = require('./findProject');
 const findPodfilePath = require('./findPodfilePath');
 const findPodspecName = require('./findPodspecName');
-const path = require('path');
 
 /**
  * For libraries specified without an extension, add '.tbd' for those that
  * start with 'lib' and '.framework' to the rest.
  */
-const mapSharedLibaries = libraries => {
-  return libraries.map(name => {
+const mapSharedLibaries = libraries =>
+  libraries.map(name => {
     if (path.extname(name)) {
       return name;
     }
     return name + (name.indexOf('lib') === 0 ? '.tbd' : '.framework');
   });
-};
 
 /**
  * Returns project config by analyzing given folder and applying some user defaults
@@ -45,11 +42,11 @@ exports.projectConfig = function projectConfigIOS(folder, userConfig) {
 
   return {
     sourceDir: path.dirname(projectPath),
-    folder: folder,
+    folder,
     pbxprojPath: path.join(projectPath, 'project.pbxproj'),
     podfile: findPodfilePath(projectPath),
     podspec: findPodspecName(folder),
-    projectPath: projectPath,
+    projectPath,
     projectName: path.basename(projectPath),
     libraryFolder: userConfig.libraryFolder || 'Libraries',
     sharedLibraries: mapSharedLibaries(userConfig.sharedLibraries || []),
diff --git a/packages/local-cli/core/types.flow.js b/packages/local-cli/core/types.flow.js
index 9434e700c..e06b06f06 100644
--- a/packages/local-cli/core/types.flow.js
+++ b/packages/local-cli/core/types.flow.js
@@ -2,6 +2,8 @@
  * @flow
  */
 
+/* eslint-disable flowtype/no-weak-types */
+
 export type ContextT = {
   root: string,
 };
@@ -10,7 +12,7 @@ export type LocalCommandT = {
   name: string,
   description?: string,
   usage?: string,
-  func: (argv: Array<string>, ctx: ContextT, args: Object) =>?Promise<void>,
+  func: (argv: Array<string>, ctx: ContextT, args: Object) => ?Promise<void>,
   options?: Array<{
     command: string,
     description?: string,
@@ -30,10 +32,10 @@ type Package = {
 
 /**
  * User can define command either as an object (RequiredCommandT) or
- * as an array of commands (Array<RequiredCommandT>). 
+ * as an array of commands (Array<RequiredCommandT>).
  */
 export type ProjectCommandT = LocalCommandT & {
-  pkg: Package
+  pkg: Package,
 };
 
 /**
@@ -48,7 +50,7 @@ export type PlatformConfigT<ProjectConfigT, DependencyConfigT, ParamsT> = {
   projectConfig: (string, ParamsT) => ?ProjectConfigT,
   dependencyConfig: (string, ParamsT) => ?DependencyConfigT,
   /**
-   * @todo(grabbou): This should not be part of the "core". It should be 
+   * @todo(grabbou): This should not be part of the "core". It should be
    * specific to `link` and `unlink`. Remove it from here soon.
    */
   linkConfig: () => {
@@ -57,9 +59,14 @@ export type PlatformConfigT<ProjectConfigT, DependencyConfigT, ParamsT> = {
      */
     isInstalled: (ProjectConfigT, string, DependencyConfigT) => boolean,
     register: (string, DependencyConfigT, Object, ProjectConfigT) => void,
-    unregister: (string, DependencyConfigT, ProjectConfigT, Array<DependencyConfigT>) => void,
+    unregister: (
+      string,
+      DependencyConfigT,
+      ProjectConfigT,
+      Array<DependencyConfigT>
+    ) => void,
     copyAssets: (string[], ProjectConfigT) => void,
-    unlinkAssets: (string[], ProjectConfigT) => void
+    unlinkAssets: (string[], ProjectConfigT) => void,
   },
 };
 
@@ -81,13 +88,13 @@ export type DependencyConfigAndroidT = {};
 
 /**
  * Config of a project.
- * 
+ *
  * When one of the projects is `null`, that means given platform
  * is not available in the current project.
  */
 export type ProjectConfigT = {
   android: ?ProjectConfigAndroidT,
-  ios: ?ProjectConfigIOST
+  ios: ?ProjectConfigIOST,
 };
 
 /**
@@ -96,27 +103,35 @@ export type ProjectConfigT = {
  */
 export type DependencyConfigT = {
   android: ?DependencyConfigAndroidT,
-  ios: ?DependencyConfigIOST
+  ios: ?DependencyConfigIOST,
 };
 
 /**
  * Available platforms. Additional plugins should assert the type on their own.
  */
 export type PlatformsT = {
-  ios: PlatformConfigT<ProjectConfigIOST, DependencyConfigIOST, IOSConfigParamsT>,
-  android: PlatformConfigT<ProjectConfigAndroidT, DependencyConfigAndroidT, AndroidConfigParamsT>,
-  [name: string]: PlatformConfigT<any, any, any>
+  ios: PlatformConfigT<
+    ProjectConfigIOST,
+    DependencyConfigIOST,
+    IOSConfigParamsT
+  >,
+  android: PlatformConfigT<
+    ProjectConfigAndroidT,
+    DependencyConfigAndroidT,
+    AndroidConfigParamsT
+  >,
+  [name: string]: PlatformConfigT<any, any, any>,
 };
 
 export type InquirerPromptT = any;
 
 /**
- * Configuration of the CLI as set by a package in the package.json 
+ * Configuration of the CLI as set by a package in the package.json
  */
 export type PackageConfigurationT = {
   assets?: string[],
   commands?: { [name: string]: string },
   params?: InquirerPromptT[],
   android: AndroidConfigParamsT,
-  ios: IOSConfigParamsT
+  ios: IOSConfigParamsT,
 };
diff --git a/packages/local-cli/dependencies/dependencies.js b/packages/local-cli/dependencies/dependencies.js
index 192926a84..4cc4986d6 100644
--- a/packages/local-cli/dependencies/dependencies.js
+++ b/packages/local-cli/dependencies/dependencies.js
@@ -4,11 +4,9 @@
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
  *
- * @format
+ * @flow
  */
 
-'use strict';
-
 const Metro = require('metro');
 
 const denodeify = require('denodeify');
@@ -20,7 +18,7 @@ async function dependencies(argv, configPromise, args, packagerInstance) {
   const config = await configPromise;
   if (!fs.existsSync(rootModuleAbsolutePath)) {
     return Promise.reject(
-      new Error(`File ${rootModuleAbsolutePath} does not exist`),
+      new Error(`File ${rootModuleAbsolutePath} does not exist`)
     );
   }
 
@@ -28,7 +26,7 @@ async function dependencies(argv, configPromise, args, packagerInstance) {
 
   const relativePath = path.relative(
     config.projectRoot,
-    rootModuleAbsolutePath,
+    rootModuleAbsolutePath
   );
 
   const options = {
@@ -58,7 +56,7 @@ async function dependencies(argv, configPromise, args, packagerInstance) {
       0;
 
     if (isInsideProjectRoots) {
-      outStream.write(modulePath + '\n');
+      outStream.write(`${modulePath}\n`);
     }
   });
   return writeToFile
@@ -99,7 +97,7 @@ module.exports = {
     {
       command: '--dev [boolean]',
       description: 'If false, skip all dev-only code path',
-      parse: val => (val === 'false' ? false : true),
+      parse: val => val !== 'false',
       default: true,
     },
     {
diff --git a/packages/local-cli/eject/eject.js b/packages/local-cli/eject/eject.js
index ff7d085be..5da04b862 100644
--- a/packages/local-cli/eject/eject.js
+++ b/packages/local-cli/eject/eject.js
@@ -7,11 +7,9 @@
  * @format
  */
 
-'use strict';
-
-const copyProjectTemplateAndReplace = require('../generator/copyProjectTemplateAndReplace');
 const path = require('path');
 const fs = require('fs');
+const copyProjectTemplateAndReplace = require('../generator/copyProjectTemplateAndReplace');
 
 /**
  * The eject command re-creates the `android` and `ios` native folders. Because native code can be
@@ -30,7 +28,7 @@ function eject() {
   if (doesIOSExist && doesAndroidExist) {
     console.error(
       'Both the iOS and Android folders already exist! Please delete `ios` and/or `android` ' +
-        'before ejecting.',
+        'before ejecting.'
     );
     process.exit(1);
   }
@@ -42,9 +40,9 @@ function eject() {
     console.error(
       'Eject requires an `app.json` config file to be located at ' +
         `${path.resolve(
-          'app.json',
+          'app.json'
         )}, and it must at least specify a \`name\` for the project ` +
-        "name, and a `displayName` for the app's home screen label.",
+        "name, and a `displayName` for the app's home screen label."
     );
     process.exit(1);
   }
@@ -53,20 +51,22 @@ function eject() {
   if (!appName) {
     console.error(
       'App `name` must be defined in the `app.json` config file to define the project name. ' +
-        'It must not contain any spaces or dashes.',
+        'It must not contain any spaces or dashes.'
     );
     process.exit(1);
   }
+
+  // eslint-disable-next-line prefer-destructuring
   const displayName = appConfig.displayName;
   if (!displayName) {
     console.error(
       'App `displayName` must be defined in the `app.json` config file, to define the label ' +
-        'of the app on the home screen.',
+        'of the app on the home screen.'
     );
     process.exit(1);
   }
 
-  const templateOptions = {displayName};
+  const templateOptions = { displayName };
 
   if (!doesIOSExist) {
     console.log('Generating the iOS folder.');
@@ -77,11 +77,11 @@ function eject() {
         'local-cli',
         'templates',
         'HelloWorld',
-        'ios',
+        'ios'
       ),
       path.resolve('ios'),
       appName,
-      templateOptions,
+      templateOptions
     );
   }
 
@@ -94,11 +94,11 @@ function eject() {
         'local-cli',
         'templates',
         'HelloWorld',
-        'android',
+        'android'
       ),
       path.resolve('android'),
       appName,
-      templateOptions,
+      templateOptions
     );
   }
 }
diff --git a/packages/local-cli/generator/copyProjectTemplateAndReplace.js b/packages/local-cli/generator/copyProjectTemplateAndReplace.js
index 8f04b439f..6b77d7d01 100644
--- a/packages/local-cli/generator/copyProjectTemplateAndReplace.js
+++ b/packages/local-cli/generator/copyProjectTemplateAndReplace.js
@@ -7,11 +7,9 @@
  * @format
  */
 
-'use strict';
-
 const chalk = require('chalk');
-const copyAndReplace = require('../util/copyAndReplace');
 const path = require('path');
+const copyAndReplace = require('../util/copyAndReplace');
 const prompt = require('./promptSync')();
 const walk = require('../util/walk');
 
@@ -33,7 +31,7 @@ function copyProjectTemplateAndReplace(
   srcPath,
   destPath,
   newProjectName,
-  options,
+  options = {}
 ) {
   if (!srcPath) {
     throw new Error('Need a path to copy from');
@@ -45,8 +43,6 @@ function copyProjectTemplateAndReplace(
     throw new Error('Need a project name');
   }
 
-  options = options || {};
-
   walk(srcPath).forEach(absoluteSrcFilePath => {
     // 'react-native upgrade'
     if (options.upgrade) {
@@ -90,13 +86,12 @@ function copyProjectTemplateAndReplace(
 
     let contentChangedCallback = null;
     if (options.upgrade && !options.force) {
-      contentChangedCallback = (_, contentChanged) => {
-        return upgradeFileContentChangedCallback(
+      contentChangedCallback = (_, contentChanged) =>
+        upgradeFileContentChangedCallback(
           absoluteSrcFilePath,
           relativeRenamedPath,
-          contentChanged,
+          contentChanged
         );
-      };
     }
     copyAndReplace(
       absoluteSrcFilePath,
@@ -106,7 +101,7 @@ function copyProjectTemplateAndReplace(
         HelloWorld: newProjectName,
         helloworld: newProjectName.toLowerCase(),
       },
-      contentChangedCallback,
+      contentChangedCallback
     );
   });
 }
@@ -119,11 +114,11 @@ function copyProjectTemplateAndReplace(
  * This is especially important for .gitignore because npm has some special
  * behavior of automatically renaming .gitignore to .npmignore.
  */
-function translateFilePath(path) {
-  if (!path) {
-    return path;
+function translateFilePath(filePath) {
+  if (!filePath) {
+    return filePath;
   }
-  return path
+  return filePath
     .replace('_BUCK', 'BUCK')
     .replace('_gitignore', '.gitignore')
     .replace('_gitattributes', '.gitattributes')
@@ -136,43 +131,36 @@ function translateFilePath(path) {
 function upgradeFileContentChangedCallback(
   absoluteSrcFilePath,
   relativeDestPath,
-  contentChanged,
+  contentChanged
 ) {
   if (contentChanged === 'new') {
-    console.log(chalk.bold('new') + ' ' + relativeDestPath);
+    console.log(`${chalk.bold('new')} ${relativeDestPath}`);
     return 'overwrite';
-  } else if (contentChanged === 'changed') {
+  }
+  if (contentChanged === 'changed') {
     console.log(
-      chalk.bold(relativeDestPath) +
-        ' ' +
-        'has changed in the new version.\nDo you want to keep your ' +
-        relativeDestPath +
-        ' or replace it with the ' +
-        'latest version?\nIf you ever made any changes ' +
-        "to this file, you'll probably want to keep it.\n" +
-        'You can see the new version here: ' +
-        absoluteSrcFilePath +
-        '\n' +
-        'Do you want to replace ' +
-        relativeDestPath +
-        '? ' +
-        'Answer y to replace, n to keep your version: ',
+      `${chalk.bold(relativeDestPath)} ` +
+        `has changed in the new version.\nDo you want to keep your ${relativeDestPath} or replace it with the ` +
+        `latest version?\nIf you ever made any changes ` +
+        `to this file, you'll probably want to keep it.\n` +
+        `You can see the new version here: ${absoluteSrcFilePath}\n` +
+        `Do you want to replace ${relativeDestPath}? ` +
+        `Answer y to replace, n to keep your version: `
     );
     const answer = prompt();
     if (answer === 'y') {
-      console.log('Replacing ' + relativeDestPath);
+      console.log(`Replacing ${relativeDestPath}`);
       return 'overwrite';
-    } else {
-      console.log('Keeping your ' + relativeDestPath);
-      return 'keep';
     }
-  } else if (contentChanged === 'identical') {
+    console.log(`Keeping your ${relativeDestPath}`);
+    return 'keep';
+  }
+  if (contentChanged === 'identical') {
     return 'keep';
-  } else {
-    throw new Error(
-      `Unknown file changed state: ${relativeDestPath}, ${contentChanged}`,
-    );
   }
+  throw new Error(
+    `Unknown file changed state: ${relativeDestPath}, ${contentChanged}`
+  );
 }
 
 module.exports = copyProjectTemplateAndReplace;
diff --git a/packages/local-cli/generator/printRunInstructions.js b/packages/local-cli/generator/printRunInstructions.js
index 7110f646a..b011902ab 100644
--- a/packages/local-cli/generator/printRunInstructions.js
+++ b/packages/local-cli/generator/printRunInstructions.js
@@ -7,31 +7,32 @@
  * @format
  */
 
-'use strict';
-
-var chalk = require('chalk');
-var path = require('path');
+const chalk = require('chalk');
+const path = require('path');
 
 function printRunInstructions(projectDir, projectName) {
   const absoluteProjectDir = path.resolve(projectDir);
   // iOS
-  const xcodeProjectPath =
-    path.resolve(projectDir, 'ios', projectName) + '.xcodeproj';
+  const xcodeProjectPath = `${path.resolve(
+    projectDir,
+    'ios',
+    projectName
+  )}.xcodeproj`;
   const relativeXcodeProjectPath = path.relative(
     process.cwd(),
-    xcodeProjectPath,
+    xcodeProjectPath
   );
   console.log(chalk.white.bold('To run your app on iOS:'));
-  console.log('   cd ' + absoluteProjectDir);
+  console.log(`   cd ${absoluteProjectDir}`);
   console.log('   react-native run-ios');
   console.log('   - or -');
-  console.log('   Open ' + relativeXcodeProjectPath + ' in Xcode');
+  console.log(`   Open ${relativeXcodeProjectPath} in Xcode`);
   console.log('   Hit the Run button');
   // Android
   console.log(chalk.white.bold('To run your app on Android:'));
-  console.log('   cd ' + absoluteProjectDir);
+  console.log(`   cd ${absoluteProjectDir}`);
   console.log(
-    '   Have an Android emulator running (quickest way to get started), or a device connected',
+    '   Have an Android emulator running (quickest way to get started), or a device connected'
   );
   console.log('   react-native run-android');
 }
diff --git a/packages/local-cli/generator/promptSync.js b/packages/local-cli/generator/promptSync.js
index 2388ef046..41a874f23 100644
--- a/packages/local-cli/generator/promptSync.js
+++ b/packages/local-cli/generator/promptSync.js
@@ -10,16 +10,17 @@
 // Simplified version of:
 // https://github.com/0x00A/prompt-sync/blob/master/index.js
 
-'use strict';
+/* eslint-disable */
 
-var fs = require('fs');
-var term = 13; // carriage return
+const fs = require('fs');
+
+const term = 13; // carriage return
 
 function create() {
   return prompt;
 
   function prompt(ask, value, opts) {
-    var insert = 0;
+    let insert = 0;
     opts = opts || {};
 
     if (Object(ask) === ask) {
@@ -30,23 +31,25 @@ function create() {
       value = opts.value;
     }
     ask = ask || '';
-    var echo = opts.echo;
-    var masked = 'echo' in opts;
+    const echo = opts.echo;
+    const masked = 'echo' in opts;
 
-    var fd =
+    const fd =
       process.platform === 'win32'
         ? process.stdin.fd
         : fs.openSync('/dev/tty', 'rs');
 
-    var wasRaw = process.stdin.isRaw;
+    const wasRaw = process.stdin.isRaw;
     if (!wasRaw) {
       process.stdin.setRawMode(true);
     }
 
-    var buf = Buffer.alloc(3);
-    var str = '',
-      character,
-      read;
+    let buf = Buffer.alloc(3);
+    let str = '';
+
+    let character;
+
+    let read;
 
     if (ask) {
       process.stdout.write(ask);
@@ -57,11 +60,11 @@ function create() {
       if (read > 1) {
         // received a control sequence
         if (buf.toString()) {
-          str = str + buf.toString();
+          str += buf.toString();
           str = str.replace(/\0/g, '');
           insert = str.length;
-          process.stdout.write('\u001b[2K\u001b[0G' + ask + str);
-          process.stdout.write('\u001b[' + (insert + ask.length + 1) + 'G');
+          process.stdout.write(`\u001b[2K\u001b[0G${ask}${str}`);
+          process.stdout.write(`\u001b[${insert + ask.length + 1}G`);
           buf = Buffer.alloc(3);
         }
         continue; // any other 3 character sequence is ignored
@@ -89,7 +92,7 @@ function create() {
         character === 127 ||
         (process.platform === 'win32' && character === 8)
       ) {
-        //backspace
+        // backspace
         if (!insert) {
           continue;
         }
@@ -109,24 +112,18 @@ function create() {
 
       if (masked) {
         process.stdout.write(
-          '\u001b[2K\u001b[0G' + ask + Array(str.length + 1).join(echo),
+          `\u001b[2K\u001b[0G${ask}${Array(str.length + 1).join(echo)}`
         );
       } else {
         process.stdout.write('\u001b[s');
         if (insert === str.length) {
-          process.stdout.write('\u001b[2K\u001b[0G' + ask + str);
+          process.stdout.write(`\u001b[2K\u001b[0G${ask}${str}`);
+        } else if (ask) {
+          process.stdout.write(`\u001b[2K\u001b[0G${ask}${str}`);
         } else {
-          if (ask) {
-            process.stdout.write('\u001b[2K\u001b[0G' + ask + str);
-          } else {
-            process.stdout.write(
-              '\u001b[2K\u001b[0G' +
-                str +
-                '\u001b[' +
-                (str.length - insert) +
-                'D',
-            );
-          }
+          process.stdout.write(
+            `\u001b[2K\u001b[0G${str}\u001b[${str.length - insert}D`
+          );
         }
         process.stdout.write('\u001b[u');
         process.stdout.write('\u001b[1C');
diff --git a/packages/local-cli/generator/templates.js b/packages/local-cli/generator/templates.js
index 544940a7d..5d262be11 100644
--- a/packages/local-cli/generator/templates.js
+++ b/packages/local-cli/generator/templates.js
@@ -7,12 +7,10 @@
  * @format
  */
 
-'use strict';
-
-const copyProjectTemplateAndReplace = require('./copyProjectTemplateAndReplace');
-const execSync = require('child_process').execSync;
+const { execSync } = require('child_process');
 const fs = require('fs');
 const path = require('path');
+const copyProjectTemplateAndReplace = require('./copyProjectTemplateAndReplace');
 
 /**
  * @param destPath Create the new project at this path.
@@ -25,13 +23,13 @@ function createProjectFromTemplate(
   destPath,
   newProjectName,
   template,
-  yarnVersion,
+  yarnVersion
 ) {
   // Expand the basic 'HelloWorld' template
   copyProjectTemplateAndReplace(
     path.resolve(__dirname, '../templates/HelloWorld'),
     destPath,
-    newProjectName,
+    newProjectName
   );
 
   if (template === undefined) {
@@ -59,7 +57,7 @@ function createFromRemoteTemplate(
   template,
   destPath,
   newProjectName,
-  yarnVersion,
+  yarnVersion
 ) {
   let installPackage;
   let templateName;
@@ -69,7 +67,7 @@ function createFromRemoteTemplate(
     templateName = template.substr(template.lastIndexOf('/') + 1);
   } else {
     // e.g 'demo'
-    installPackage = 'react-native-template-' + template;
+    installPackage = `react-native-template-${template}`;
     templateName = installPackage;
   }
 
@@ -83,7 +81,7 @@ function createFromRemoteTemplate(
     } else {
       execSync(
         `npm install ${installPackage} --save --save-exact --ignore-scripts`,
-        {stdio: 'inherit'},
+        { stdio: 'inherit' }
       );
     }
     const templatePath = path.resolve('node_modules', templateName);
@@ -113,7 +111,7 @@ function createFromRemoteTemplate(
       // if this the clean up fails.
       console.warn(
         `Failed to clean up template temp files in node_modules/${templateName}. ` +
-          'This is not a critical error, you can work on your app.',
+          'This is not a critical error, you can work on your app.'
       );
     }
   }
@@ -134,15 +132,15 @@ function installTemplateDependencies(templatePath, yarnVersion) {
     dependencies = JSON.parse(fs.readFileSync(dependenciesJsonPath));
   } catch (err) {
     throw new Error(
-      "Could not parse the template's dependencies.json: " + err.message,
+      `Could not parse the template's dependencies.json: ${err.message}`
     );
   }
-  for (let depName in dependencies) {
+  for (const depName of Object.keys(dependencies)) {
     const depVersion = dependencies[depName];
-    const depToInstall = depName + '@' + depVersion;
-    console.log('Adding ' + depToInstall + '...');
+    const depToInstall = `${depName}@${depVersion}`;
+    console.log(`Adding ${depToInstall}...`);
     if (yarnVersion) {
-      execSync(`yarn add ${depToInstall}`, {stdio: 'inherit'});
+      execSync(`yarn add ${depToInstall}`, { stdio: 'inherit' });
     } else {
       execSync(`npm install ${depToInstall} --save --save-exact`, {
         stdio: 'inherit',
@@ -150,7 +148,7 @@ function installTemplateDependencies(templatePath, yarnVersion) {
     }
   }
   console.log("Linking native dependencies into the project's build files...");
-  execSync('react-native link', {stdio: 'inherit'});
+  execSync('react-native link', { stdio: 'inherit' });
 }
 
 function installTemplateDevDependencies(templatePath, yarnVersion) {
@@ -158,7 +156,7 @@ function installTemplateDevDependencies(templatePath, yarnVersion) {
   // that are required by this template
   const devDependenciesJsonPath = path.resolve(
     templatePath,
-    'devDependencies.json',
+    'devDependencies.json'
   );
   console.log('Adding develop dependencies for the project...');
   if (!fs.existsSync(devDependenciesJsonPath)) {
@@ -171,15 +169,15 @@ function installTemplateDevDependencies(templatePath, yarnVersion) {
     dependencies = JSON.parse(fs.readFileSync(devDependenciesJsonPath));
   } catch (err) {
     throw new Error(
-      "Could not parse the template's devDependencies.json: " + err.message,
+      `Could not parse the template's devDependencies.json: ${err.message}`
     );
   }
-  for (let depName in dependencies) {
+  for (const depName of Object.keys(dependencies)) {
     const depVersion = dependencies[depName];
-    const depToInstall = depName + '@' + depVersion;
-    console.log('Adding ' + depToInstall + '...');
+    const depToInstall = `${depName}@${depVersion}`;
+    console.log(`Adding ${depToInstall}...`);
     if (yarnVersion) {
-      execSync(`yarn add ${depToInstall} -D`, {stdio: 'inherit'});
+      execSync(`yarn add ${depToInstall} -D`, { stdio: 'inherit' });
     } else {
       execSync(`npm install ${depToInstall} --save-dev --save-exact`, {
         stdio: 'inherit',
diff --git a/packages/local-cli/info/info.js b/packages/local-cli/info/info.js
index 9f09de587..4dbe517ce 100644
--- a/packages/local-cli/info/info.js
+++ b/packages/local-cli/info/info.js
@@ -7,13 +7,9 @@
  * @format
  */
 
-'use strict';
-
 const envinfo = require('envinfo');
 
-const info = function() {
-  const args = Array.prototype.slice.call(arguments)[2];
-
+const info = function getInfo(argv, ctx, options) {
   try {
     envinfo
       .run(
@@ -23,19 +19,19 @@ const info = function() {
           IDEs: ['Xcode', 'Android Studio'],
           SDKs: ['iOS SDK', 'Android SDK'],
           npmPackages:
-            (typeof args.packages === 'string' &&
-              !args.packages.includes('*')) ||
-            !args.packages
+            (typeof options.packages === 'string' &&
+              !options.packages.includes('*')) ||
+            !options.packages
               ? ['react', 'react-native'].concat(
-                  (args.packages || '').split(','),
+                  (options.packages || '').split(',')
                 )
-              : args.packages,
+              : options.packages,
           npmGlobalPackages: '*react-native*',
         },
         {
-          clipboard: !!args.clipboard,
+          clipboard: !!options.clipboard,
           title: 'React Native Environment Info',
-        },
+        }
       )
       .then(console.log)
       .catch(err => {
diff --git a/packages/local-cli/init/init.js b/packages/local-cli/init/init.js
index fc0f81d71..96bfb0ba6 100644
--- a/packages/local-cli/init/init.js
+++ b/packages/local-cli/init/init.js
@@ -7,15 +7,13 @@
  * @format
  */
 
-'use strict';
-
-const {createProjectFromTemplate} = require('../generator/templates');
-const execSync = require('child_process').execSync;
+const { execSync } = require('child_process');
 const fs = require('fs');
 const minimist = require('minimist');
 const path = require('path');
-const printRunInstructions = require('../generator/printRunInstructions');
 const process = require('process');
+const printRunInstructions = require('../generator/printRunInstructions');
+const { createProjectFromTemplate } = require('../generator/templates');
 const yarn = require('../util/yarn');
 
 /**
@@ -41,7 +39,7 @@ function init(projectDir, argsOrName) {
   const newProjectName = args[0];
   const options = minimist(args);
 
-  console.log('Setting up new React Native app in ' + projectDir);
+  console.log(`Setting up new React Native app in ${projectDir}`);
   generateProject(projectDir, newProjectName, options);
 }
 
@@ -51,19 +49,19 @@ function init(projectDir, argsOrName) {
  * @param options Command line arguments parsed by minimist.
  */
 function generateProject(destinationRoot, newProjectName, options) {
-  var reactNativePackageJson = require.resolve('react-native/package.json');
-  var {peerDependencies} = reactNativePackageJson;
+  const reactNativePackageJson = require.resolve('react-native/package.json');
+  const { peerDependencies } = reactNativePackageJson;
   if (!peerDependencies) {
     console.error(
-      "Missing React peer dependency in React Native's package.json. Aborting.",
+      "Missing React peer dependency in React Native's package.json. Aborting."
     );
     return;
   }
 
-  var reactVersion = peerDependencies.react;
+  const reactVersion = peerDependencies.react;
   if (!reactVersion) {
     console.error(
-      "Missing React peer dependency in React Native's package.json. Aborting.",
+      "Missing React peer dependency in React Native's package.json. Aborting."
     );
     return;
   }
@@ -77,12 +75,12 @@ function generateProject(destinationRoot, newProjectName, options) {
     destinationRoot,
     newProjectName,
     options.template,
-    yarnVersion,
+    yarnVersion
   );
 
   if (yarnVersion) {
     console.log('Adding React...');
-    execSync(`yarn add react@${reactVersion}`, {stdio: 'inherit'});
+    execSync(`yarn add react@${reactVersion}`, { stdio: 'inherit' });
   } else {
     console.log('Installing React...');
     execSync(`npm install react@${reactVersion} --save --save-exact`, {
@@ -93,7 +91,7 @@ function generateProject(destinationRoot, newProjectName, options) {
     const jestDeps = `jest babel-jest metro-react-native-babel-preset react-test-renderer@${reactVersion}`;
     if (yarnVersion) {
       console.log('Adding Jest...');
-      execSync(`yarn add ${jestDeps} --dev --exact`, {stdio: 'inherit'});
+      execSync(`yarn add ${jestDeps} --dev --exact`, { stdio: 'inherit' });
     } else {
       console.log('Installing Jest...');
       execSync(`npm install ${jestDeps} --save-dev --save-exact`, {
@@ -109,8 +107,8 @@ function generateProject(destinationRoot, newProjectName, options) {
  * Add Jest-related stuff to package.json, which was created by the react-native-cli.
  */
 function addJestToPackageJson(destinationRoot) {
-  var packageJSONPath = path.join(destinationRoot, 'package.json');
-  var packageJSON = JSON.parse(fs.readFileSync(packageJSONPath));
+  const packageJSONPath = path.join(destinationRoot, 'package.json');
+  const packageJSON = JSON.parse(fs.readFileSync(packageJSONPath));
 
   packageJSON.scripts.test = 'jest';
   packageJSON.jest = {
diff --git a/packages/local-cli/install/install.js b/packages/local-cli/install/install.js
index b15a3e6d5..25a2ba776 100644
--- a/packages/local-cli/install/install.js
+++ b/packages/local-cli/install/install.js
@@ -7,11 +7,10 @@
  * @format
  */
 
-'use strict';
-
-const spawnSync = require('child_process').spawnSync;
+const { spawnSync } = require('child_process');
 const log = require('npmlog');
 const PackageManager = require('../util/PackageManager');
+
 const spawnOpts = {
   stdio: 'inherit',
   stdin: 'inherit',
@@ -19,7 +18,7 @@ const spawnOpts = {
 
 log.heading = 'rnpm-install';
 
-function install(args, config) {
+function install(args) {
   const name = args[0];
 
   let res = PackageManager.add(name);
diff --git a/packages/local-cli/install/uninstall.js b/packages/local-cli/install/uninstall.js
index 096396220..af056073b 100644
--- a/packages/local-cli/install/uninstall.js
+++ b/packages/local-cli/install/uninstall.js
@@ -7,11 +7,10 @@
  * @format
  */
 
-'use strict';
-
-const spawnSync = require('child_process').spawnSync;
+const { spawnSync } = require('child_process');
 const log = require('npmlog');
 const PackageManager = require('../util/PackageManager');
+
 const spawnOpts = {
   stdio: 'inherit',
   stdin: 'inherit',
@@ -19,10 +18,10 @@ const spawnOpts = {
 
 log.heading = 'rnpm-install';
 
-function uninstall(args, config) {
+function uninstall(args) {
   const name = args[0];
 
-  var res = spawnSync('react-native', ['unlink', name], spawnOpts);
+  let res = spawnSync('react-native', ['unlink', name], spawnOpts);
 
   if (res.status) {
     process.exit(res.status);
diff --git a/packages/local-cli/library/library.js b/packages/local-cli/library/library.js
index 23a82a1ee..d4a1dea04 100644
--- a/packages/local-cli/library/library.js
+++ b/packages/local-cli/library/library.js
@@ -7,23 +7,20 @@
  * @format
  */
 
-'use strict';
-
-const copyAndReplace = require('../util/copyAndReplace');
 const fs = require('fs');
-const isValidPackageName = require('../util/isValidPackageName');
 const path = require('path');
+const copyAndReplace = require('../util/copyAndReplace');
+const isValidPackageName = require('../util/isValidPackageName');
 const walk = require('../util/walk');
 
 /**
  * Creates a new native library with the given name
  */
-function library(argv, config, args) {
+async function library(argv, config, args) {
   if (!isValidPackageName(args.name)) {
-    return Promise.reject(
-      args.name +
-        ' is not a valid name for a project. Please use a valid ' +
-        'identifier name (alphanumeric).',
+    throw new Error(
+      `${args.name} is not a valid name for a project. Please use a valid ` +
+        `identifier name (alphanumeric).`
     );
   }
 
@@ -34,7 +31,7 @@ function library(argv, config, args) {
     'node_modules',
     'react-native',
     'Libraries',
-    'Sample',
+    'Sample'
   );
 
   if (!fs.existsSync(libraries)) {
@@ -42,9 +39,7 @@ function library(argv, config, args) {
   }
 
   if (fs.existsSync(libraryDest)) {
-    return Promise.reject(
-      new Error(`Library already exists in ${libraryDest}`),
-    );
+    throw new Error(`Library already exists in ${libraryDest}`);
   }
 
   walk(source).forEach(f => {
@@ -57,7 +52,7 @@ function library(argv, config, args) {
 
     const dest = path.relative(
       source,
-      f.replace(/Sample/g, args.name).replace(/^_/, '.'),
+      f.replace(/Sample/g, args.name).replace(/^_/, '.')
     );
     copyAndReplace(path.resolve(source, f), path.resolve(libraryDest, dest), {
       Sample: args.name,
@@ -69,7 +64,7 @@ function library(argv, config, args) {
   console.log('   Link your library in Xcode:');
   console.log(
     '   https://facebook.github.io/react-native/docs/' +
-      'linking-libraries-ios.html#content\n',
+      'linking-libraries-ios.html#content\n'
   );
 }
 
diff --git a/packages/local-cli/link/__tests__/android/applyPatch-test.js b/packages/local-cli/link/__tests__/android/applyPatch-test.js
index aea686d08..93de418a0 100644
--- a/packages/local-cli/link/__tests__/android/applyPatch-test.js
+++ b/packages/local-cli/link/__tests__/android/applyPatch-test.js
@@ -3,19 +3,16 @@
  *
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
- *
- * @format
- * @emails oncall+javascript_foundation
  */
 
-'use strict';
+/* eslint-disable no-template-curly-in-string */
 
 const applyParams = require('../../android/patches/applyParams');
 
 describe('applyParams', () => {
   it('apply params to the string', () => {
-    expect(applyParams('${foo}', {foo: 'foo'}, 'react-native')).toEqual(
-      'getResources().getString(R.string.reactNative_foo)',
+    expect(applyParams('${foo}', { foo: 'foo' }, 'react-native')).toEqual(
+      'getResources().getString(R.string.reactNative_foo)'
     );
   });
 
diff --git a/packages/local-cli/link/__tests__/android/isInstalled-test.js b/packages/local-cli/link/__tests__/android/isInstalled-test.js
index 28bc43f11..bf7f3bc52 100644
--- a/packages/local-cli/link/__tests__/android/isInstalled-test.js
+++ b/packages/local-cli/link/__tests__/android/isInstalled-test.js
@@ -8,15 +8,13 @@
  * @emails oncall+javascript_foundation
  */
 
-'use strict';
-
 const path = require('path');
 const isInstalled = require('../../android/isInstalled');
 
 const projectConfig = {
   buildGradlePath: path.join(
     __dirname,
-    '../../__fixtures__/android/patchedBuild.gradle',
+    '../../__fixtures__/android/patchedBuild.gradle'
   ),
 };
 
diff --git a/packages/local-cli/link/__tests__/android/makeBuildPatch-test.js b/packages/local-cli/link/__tests__/android/makeBuildPatch-test.js
index e630f7664..a5c1a67e4 100644
--- a/packages/local-cli/link/__tests__/android/makeBuildPatch-test.js
+++ b/packages/local-cli/link/__tests__/android/makeBuildPatch-test.js
@@ -8,8 +8,6 @@
  * @emails oncall+javascript_foundation
  */
 
-'use strict';
-
 const makeBuildPatch = require('../../android/patches/makeBuildPatch');
 const normalizeProjectName = require('../../android/patches/normalizeProjectName');
 
@@ -20,17 +18,17 @@ const normalizedScopedName = normalizeProjectName('@scoped/test');
 describe('makeBuildPatch', () => {
   it('should build a patch function', () => {
     expect(Object.prototype.toString(makeBuildPatch(name))).toBe(
-      '[object Object]',
+      '[object Object]'
     );
   });
 
   it('should make a correct patch', () => {
-    const {patch} = makeBuildPatch(name);
+    const { patch } = makeBuildPatch(name);
     expect(patch).toBe(`    implementation project(':${name}')\n`);
   });
 
   it('should make a correct install check pattern', () => {
-    const {installPattern} = makeBuildPatch(name);
+    const { installPattern } = makeBuildPatch(name);
     const match = `/\\s{4}(implementation)(\\(|\\s)(project)\\(\\':${name}\\'\\)(\\)|\\s)/`;
     expect(installPattern.toString()).toBe(match);
   });
@@ -38,14 +36,14 @@ describe('makeBuildPatch', () => {
 
 describe('makeBuildPatchWithScopedPackage', () => {
   it('should make a correct patch', () => {
-    const {patch} = makeBuildPatch(scopedName);
+    const { patch } = makeBuildPatch(scopedName);
     expect(patch).toBe(
-      `    implementation project(':${normalizedScopedName}')\n`,
+      `    implementation project(':${normalizedScopedName}')\n`
     );
   });
 
   it('should make a correct install check pattern', () => {
-    const {installPattern} = makeBuildPatch(scopedName);
+    const { installPattern } = makeBuildPatch(scopedName);
     const match = `/\\s{4}(implementation)(\\(|\\s)(project)\\(\\':${normalizedScopedName}\\'\\)(\\)|\\s)/`;
     expect(installPattern.toString()).toBe(match);
   });
diff --git a/packages/local-cli/link/__tests__/android/makeImportPatch-test.js b/packages/local-cli/link/__tests__/android/makeImportPatch-test.js
index 8a5d32358..8fcb305c0 100644
--- a/packages/local-cli/link/__tests__/android/makeImportPatch-test.js
+++ b/packages/local-cli/link/__tests__/android/makeImportPatch-test.js
@@ -8,8 +8,6 @@
  * @emails oncall+javascript_foundation
  */
 
-'use strict';
-
 const makeImportPatch = require('../../android/patches/makeImportPatch');
 
 const packageImportPath = 'import some.example.project';
@@ -17,13 +15,13 @@ const packageImportPath = 'import some.example.project';
 describe('makeImportPatch', () => {
   it('should build a patch', () => {
     expect(Object.prototype.toString(makeImportPatch(packageImportPath))).toBe(
-      '[object Object]',
+      '[object Object]'
     );
   });
 
   it('MainActivity contains a correct import patch', () => {
-    const {patch} = makeImportPatch(packageImportPath);
+    const { patch } = makeImportPatch(packageImportPath);
 
-    expect(patch).toBe('\n' + packageImportPath);
+    expect(patch).toBe(`\n${packageImportPath}`);
   });
 });
diff --git a/packages/local-cli/link/__tests__/android/makePackagePatch-test.js b/packages/local-cli/link/__tests__/android/makePackagePatch-test.js
index 6dada4508..23a4eba1e 100644
--- a/packages/local-cli/link/__tests__/android/makePackagePatch-test.js
+++ b/packages/local-cli/link/__tests__/android/makePackagePatch-test.js
@@ -3,12 +3,9 @@
  *
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
- *
- * @format
- * @emails oncall+javascript_foundation
  */
 
-'use strict';
+/* eslint-disable no-template-curly-in-string */
 
 const makePackagePatch = require('../../android/patches/makePackagePatch');
 const applyParams = require('../../android/patches/applyParams');
@@ -27,9 +24,9 @@ describe('makePackagePatch@0.20', () => {
   });
 
   it('MainActivity contains a correct 0.20 import patch', () => {
-    const {patch} = makePackagePatch(packageInstance, params, name);
+    const { patch } = makePackagePatch(packageInstance, params, name);
     const processedInstance = applyParams(packageInstance, params, name);
 
-    expect(patch).toBe(',\n            ' + processedInstance);
+    expect(patch).toBe(`,\n            ${processedInstance}`);
   });
 });
diff --git a/packages/local-cli/link/__tests__/android/makeSettingsPatch-test.js b/packages/local-cli/link/__tests__/android/makeSettingsPatch-test.js
index 6df7b0dd9..e16adbbaf 100644
--- a/packages/local-cli/link/__tests__/android/makeSettingsPatch-test.js
+++ b/packages/local-cli/link/__tests__/android/makeSettingsPatch-test.js
@@ -8,8 +8,6 @@
  * @emails oncall+javascript_foundation
  */
 
-'use strict';
-
 const path = require('path');
 const makeSettingsPatch = require('../../android/patches/makeSettingsPatch');
 const normalizeProjectName = require('../../android/patches/normalizeProjectName');
@@ -32,23 +30,23 @@ describe('makeSettingsPatch', () => {
   it('should build a patch function', () => {
     expect(
       Object.prototype.toString(
-        makeSettingsPatch(name, dependencyConfig, projectConfig),
-      ),
+        makeSettingsPatch(name, dependencyConfig, projectConfig)
+      )
     ).toBe('[object Object]');
   });
 
   it('should make a correct patch', () => {
     const projectDir = path.relative(
       path.dirname(projectConfig.settingsGradlePath),
-      dependencyConfig.sourceDir,
+      dependencyConfig.sourceDir
     );
 
-    const {patch} = makeSettingsPatch(name, dependencyConfig, projectConfig);
+    const { patch } = makeSettingsPatch(name, dependencyConfig, projectConfig);
 
     expect(patch).toBe(
       `include ':${name}'\n` +
         `project(':${name}').projectDir = ` +
-        `new File(rootProject.projectDir, '${projectDir}')\n`,
+        `new File(rootProject.projectDir, '${projectDir}')\n`
     );
   });
 });
@@ -57,27 +55,27 @@ describe('makeSettingsPatchWithScopedPackage', () => {
   it('should build a patch function', () => {
     expect(
       Object.prototype.toString(
-        makeSettingsPatch(scopedName, scopedDependencyConfig, projectConfig),
-      ),
+        makeSettingsPatch(scopedName, scopedDependencyConfig, projectConfig)
+      )
     ).toBe('[object Object]');
   });
 
   it('should make a correct patch', () => {
     const projectDir = path.relative(
       path.dirname(projectConfig.settingsGradlePath),
-      scopedDependencyConfig.sourceDir,
+      scopedDependencyConfig.sourceDir
     );
 
-    const {patch} = makeSettingsPatch(
+    const { patch } = makeSettingsPatch(
       scopedName,
       scopedDependencyConfig,
-      projectConfig,
+      projectConfig
     );
 
     expect(patch).toBe(
       `include ':${normalizedScopedName}'\n` +
         `project(':${normalizedScopedName}').projectDir = ` +
-        `new File(rootProject.projectDir, '${projectDir}')\n`,
+        `new File(rootProject.projectDir, '${projectDir}')\n`
     );
   });
 });
diff --git a/packages/local-cli/link/__tests__/android/makeStringsPatch-test.js b/packages/local-cli/link/__tests__/android/makeStringsPatch-test.js
index 4ea281640..1d7b2553e 100644
--- a/packages/local-cli/link/__tests__/android/makeStringsPatch-test.js
+++ b/packages/local-cli/link/__tests__/android/makeStringsPatch-test.js
@@ -8,8 +8,6 @@
  * @emails oncall+javascript_foundation
  */
 
-'use strict';
-
 const makeStringsPatch = require('../../android/patches/makeStringsPatch');
 
 describe('makeStringsPatch', () => {
@@ -19,7 +17,7 @@ describe('makeStringsPatch', () => {
     };
 
     expect(makeStringsPatch(params, 'module').patch).toContain(
-      '<string moduleConfig="true" name="module_keyA">valueA</string>',
+      '<string moduleConfig="true" name="module_keyA">valueA</string>'
     );
   });
 
diff --git a/packages/local-cli/link/__tests__/android/normalizeProjectName-test.js b/packages/local-cli/link/__tests__/android/normalizeProjectName-test.js
index 93f425fd2..6d8c9c8b9 100644
--- a/packages/local-cli/link/__tests__/android/normalizeProjectName-test.js
+++ b/packages/local-cli/link/__tests__/android/normalizeProjectName-test.js
@@ -8,8 +8,6 @@
  * @emails oncall+javascript_foundation
  */
 
-'use strict';
-
 const normalizeProjectName = require('../../android/patches/normalizeProjectName');
 
 const name = 'test';
diff --git a/packages/local-cli/link/__tests__/getDependencyConfig-test.js b/packages/local-cli/link/__tests__/getDependencyConfig-test.js
index 78a4bfdbe..267da1254 100644
--- a/packages/local-cli/link/__tests__/getDependencyConfig-test.js
+++ b/packages/local-cli/link/__tests__/getDependencyConfig-test.js
@@ -8,8 +8,6 @@
  * @emails oncall+javascript_foundation
  */
 
-'use strict';
-
 const platforms = {
   ios: {
     dependencyConfig: () => ({ sampleiOSKey: '' }),
@@ -19,7 +17,7 @@ const platforms = {
   },
 };
 
-jest.setMock('../../core/getPackageConfiguration', (folder) => {
+jest.setMock('../../core/getPackageConfiguration', folder => {
   if (folder === '/root/node_modules/abcd') {
     throw new Error('Cannot require');
   }
@@ -30,17 +28,18 @@ const getDependencyConfig = require('../getDependencyConfig');
 
 describe('getDependencyConfig', () => {
   it("should return an array of dependencies' config", () => {
-    const dependencies = getDependencyConfig({ root: '/root' }, platforms, ['react-native-windows']);
+    const dependencies = getDependencyConfig({ root: '/root' }, platforms, [
+      'react-native-windows',
+    ]);
 
     expect(dependencies).toMatchSnapshot();
   });
 
   it('should filter out invalid react-native projects', () => {
-    const dependencies = getDependencyConfig(
-      { root: '/root' },
-      platforms,
-      ['react-native-windows', 'abcd']
-    );
+    const dependencies = getDependencyConfig({ root: '/root' }, platforms, [
+      'react-native-windows',
+      'abcd',
+    ]);
 
     expect(dependencies).toMatchSnapshot();
   });
diff --git a/packages/local-cli/link/__tests__/getProjectDependencies-test.js b/packages/local-cli/link/__tests__/getProjectDependencies-test.js
index 82a5e0109..268a48436 100644
--- a/packages/local-cli/link/__tests__/getProjectDependencies-test.js
+++ b/packages/local-cli/link/__tests__/getProjectDependencies-test.js
@@ -9,10 +9,8 @@
  * @format
  */
 
-'use strict';
-
-const getProjectDependencies = require('../getProjectDependencies');
 const path = require('path');
+const getProjectDependencies = require('../getProjectDependencies');
 
 const CWD = path.resolve(__dirname, '../../');
 
@@ -22,7 +20,11 @@ describe('getProjectDependencies', () => {
   });
   it('should return an array of project dependencies', () => {
     jest.setMock(path.join(CWD, './package.json'), {
-      dependencies: {lodash: '^6.0.0', 'react-native': '^16.0.0', 'react-native-local-cli': '*'},
+      dependencies: {
+        lodash: '^6.0.0',
+        'react-native': '^16.0.0',
+        'react-native-local-cli': '*',
+      },
     });
 
     expect(getProjectDependencies(CWD)).toEqual(['lodash']);
diff --git a/packages/local-cli/link/__tests__/groupFilesByType-test.js b/packages/local-cli/link/__tests__/groupFilesByType-test.js
index 173857927..1d86a1cbb 100644
--- a/packages/local-cli/link/__tests__/groupFilesByType-test.js
+++ b/packages/local-cli/link/__tests__/groupFilesByType-test.js
@@ -8,8 +8,6 @@
  * @emails oncall+javascript_foundation
  */
 
-'use strict';
-
 const groupFilesByType = require('../groupFilesByType');
 
 describe('groupFilesByType', () => {
diff --git a/packages/local-cli/link/__tests__/ios/addFileToProject-test.js b/packages/local-cli/link/__tests__/ios/addFileToProject-test.js
index 397b25019..ad3eefbb6 100644
--- a/packages/local-cli/link/__tests__/ios/addFileToProject-test.js
+++ b/packages/local-cli/link/__tests__/ios/addFileToProject-test.js
@@ -8,15 +8,13 @@
  * @emails oncall+javascript_foundation
  */
 
-'use strict';
-
 const xcode = require('xcode');
 const path = require('path');
-const addFileToProject = require('../../ios/addFileToProject');
 const _ = require('lodash');
+const addFileToProject = require('../../ios/addFileToProject');
 
 const project = xcode.project(
-  path.join(__dirname, '../../__fixtures__/project.pbxproj'),
+  path.join(__dirname, '../../__fixtures__/project.pbxproj')
 );
 
 describe('ios::addFileToProject', () => {
@@ -25,12 +23,12 @@ describe('ios::addFileToProject', () => {
   });
 
   it('should add file to a project', () => {
-    const fileRef = addFileToProject(
+    const { fileRef } = addFileToProject(
       project,
-      '../../__fixtures__/linearGradient.pbxproj',
-    ).fileRef;
+      '../../__fixtures__/linearGradient.pbxproj'
+    );
     expect(
-      _.includes(Object.keys(project.pbxFileReferenceSection()), fileRef),
+      _.includes(Object.keys(project.pbxFileReferenceSection()), fileRef)
     ).toBeTruthy();
   });
 });
diff --git a/packages/local-cli/link/__tests__/ios/addProjectToLibraries-test.js b/packages/local-cli/link/__tests__/ios/addProjectToLibraries-test.js
index 9a921c217..c7deab740 100644
--- a/packages/local-cli/link/__tests__/ios/addProjectToLibraries-test.js
+++ b/packages/local-cli/link/__tests__/ios/addProjectToLibraries-test.js
@@ -8,16 +8,15 @@
  * @emails oncall+javascript_foundation
  */
 
-'use strict';
-
 const xcode = require('xcode');
 const path = require('path');
 const PbxFile = require('xcode/lib/pbxFile');
+const { last } = require('lodash');
+
 const addProjectToLibraries = require('../../ios/addProjectToLibraries');
-const last = require('lodash').last;
 
 const project = xcode.project(
-  path.join(__dirname, '../../__fixtures__/project.pbxproj'),
+  path.join(__dirname, '../../__fixtures__/project.pbxproj')
 );
 
 describe('ios::addProjectToLibraries', () => {
diff --git a/packages/local-cli/link/__tests__/ios/addSharedLibraries-test.js b/packages/local-cli/link/__tests__/ios/addSharedLibraries-test.js
index c4a262015..5c5fb181c 100644
--- a/packages/local-cli/link/__tests__/ios/addSharedLibraries-test.js
+++ b/packages/local-cli/link/__tests__/ios/addSharedLibraries-test.js
@@ -8,15 +8,13 @@
  * @emails oncall+javascript_foundation
  */
 
-'use strict';
-
 const xcode = require('xcode');
 const path = require('path');
 const addSharedLibraries = require('../../ios/addSharedLibraries');
 const getGroup = require('../../ios/getGroup');
 
 const project = xcode.project(
-  path.join(__dirname, '../../__fixtures__/project.pbxproj'),
+  path.join(__dirname, '../../__fixtures__/project.pbxproj')
 );
 
 describe('ios::addSharedLibraries', () => {
@@ -34,11 +32,11 @@ describe('ios::addSharedLibraries', () => {
     addSharedLibraries(project, ['libz.tbd']);
 
     const frameworksGroup = getGroup(project, 'Frameworks');
-    expect(frameworksGroup.children.length).toEqual(1);
+    expect(frameworksGroup.children).toHaveLength(1);
     expect(frameworksGroup.children[0].comment).toEqual('libz.tbd');
 
     addSharedLibraries(project, ['MessageUI.framework']);
-    expect(frameworksGroup.children.length).toEqual(2);
+    expect(frameworksGroup.children).toHaveLength(2);
   });
 
   it('should not add duplicate libraries to project', () => {
@@ -46,6 +44,6 @@ describe('ios::addSharedLibraries', () => {
     addSharedLibraries(project, ['libz.tbd']);
 
     const frameworksGroup = getGroup(project, 'Frameworks');
-    expect(frameworksGroup.children.length).toEqual(1);
+    expect(frameworksGroup.children).toHaveLength(1);
   });
 });
diff --git a/packages/local-cli/link/__tests__/ios/createGroup-test.js b/packages/local-cli/link/__tests__/ios/createGroup-test.js
index 6100b92d0..c96f8543b 100644
--- a/packages/local-cli/link/__tests__/ios/createGroup-test.js
+++ b/packages/local-cli/link/__tests__/ios/createGroup-test.js
@@ -8,16 +8,15 @@
  * @emails oncall+javascript_foundation
  */
 
-'use strict';
-
 const xcode = require('xcode');
 const path = require('path');
+const { last } = require('lodash');
+
 const createGroup = require('../../ios/createGroup');
 const getGroup = require('../../ios/getGroup');
-const last = require('lodash').last;
 
 const project = xcode.project(
-  path.join(__dirname, '../../__fixtures__/project.pbxproj'),
+  path.join(__dirname, '../../__fixtures__/project.pbxproj')
 );
 
 describe('ios::createGroup', () => {
@@ -50,8 +49,8 @@ describe('ios::createGroup', () => {
     const mainGroup = getGroup(project);
 
     expect(
-      mainGroup.children.filter(group => group.comment === 'Libraries').length,
-    ).toBe(1);
+      mainGroup.children.filter(group => group.comment === 'Libraries')
+    ).toHaveLength(1);
     expect(last(outerGroup.children).comment).toBe(createdGroup.name);
   });
 });
diff --git a/packages/local-cli/link/__tests__/ios/getBuildProperty-test.js b/packages/local-cli/link/__tests__/ios/getBuildProperty-test.js
index ff5c622eb..8c2618ca8 100644
--- a/packages/local-cli/link/__tests__/ios/getBuildProperty-test.js
+++ b/packages/local-cli/link/__tests__/ios/getBuildProperty-test.js
@@ -8,14 +8,12 @@
  * @emails oncall+javascript_foundation
  */
 
-'use strict';
-
 const xcode = require('xcode');
 const path = require('path');
 const getBuildProperty = require('../../ios/getBuildProperty');
 
 const project = xcode.project(
-  path.join(__dirname, '../../__fixtures__/project.pbxproj'),
+  path.join(__dirname, '../../__fixtures__/project.pbxproj')
 );
 
 describe('ios::getBuildProperty', () => {
diff --git a/packages/local-cli/link/__tests__/ios/getGroup-test.js b/packages/local-cli/link/__tests__/ios/getGroup-test.js
index a08434d26..c9f61fc80 100644
--- a/packages/local-cli/link/__tests__/ios/getGroup-test.js
+++ b/packages/local-cli/link/__tests__/ios/getGroup-test.js
@@ -8,14 +8,12 @@
  * @emails oncall+javascript_foundation
  */
 
-'use strict';
-
 const xcode = require('xcode');
-const getGroup = require('../../ios/getGroup');
 const path = require('path');
+const getGroup = require('../../ios/getGroup');
 
 const project = xcode.project(
-  path.join(__dirname, '../../__fixtures__/project.pbxproj'),
+  path.join(__dirname, '../../__fixtures__/project.pbxproj')
 );
 
 describe('ios::getGroup', () => {
@@ -31,7 +29,7 @@ describe('ios::getGroup', () => {
 
   it('should return nested group when specified', () => {
     const group = getGroup(project, 'NestedGroup/Libraries');
-    expect(group.children.length).toBe(0); // our test nested Libraries is empty
+    expect(group.children).toHaveLength(0); // our test nested Libraries is empty
     expect(group.name).toBe('Libraries');
   });
 
diff --git a/packages/local-cli/link/__tests__/ios/getHeaderSearchPath-test.js b/packages/local-cli/link/__tests__/ios/getHeaderSearchPath-test.js
index 551834607..35cb07e54 100644
--- a/packages/local-cli/link/__tests__/ios/getHeaderSearchPath-test.js
+++ b/packages/local-cli/link/__tests__/ios/getHeaderSearchPath-test.js
@@ -8,10 +8,8 @@
  * @emails oncall+javascript_foundation
  */
 
-'use strict';
-
-const getHeaderSearchPath = require('../../ios/getHeaderSearchPath');
 const path = require('path');
+const getHeaderSearchPath = require('../../ios/getHeaderSearchPath');
 
 const SRC_DIR = path.join('react-native-project', 'ios');
 
@@ -25,7 +23,7 @@ describe('ios::getHeaderSearchPath', () => {
         'react-native-project',
         'node_modules',
         'package',
-        'Gradient.h',
+        'Gradient.h'
       ),
       path.join('react-native-project', 'node_modules', 'package', 'Manager.h'),
     ];
@@ -33,7 +31,7 @@ describe('ios::getHeaderSearchPath', () => {
     const searchPath = getHeaderSearchPath(SRC_DIR, files);
 
     expect(searchPath).toBe(
-      `"${['$(SRCROOT)', '..', 'node_modules', 'package'].join(path.sep)}"`,
+      `"${['$(SRCROOT)', '..', 'node_modules', 'package'].join(path.sep)}"`
     );
   });
 
@@ -48,7 +46,7 @@ describe('ios::getHeaderSearchPath', () => {
         'package',
         'src',
         'folderA',
-        'Gradient.h',
+        'Gradient.h'
       ),
       path.join(
         'react-native-project',
@@ -56,7 +54,7 @@ describe('ios::getHeaderSearchPath', () => {
         'package',
         'src',
         'folderB',
-        'Manager.h',
+        'Manager.h'
       ),
     ];
 
@@ -64,8 +62,8 @@ describe('ios::getHeaderSearchPath', () => {
 
     expect(searchPath).toBe(
       `"${['$(SRCROOT)', '..', 'node_modules', 'package', 'src'].join(
-        path.sep,
-      )}/**"`,
+        path.sep
+      )}/**"`
     );
   });
 
@@ -80,7 +78,7 @@ describe('ios::getHeaderSearchPath', () => {
         'package',
         'src',
         'folderA',
-        'Gradient.h',
+        'Gradient.h'
       ),
       path.join(
         'react-native-project',
@@ -88,14 +86,14 @@ describe('ios::getHeaderSearchPath', () => {
         'package',
         'src',
         'folderB',
-        'Manager.h',
+        'Manager.h'
       ),
       path.join(
         'react-native-project',
         'node_modules',
         'package',
         'src',
-        'Manager.h',
+        'Manager.h'
       ),
     ];
 
@@ -103,8 +101,8 @@ describe('ios::getHeaderSearchPath', () => {
 
     expect(searchPath).toBe(
       `"${['$(SRCROOT)', '..', 'node_modules', 'package', 'src'].join(
-        path.sep,
-      )}/**"`,
+        path.sep
+      )}/**"`
     );
   });
 });
diff --git a/packages/local-cli/link/__tests__/ios/getHeadersInFolder-test.js b/packages/local-cli/link/__tests__/ios/getHeadersInFolder-test.js
index d590d6c73..c5da4d023 100644
--- a/packages/local-cli/link/__tests__/ios/getHeadersInFolder-test.js
+++ b/packages/local-cli/link/__tests__/ios/getHeadersInFolder-test.js
@@ -8,8 +8,6 @@
  * @emails oncall+javascript_foundation
  */
 
-'use strict';
-
 const getHeadersInFolder = require('../../ios/getHeadersInFolder');
 
 describe('ios::getHeadersInFolder', () => {
@@ -21,10 +19,10 @@ describe('ios::getHeadersInFolder', () => {
 
     const foundHeaders = getHeadersInFolder(process.cwd());
 
-    expect(foundHeaders.length).toBe(2);
+    expect(foundHeaders).toHaveLength(2);
 
     getHeadersInFolder(process.cwd()).forEach(headerPath => {
-      expect(headerPath).to.contain(process.cwd());
+      expect(headerPath.includes(process.cwd())).toBe(true);
     });
   });
 
@@ -43,6 +41,6 @@ describe('ios::getHeadersInFolder', () => {
       },
     });
 
-    expect(getHeadersInFolder(process.cwd()).length).to.equals(2);
+    expect(getHeadersInFolder(process.cwd())).toEqual(2);
   });
 });
diff --git a/packages/local-cli/link/__tests__/ios/getPlist-test.js b/packages/local-cli/link/__tests__/ios/getPlist-test.js
index f229af7a4..609132ad4 100644
--- a/packages/local-cli/link/__tests__/ios/getPlist-test.js
+++ b/packages/local-cli/link/__tests__/ios/getPlist-test.js
@@ -8,14 +8,12 @@
  * @emails oncall+javascript_foundation
  */
 
-'use strict';
-
 const xcode = require('xcode');
-const getPlist = require('../../ios/getPlist');
 const path = require('path');
+const getPlist = require('../../ios/getPlist');
 
 const project = xcode.project(
-  path.join(__dirname, '../../__fixtures__/project.pbxproj'),
+  path.join(__dirname, '../../__fixtures__/project.pbxproj')
 );
 
 describe('ios::getPlist', () => {
diff --git a/packages/local-cli/link/__tests__/ios/getPlistPath-test.js b/packages/local-cli/link/__tests__/ios/getPlistPath-test.js
index ae2de5914..c0fa8aef8 100644
--- a/packages/local-cli/link/__tests__/ios/getPlistPath-test.js
+++ b/packages/local-cli/link/__tests__/ios/getPlistPath-test.js
@@ -8,14 +8,12 @@
  * @emails oncall+javascript_foundation
  */
 
-'use strict';
-
 const xcode = require('xcode');
-const getPlistPath = require('../../ios/getPlistPath');
 const path = require('path');
+const getPlistPath = require('../../ios/getPlistPath');
 
 const project = xcode.project(
-  path.join(__dirname, '../../__fixtures__/project.pbxproj'),
+  path.join(__dirname, '../../__fixtures__/project.pbxproj')
 );
 
 describe('ios::getPlistPath', () => {
diff --git a/packages/local-cli/link/__tests__/ios/getTargets-test.js b/packages/local-cli/link/__tests__/ios/getTargets-test.js
index 0f1142b5e..10a8bcad4 100644
--- a/packages/local-cli/link/__tests__/ios/getTargets-test.js
+++ b/packages/local-cli/link/__tests__/ios/getTargets-test.js
@@ -8,14 +8,12 @@
  * @emails oncall+javascript_foundation
  */
 
-'use strict';
-
 const xcode = require('xcode');
-const getTargets = require('../../ios/getTargets');
 const path = require('path');
+const getTargets = require('../../ios/getTargets');
 
 const project = xcode.project(
-  path.join(__dirname, '../../__fixtures__/project.pbxproj'),
+  path.join(__dirname, '../../__fixtures__/project.pbxproj')
 );
 
 describe('ios::getTargets', () => {
@@ -25,7 +23,7 @@ describe('ios::getTargets', () => {
 
   it('should return an array of project targets', () => {
     const targets = getTargets(project);
-    expect(targets.length).toBe(2);
+    expect(targets).toHaveLength(2);
     expect(targets[0].name).toContain('Basic.app');
     expect(targets[1].name).toContain('BasicTests.xctest');
   });
diff --git a/packages/local-cli/link/__tests__/ios/hasLibraryImported-test.js b/packages/local-cli/link/__tests__/ios/hasLibraryImported-test.js
index b36fbd78d..3f495522e 100644
--- a/packages/local-cli/link/__tests__/ios/hasLibraryImported-test.js
+++ b/packages/local-cli/link/__tests__/ios/hasLibraryImported-test.js
@@ -8,14 +8,12 @@
  * @emails oncall+javascript_foundation
  */
 
-'use strict';
-
 const xcode = require('xcode');
-const hasLibraryImported = require('../../ios/hasLibraryImported');
 const path = require('path');
+const hasLibraryImported = require('../../ios/hasLibraryImported');
 
 const project = xcode.project(
-  path.join(__dirname, '../../__fixtures__/project.pbxproj'),
+  path.join(__dirname, '../../__fixtures__/project.pbxproj')
 );
 
 describe('ios::hasLibraryImported', () => {
diff --git a/packages/local-cli/link/__tests__/ios/isInstalled-test.js b/packages/local-cli/link/__tests__/ios/isInstalled-test.js
index 5998c2e51..9c4fea215 100644
--- a/packages/local-cli/link/__tests__/ios/isInstalled-test.js
+++ b/packages/local-cli/link/__tests__/ios/isInstalled-test.js
@@ -8,8 +8,6 @@
  * @emails oncall+javascript_foundation
  */
 
-'use strict';
-
 const path = require('path');
 const isInstalled = require('../../ios/isInstalled');
 
@@ -20,17 +18,17 @@ const baseProjectConfig = {
 
 describe('ios::isInstalled', () => {
   it('should return true when .xcodeproj in Libraries', () => {
-    const dependencyConfig = {projectName: 'React.xcodeproj'};
+    const dependencyConfig = { projectName: 'React.xcodeproj' };
     expect(isInstalled(baseProjectConfig, dependencyConfig)).toBeTruthy();
   });
 
   it('should return false when .xcodeproj not in Libraries', () => {
-    const dependencyConfig = {projectName: 'Missing.xcodeproj'};
+    const dependencyConfig = { projectName: 'Missing.xcodeproj' };
     expect(isInstalled(baseProjectConfig, dependencyConfig)).toBeFalsy();
   });
 
   it('should return false when `LibraryFolder` is missing', () => {
-    const dependencyConfig = {projectName: 'React.xcodeproj'};
+    const dependencyConfig = { projectName: 'React.xcodeproj' };
     const projectConfig = Object.assign({}, baseProjectConfig, {
       libraryFolder: 'Missing',
     });
diff --git a/packages/local-cli/link/__tests__/ios/mapHeaderSearchPaths-test.js b/packages/local-cli/link/__tests__/ios/mapHeaderSearchPaths-test.js
index 0be5740c2..99e3ae958 100644
--- a/packages/local-cli/link/__tests__/ios/mapHeaderSearchPaths-test.js
+++ b/packages/local-cli/link/__tests__/ios/mapHeaderSearchPaths-test.js
@@ -8,14 +8,12 @@
  * @emails oncall+javascript_foundation
  */
 
-'use strict';
-
 const xcode = require('xcode');
-const mapHeaderSearchPaths = require('../../ios/mapHeaderSearchPaths');
 const path = require('path');
+const mapHeaderSearchPaths = require('../../ios/mapHeaderSearchPaths');
 
 const project = xcode.project(
-  path.join(__dirname, '../../__fixtures__/project.pbxproj'),
+  path.join(__dirname, '../../__fixtures__/project.pbxproj')
 );
 
 describe('ios::mapHeaderSearchPaths', () => {
@@ -31,7 +29,7 @@ describe('ios::mapHeaderSearchPaths', () => {
     const callback = jest.fn();
     mapHeaderSearchPaths(project, callback);
 
-    expect(callback.mock.calls.length).toBe(2);
+    expect(callback.mock.calls).toHaveLength(2);
   });
 
   it('calls the function with an array of paths, given a project with one', () => {
@@ -41,7 +39,7 @@ describe('ios::mapHeaderSearchPaths', () => {
     const paths = callback.mock.calls[0][0];
 
     expect(paths instanceof Array).toBe(true);
-    expect(paths.length).toBe(1);
+    expect(paths).toHaveLength(1);
     expect(paths[0]).toBe('"$(inherited)"');
   });
 });
diff --git a/packages/local-cli/link/__tests__/ios/removeProjectFromLibraries-test.js b/packages/local-cli/link/__tests__/ios/removeProjectFromLibraries-test.js
index 1abf072a1..e21f84d45 100644
--- a/packages/local-cli/link/__tests__/ios/removeProjectFromLibraries-test.js
+++ b/packages/local-cli/link/__tests__/ios/removeProjectFromLibraries-test.js
@@ -8,17 +8,16 @@
  * @emails oncall+javascript_foundation
  */
 
-'use strict';
-
 const xcode = require('xcode');
 const PbxFile = require('xcode/lib/pbxFile');
+const path = require('path');
+const { last } = require('lodash');
+
 const addProjectToLibraries = require('../../ios/addProjectToLibraries');
 const removeProjectFromLibraries = require('../../ios/removeProjectFromLibraries');
-const last = require('lodash').last;
-const path = require('path');
 
 const project = xcode.project(
-  path.join(__dirname, '../../__fixtures__/project.pbxproj'),
+  path.join(__dirname, '../../__fixtures__/project.pbxproj')
 );
 
 describe('ios::removeProjectFromLibraries', () => {
@@ -27,7 +26,7 @@ describe('ios::removeProjectFromLibraries', () => {
 
     addProjectToLibraries(
       project.pbxGroupByName('Libraries'),
-      new PbxFile('fakePath'),
+      new PbxFile('fakePath')
     );
   });
 
diff --git a/packages/local-cli/link/__tests__/ios/removeProjectFromProject-test.js b/packages/local-cli/link/__tests__/ios/removeProjectFromProject-test.js
index 257e9f0e7..a1a9ea1ef 100644
--- a/packages/local-cli/link/__tests__/ios/removeProjectFromProject-test.js
+++ b/packages/local-cli/link/__tests__/ios/removeProjectFromProject-test.js
@@ -8,16 +8,14 @@
  * @emails oncall+javascript_foundation
  */
 
-'use strict';
-
 const xcode = require('xcode');
 const pbxFile = require('xcode/lib/pbxFile');
+const path = require('path');
 const addFileToProject = require('../../ios/addFileToProject');
 const removeProjectFromProject = require('../../ios/removeProjectFromProject');
-const path = require('path');
 
 const project = xcode.project(
-  path.join(__dirname, '../../__fixtures__/project.pbxproj'),
+  path.join(__dirname, '../../__fixtures__/project.pbxproj')
 );
 const filePath = '../../__fixtures__/linearGradient.pbxproj';
 
@@ -29,7 +27,7 @@ describe('ios::addFileToProject', () => {
 
   it('should return removed file', () => {
     expect(
-      removeProjectFromProject(project, filePath) instanceof pbxFile,
+      removeProjectFromProject(project, filePath) instanceof pbxFile
     ).toBeTruthy();
   });
 
diff --git a/packages/local-cli/link/__tests__/ios/removeSharedLibrary-test.js b/packages/local-cli/link/__tests__/ios/removeSharedLibrary-test.js
index 5f983e551..f119fea97 100644
--- a/packages/local-cli/link/__tests__/ios/removeSharedLibrary-test.js
+++ b/packages/local-cli/link/__tests__/ios/removeSharedLibrary-test.js
@@ -8,8 +8,6 @@
  * @emails oncall+javascript_foundation
  */
 
-'use strict';
-
 const xcode = require('xcode');
 const path = require('path');
 const addSharedLibraries = require('../../ios/addSharedLibraries');
@@ -17,7 +15,7 @@ const removeSharedLibraries = require('../../ios/removeSharedLibraries');
 const getGroup = require('../../ios/getGroup');
 
 const project = xcode.project(
-  path.join(__dirname, '../../__fixtures__/project.pbxproj'),
+  path.join(__dirname, '../../__fixtures__/project.pbxproj')
 );
 
 describe('ios::removeSharedLibraries', () => {
@@ -30,7 +28,7 @@ describe('ios::removeSharedLibraries', () => {
     removeSharedLibraries(project, ['libc++.tbd']);
 
     const frameworksGroup = getGroup(project, 'Frameworks');
-    expect(frameworksGroup.children.length).toEqual(1);
+    expect(frameworksGroup.children).toHaveLength(1);
     expect(frameworksGroup.children[0].comment).toEqual('libz.tbd');
   });
 
@@ -38,6 +36,6 @@ describe('ios::removeSharedLibraries', () => {
     removeSharedLibraries(project, ['libxml2.tbd']);
 
     const frameworksGroup = getGroup(project, 'Frameworks');
-    expect(frameworksGroup.children.length).toEqual(2);
+    expect(frameworksGroup.children).toHaveLength(2);
   });
 });
diff --git a/packages/local-cli/link/__tests__/ios/writePlist-test.js b/packages/local-cli/link/__tests__/ios/writePlist-test.js
index 36afc2255..c21011a8d 100644
--- a/packages/local-cli/link/__tests__/ios/writePlist-test.js
+++ b/packages/local-cli/link/__tests__/ios/writePlist-test.js
@@ -8,10 +8,6 @@
  * @emails oncall+javascript_foundation
  */
 
-'use strict';
-
-const getPlistPath = require('../../ios/getPlistPath');
-
 jest.mock('path');
 jest.mock('fs');
 jest.mock('../../ios/getPlistPath', () => jest.fn(() => null));
@@ -20,6 +16,7 @@ const { readFileSync } = jest.requireActual('fs');
 const fs = require('fs');
 
 const xcode = require('xcode');
+const getPlistPath = require('../../ios/getPlistPath');
 const writePlist = require('../../ios/writePlist');
 
 const realPath = jest.requireActual('path');
@@ -51,7 +48,10 @@ describe('ios::writePlist', () => {
     getPlistPath.mockImplementation(() => '/Basic/Info.plist');
     writePlist(project, '/', plist);
     const infoPlist = readFileSync(infoPlistPath).toString();
-    expect(fs.writeFileSync).toHaveBeenCalledWith('/Basic/Info.plist', infoPlist);
+    expect(fs.writeFileSync).toHaveBeenCalledWith(
+      '/Basic/Info.plist',
+      infoPlist
+    );
   });
 
   it('when plistPath is null it should return null', () => {
diff --git a/packages/local-cli/link/__tests__/link-test.js b/packages/local-cli/link/__tests__/link-test.js
index 6e9d71141..0f80fb7a9 100644
--- a/packages/local-cli/link/__tests__/link-test.js
+++ b/packages/local-cli/link/__tests__/link-test.js
@@ -8,11 +8,9 @@
  * @emails oncall+javascript_foundation
  */
 
-'use strict';
-
 const log = require('npmlog');
 
-jest.setMock('chalk', {grey: str => str});
+jest.setMock('chalk', { grey: str => str });
 
 const context = {
   root: process.cwd(),
@@ -31,14 +29,16 @@ describe('link', () => {
   });
 
   it('should accept a name of a dependency to link', done => {
-    const getDependencyConfig = jest.fn(() => [{
-      config: {
-        ios: null,
-        android: null,
+    const getDependencyConfig = jest.fn(() => [
+      {
+        config: {
+          ios: null,
+          android: null,
+        },
+        assets: [],
+        commands: {},
       },
-      assets: [],
-      commands: {}
-    }]);
+    ]);
 
     jest.setMock('../getDependencyConfig', getDependencyConfig);
 
@@ -52,23 +52,23 @@ describe('link', () => {
   });
 
   it('should accept the name of a dependency with a scope / tag', async () => {
-    const getDependencyConfig = jest.fn(() => [{
-      config: {
-        ios: null,
-        android: null,
+    const getDependencyConfig = jest.fn(() => [
+      {
+        config: {
+          ios: null,
+          android: null,
+        },
+        assets: [],
+        commands: {},
       },
-      assets: [],
-      commands: {}
-    }]);
+    ]);
 
     jest.setMock('../getDependencyConfig', getDependencyConfig);
 
     const link = require('../link').func;
     await link(['@scope/something@latest'], context);
-    
-    expect(getDependencyConfig.mock.calls[0][2]).toEqual([
-      '@scope/something',
-    ]);
+
+    expect(getDependencyConfig.mock.calls[0][2]).toEqual(['@scope/something']);
   });
 
   it('should register native module when android/ios projects are present', done => {
@@ -80,14 +80,16 @@ describe('link', () => {
       android: {},
     }));
 
-    const getDependencyConfig = jest.fn(() => [{
-      config: {
-        ios: {},
-        android: {},
+    const getDependencyConfig = jest.fn(() => [
+      {
+        config: {
+          ios: {},
+          android: {},
+        },
+        assets: [],
+        commands: { prelink, postlink },
       },
-      assets: [],
-      commands: {prelink, postlink}
-    }]);
+    ]);
 
     jest.setMock('../getDependencyConfig', getDependencyConfig);
 
@@ -95,21 +97,21 @@ describe('link', () => {
 
     jest.setMock('../android/isInstalled.js', jest.fn().mockReturnValue(false));
     jest.setMock('../android/registerNativeModule.js', registerNativeModule);
-    
+
     jest.setMock('../ios/isInstalled.js', jest.fn().mockReturnValue(false));
     jest.setMock('../ios/registerNativeModule.js', registerNativeModule);
 
     const link = require('../link').func;
 
     link(['react-native-blur'], context).then(() => {
-      expect(registerNativeModule.mock.calls.length).toBe(2);
+      expect(registerNativeModule.mock.calls).toHaveLength(2);
 
       expect(prelink.mock.invocationCallOrder[0]).toBeLessThan(
-        registerNativeModule.mock.invocationCallOrder[0],
+        registerNativeModule.mock.invocationCallOrder[0]
       );
 
       expect(postlink.mock.invocationCallOrder[0]).toBeGreaterThan(
-        registerNativeModule.mock.invocationCallOrder[0],
+        registerNativeModule.mock.invocationCallOrder[0]
       );
 
       done();
@@ -119,24 +121,26 @@ describe('link', () => {
   it('should copy assets from both project and dependencies projects', done => {
     const dependencyAssets = ['Fonts/Font.ttf'];
     const projectAssets = ['Fonts/FontC.ttf'];
-    
+
     jest.setMock('../getProjectConfig', () => ({
       ios: {},
       android: {},
     }));
 
-    jest.setMock('../getDependencyConfig', () => [{
-      config: {
-        ios: {},
-        android: {},
+    jest.setMock('../getDependencyConfig', () => [
+      {
+        config: {
+          ios: {},
+          android: {},
+        },
+        assets: dependencyAssets,
+        commands: {},
       },
-      assets: dependencyAssets,
-      commands: {}
-    }]);
+    ]);
 
     jest.setMock('../android/isInstalled.js', jest.fn().mockReturnValue(false));
     jest.setMock('../android/registerNativeModule.js', jest.fn());
-    
+
     jest.setMock('../ios/isInstalled.js', jest.fn().mockReturnValue(false));
     jest.setMock('../ios/registerNativeModule.js', jest.fn());
 
@@ -150,9 +154,9 @@ describe('link', () => {
     const link = require('../link').func;
 
     link(['react-native-blur'], context).then(() => {
-      expect(copyAssets.mock.calls.length).toBe(2);
+      expect(copyAssets.mock.calls).toHaveLength(2);
       expect(copyAssets.mock.calls[0][0]).toEqual(
-        projectAssets.concat(dependencyAssets),
+        projectAssets.concat(dependencyAssets)
       );
       jest.unmock('../../core/getAssets');
       done();
@@ -165,14 +169,16 @@ describe('link', () => {
       android: {},
     }));
 
-    const getDependencyConfig = jest.fn(() => [{
-      config: {
-        ios: {},
-        android: {},
+    const getDependencyConfig = jest.fn(() => [
+      {
+        config: {
+          ios: {},
+          android: {},
+        },
+        assets: [],
+        commands: {},
       },
-      assets: [],
-      commands: {}
-    }]);
+    ]);
 
     jest.setMock('../getDependencyConfig', getDependencyConfig);
 
@@ -180,14 +186,14 @@ describe('link', () => {
 
     jest.setMock('../android/isInstalled.js', jest.fn().mockReturnValue(true));
     jest.setMock('../android/registerNativeModule.js', registerNativeModule);
-    
+
     jest.setMock('../ios/isInstalled.js', jest.fn().mockReturnValue(true));
     jest.setMock('../ios/registerNativeModule.js', registerNativeModule);
 
     const link = require('../link').func;
 
     link(['react-native-blur'], context).then(() => {
-      expect(registerNativeModule.mock.calls.length).toEqual(0);
+      expect(registerNativeModule.mock.calls).toHaveLength(0);
       done();
     });
   });
@@ -205,35 +211,37 @@ describe('link', () => {
       isInstalled: () => false,
       register: registerNativeModule,
     });
-  
-    const getDependencyConfig = jest.fn(() => [{
-      config: {
-        ios: {},
-        android: {},
-        windows: {}
+
+    const getDependencyConfig = jest.fn(() => [
+      {
+        config: {
+          ios: {},
+          android: {},
+          windows: {},
+        },
+        assets: [],
+        commands: {},
       },
-      assets: [],
-      commands: {}
-    }]);
+    ]);
 
     jest.setMock('../../core/getPlatforms', () => ({
-      ios: {linkConfig: require('../ios')},
-      android: {linkConfig: require('../android')},
-      windows: {linkConfig: genericLinkConfig},
+      ios: { linkConfig: require('../ios') },
+      android: { linkConfig: require('../android') },
+      windows: { linkConfig: genericLinkConfig },
     }));
 
     jest.setMock('../getDependencyConfig', getDependencyConfig);
 
     jest.setMock('../android/isInstalled.js', jest.fn().mockReturnValue(true));
     jest.setMock('../android/registerNativeModule.js', registerNativeModule);
-    
+
     jest.setMock('../ios/isInstalled.js', jest.fn().mockReturnValue(true));
     jest.setMock('../ios/registerNativeModule.js', registerNativeModule);
 
     const link = require('../link').func;
 
     link(['react-native-blur'], context).then(() => {
-      expect(registerNativeModule.mock.calls.length).toBe(1);
+      expect(registerNativeModule.mock.calls).toHaveLength(1);
       done();
     });
   });
diff --git a/packages/local-cli/link/__tests__/pods/findLineToAddPod-test.js b/packages/local-cli/link/__tests__/pods/findLineToAddPod-test.js
index d27b341dd..c04ad4ad6 100644
--- a/packages/local-cli/link/__tests__/pods/findLineToAddPod-test.js
+++ b/packages/local-cli/link/__tests__/pods/findLineToAddPod-test.js
@@ -8,8 +8,6 @@
  * @emails oncall+javascript_foundation
  */
 
-'use strict';
-
 const path = require('path');
 const findLineToAddPod = require('../../pods/findLineToAddPod');
 const readPodfile = require('../../pods/readPodfile');
@@ -21,30 +19,30 @@ describe('pods::findLineToAddPod', () => {
   it('returns null if file is not Podfile', () => {
     const podfile = readPodfile(path.join(PODFILES_PATH, '../Info.plist'));
     expect(
-      findLineToAddPod(podfile, LINE_AFTER_TARGET_IN_TEST_PODFILE),
+      findLineToAddPod(podfile, LINE_AFTER_TARGET_IN_TEST_PODFILE)
     ).toBeNull();
   });
 
   it('returns correct line number for Simple Podfile', () => {
     const podfile = readPodfile(path.join(PODFILES_PATH, 'PodfileSimple'));
     expect(
-      findLineToAddPod(podfile, LINE_AFTER_TARGET_IN_TEST_PODFILE),
-    ).toEqual({line: 7, indentation: 2});
+      findLineToAddPod(podfile, LINE_AFTER_TARGET_IN_TEST_PODFILE)
+    ).toEqual({ line: 7, indentation: 2 });
   });
 
   it('returns correct line number for Podfile with target', () => {
     const podfile = readPodfile(path.join(PODFILES_PATH, 'PodfileWithTarget'));
     expect(
-      findLineToAddPod(podfile, LINE_AFTER_TARGET_IN_TEST_PODFILE),
-    ).toEqual({line: 21, indentation: 2});
+      findLineToAddPod(podfile, LINE_AFTER_TARGET_IN_TEST_PODFILE)
+    ).toEqual({ line: 21, indentation: 2 });
   });
 
   it('returns correct line number for Podfile with function', () => {
     const podfile = readPodfile(
-      path.join(PODFILES_PATH, 'PodfileWithFunction'),
+      path.join(PODFILES_PATH, 'PodfileWithFunction')
     );
     expect(
-      findLineToAddPod(podfile, LINE_AFTER_TARGET_IN_TEST_PODFILE),
-    ).toEqual({line: 26, indentation: 2});
+      findLineToAddPod(podfile, LINE_AFTER_TARGET_IN_TEST_PODFILE)
+    ).toEqual({ line: 26, indentation: 2 });
   });
 });
diff --git a/packages/local-cli/link/__tests__/pods/findMarkedLinesInPodfile-test.js b/packages/local-cli/link/__tests__/pods/findMarkedLinesInPodfile-test.js
index 2c9d8decd..dd0ff0f34 100644
--- a/packages/local-cli/link/__tests__/pods/findMarkedLinesInPodfile-test.js
+++ b/packages/local-cli/link/__tests__/pods/findMarkedLinesInPodfile-test.js
@@ -8,8 +8,6 @@
  * @emails oncall+javascript_foundation
  */
 
-'use strict';
-
 const path = require('path');
 const readPodfile = require('../../pods/readPodfile');
 const findMarkedLinesInPodfile = require('../../pods/findMarkedLinesInPodfile');
@@ -26,18 +24,18 @@ describe('pods::findMarkedLinesInPodfile', () => {
   it('returns empty array for Simple Podfile', () => {
     const podfile = readPodfile(path.join(PODFILES_PATH, 'PodfileSimple'));
     expect(
-      findMarkedLinesInPodfile(podfile, LINE_AFTER_TARGET_IN_TEST_PODFILE),
+      findMarkedLinesInPodfile(podfile, LINE_AFTER_TARGET_IN_TEST_PODFILE)
     ).toEqual([]);
   });
 
   it('returns correct line numbers for Podfile with marker', () => {
     const podfile = readPodfile(path.join(PODFILES_PATH, 'PodfileWithMarkers'));
     const expectedObject = [
-      {line: 18, indentation: 2},
-      {line: 31, indentation: 4},
+      { line: 18, indentation: 2 },
+      { line: 31, indentation: 4 },
     ];
     expect(
-      findMarkedLinesInPodfile(podfile, LINE_AFTER_TARGET_IN_TEST_PODFILE),
+      findMarkedLinesInPodfile(podfile, LINE_AFTER_TARGET_IN_TEST_PODFILE)
     ).toEqual(expectedObject);
   });
 });
diff --git a/packages/local-cli/link/__tests__/pods/findPodTargetLine-test.js b/packages/local-cli/link/__tests__/pods/findPodTargetLine-test.js
index 6b7b360e0..6b0ff45a3 100644
--- a/packages/local-cli/link/__tests__/pods/findPodTargetLine-test.js
+++ b/packages/local-cli/link/__tests__/pods/findPodTargetLine-test.js
@@ -8,8 +8,6 @@
  * @emails oncall+javascript_foundation
  */
 
-'use strict';
-
 const path = require('path');
 const findPodTargetLine = require('../../pods/findPodTargetLine');
 const readPodfile = require('../../pods/readPodfile');
@@ -27,7 +25,7 @@ describe('pods::findPodTargetLine', () => {
     expect(findPodTargetLine(podfile, 'invalidName')).toBeNull();
   });
 
-  it('returns null if there is not matching project name', () => {
+  it('returns correct line if there is a matching project', () => {
     const podfile = readPodfile(path.join(PODFILES_PATH, 'PodfileSimple'));
     expect(findPodTargetLine(podfile, 'Testing')).toBe(4);
   });
diff --git a/packages/local-cli/link/__tests__/pods/isInstalled-test.js b/packages/local-cli/link/__tests__/pods/isInstalled-test.js
index dbf484574..74c0708f5 100644
--- a/packages/local-cli/link/__tests__/pods/isInstalled-test.js
+++ b/packages/local-cli/link/__tests__/pods/isInstalled-test.js
@@ -8,8 +8,6 @@
  * @emails oncall+javascript_foundation
  */
 
-'use strict';
-
 const path = require('path');
 const isInstalled = require('../../pods/isInstalled');
 
@@ -17,26 +15,28 @@ const PODFILES_PATH = path.join(__dirname, '../../__fixtures__/pods');
 
 describe('pods::isInstalled', () => {
   it('returns false if pod is missing', () => {
-    const project = {podfile: path.join(PODFILES_PATH, 'PodfileSimple')};
-    const podspecName = {podspec: 'NotExisting'};
+    const project = { podfile: path.join(PODFILES_PATH, 'PodfileSimple') };
+    const podspecName = { podspec: 'NotExisting' };
     expect(isInstalled(project, podspecName)).toBe(false);
   });
 
   it('returns true for existing pod with version number', () => {
-    const project = {podfile: path.join(PODFILES_PATH, 'PodfileSimple')};
-    const podspecName = {podspec: 'TestPod'};
+    const project = { podfile: path.join(PODFILES_PATH, 'PodfileSimple') };
+    const podspecName = { podspec: 'TestPod' };
     expect(isInstalled(project, podspecName)).toBe(true);
   });
 
   it('returns true for existing pod with path', () => {
-    const project = {podfile: path.join(PODFILES_PATH, 'PodfileWithTarget')};
-    const podspecName = {podspec: 'Yoga'};
+    const project = { podfile: path.join(PODFILES_PATH, 'PodfileWithTarget') };
+    const podspecName = { podspec: 'Yoga' };
     expect(isInstalled(project, podspecName)).toBe(true);
   });
 
   it('returns true for existing pod with multiline definition', () => {
-    const project = {podfile: path.join(PODFILES_PATH, 'PodfileWithFunction')};
-    const podspecName = {podspec: 'React'};
+    const project = {
+      podfile: path.join(PODFILES_PATH, 'PodfileWithFunction'),
+    };
+    const podspecName = { podspec: 'React' };
     expect(isInstalled(project, podspecName)).toBe(true);
   });
 });
diff --git a/packages/local-cli/link/__tests__/pods/removePodEntry-test.js b/packages/local-cli/link/__tests__/pods/removePodEntry-test.js
index 83106805c..18eb1c1cf 100644
--- a/packages/local-cli/link/__tests__/pods/removePodEntry-test.js
+++ b/packages/local-cli/link/__tests__/pods/removePodEntry-test.js
@@ -8,8 +8,6 @@
  * @emails oncall+javascript_foundation
  */
 
-'use strict';
-
 const path = require('path');
 const removePodEntry = require('../../pods/removePodEntry');
 const readPodfile = require('../../pods/readPodfile');
@@ -18,15 +16,15 @@ const PODFILES_PATH = path.join(__dirname, '../../__fixtures__/pods');
 
 describe('pods::removePodEntry', () => {
   it('should remove one line from Podfile with TestPod', () => {
-    const {podfileContent, podLinesCount} = readTestPodFile('PodfileSimple');
+    const { podfileContent, podLinesCount } = readTestPodFile('PodfileSimple');
     const podFileWithRemoved = removePodEntry(podfileContent, 'TestPod');
     const newLineCount = podFileWithRemoved.split('\n').length;
     expect(newLineCount).toBe(podLinesCount - 1);
   });
 
   it('should remove one line from Podfile with Yoga', () => {
-    const {podfileContent, podLinesCount} = readTestPodFile(
-      'PodfileWithTarget',
+    const { podfileContent, podLinesCount } = readTestPodFile(
+      'PodfileWithTarget'
     );
     const podFileWithRemoved = removePodEntry(podfileContent, 'Yoga');
     const newLineCount = podFileWithRemoved.split('\n').length;
@@ -34,8 +32,8 @@ describe('pods::removePodEntry', () => {
   });
 
   it('should remove whole reference to React pod from Podfile', () => {
-    const {podfileContent, podLinesCount} = readTestPodFile(
-      'PodfileWithTarget',
+    const { podfileContent, podLinesCount } = readTestPodFile(
+      'PodfileWithTarget'
     );
     const podFileWithRemoved = removePodEntry(podfileContent, 'React');
     const newLineCount = podFileWithRemoved.split('\n').length;
diff --git a/packages/local-cli/link/__tests__/promiseWaterfall-test.js b/packages/local-cli/link/__tests__/promiseWaterfall-test.js
index 3507ce991..5a6cfd741 100644
--- a/packages/local-cli/link/__tests__/promiseWaterfall-test.js
+++ b/packages/local-cli/link/__tests__/promiseWaterfall-test.js
@@ -8,8 +8,6 @@
  * @emails oncall+javascript_foundation
  */
 
-'use strict';
-
 const promiseWaterfall = require('../promiseWaterfall');
 
 describe('promiseWaterfall', () => {
@@ -20,7 +18,7 @@ describe('promiseWaterfall', () => {
 
     // Check that tasks[0] is executed before tasks[1].
     expect(tasks[0].mock.invocationCallOrder[0]).toBeLessThan(
-      tasks[1].mock.invocationCallOrder[0],
+      tasks[1].mock.invocationCallOrder[0]
     );
   });
 
@@ -41,7 +39,7 @@ describe('promiseWaterfall', () => {
 
     promiseWaterfall(tasks).catch(err => {
       expect(err).toEqual(error);
-      expect(tasks[1].mock.calls.length).toEqual(0);
+      expect(tasks[1].mock.calls).toHaveLength(0);
       done();
     });
   });
diff --git a/packages/local-cli/link/android/copyAssets.js b/packages/local-cli/link/android/copyAssets.js
index 4b58f46fb..36d54c381 100644
--- a/packages/local-cli/link/android/copyAssets.js
+++ b/packages/local-cli/link/android/copyAssets.js
@@ -23,7 +23,7 @@ module.exports = function copyAssetsAndroid(files, project) {
   (assets.font || []).forEach(asset =>
     fs.copySync(
       asset,
-      path.join(project.assetsPath, 'fonts', path.basename(asset)),
-    ),
+      path.join(project.assetsPath, 'fonts', path.basename(asset))
+    )
   );
 };
diff --git a/packages/local-cli/link/android/index.js b/packages/local-cli/link/android/index.js
index d8b8f5add..0e070d783 100644
--- a/packages/local-cli/link/android/index.js
+++ b/packages/local-cli/link/android/index.js
@@ -7,7 +7,7 @@
  * @format
  */
 
-module.exports = function() {
+module.exports = function getAndroidLinkConfig() {
   return {
     isInstalled: require('./isInstalled'),
     register: require('./registerNativeModule'),
diff --git a/packages/local-cli/link/android/patches/applyParams.js b/packages/local-cli/link/android/patches/applyParams.js
index 11b66bef2..c34d226ed 100644
--- a/packages/local-cli/link/android/patches/applyParams.js
+++ b/packages/local-cli/link/android/patches/applyParams.js
@@ -11,7 +11,7 @@ const toCamelCase = require('lodash').camelCase;
 
 module.exports = function applyParams(str, params, prefix) {
   return str.replace(/\$\{(\w+)\}/g, (pattern, param) => {
-    const name = toCamelCase(prefix) + '_' + param;
+    const name = `${toCamelCase(prefix)}_${param}`;
 
     return params[param] ? `getResources().getString(R.string.${name})` : null;
   });
diff --git a/packages/local-cli/link/android/patches/applyPatch.js b/packages/local-cli/link/android/patches/applyPatch.js
index fd17c80b2..51205e8e4 100644
--- a/packages/local-cli/link/android/patches/applyPatch.js
+++ b/packages/local-cli/link/android/patches/applyPatch.js
@@ -14,6 +14,6 @@ module.exports = function applyPatch(file, patch) {
     file,
     fs
       .readFileSync(file, 'utf8')
-      .replace(patch.pattern, match => `${match}${patch.patch}`),
+      .replace(patch.pattern, match => `${match}${patch.patch}`)
   );
 };
diff --git a/packages/local-cli/link/android/patches/makeBuildPatch.js b/packages/local-cli/link/android/patches/makeBuildPatch.js
index db8feb5a8..3572e09c4 100644
--- a/packages/local-cli/link/android/patches/makeBuildPatch.js
+++ b/packages/local-cli/link/android/patches/makeBuildPatch.js
@@ -12,7 +12,7 @@ const normalizeProjectName = require('./normalizeProjectName');
 module.exports = function makeBuildPatch(name) {
   const normalizedProjectName = normalizeProjectName(name);
   const installPattern = new RegExp(
-    `\\s{4}(implementation)(\\(|\\s)(project)\\(\\\':${normalizedProjectName}\\\'\\)(\\)|\\s)`,
+    `\\s{4}(implementation)(\\(|\\s)(project)\\(\\':${normalizedProjectName}\\'\\)(\\)|\\s)`
   );
 
   return {
diff --git a/packages/local-cli/link/android/patches/makeImportPatch.js b/packages/local-cli/link/android/patches/makeImportPatch.js
index 983f2a4e0..7f190d91d 100644
--- a/packages/local-cli/link/android/patches/makeImportPatch.js
+++ b/packages/local-cli/link/android/patches/makeImportPatch.js
@@ -10,6 +10,6 @@
 module.exports = function makeImportPatch(packageImportPath) {
   return {
     pattern: 'import com.facebook.react.ReactApplication;',
-    patch: '\n' + packageImportPath,
+    patch: `\n${packageImportPath}`,
   };
 };
diff --git a/packages/local-cli/link/android/patches/makePackagePatch.js b/packages/local-cli/link/android/patches/makePackagePatch.js
index a4791ef5b..7c1698104 100644
--- a/packages/local-cli/link/android/patches/makePackagePatch.js
+++ b/packages/local-cli/link/android/patches/makePackagePatch.js
@@ -14,6 +14,6 @@ module.exports = function makePackagePatch(packageInstance, params, prefix) {
 
   return {
     pattern: 'new MainReactPackage()',
-    patch: ',\n            ' + processedInstance,
+    patch: `,\n            ${processedInstance}`,
   };
 };
diff --git a/packages/local-cli/link/android/patches/makeSettingsPatch.js b/packages/local-cli/link/android/patches/makeSettingsPatch.js
index a6bf7ca2b..43fc36f56 100644
--- a/packages/local-cli/link/android/patches/makeSettingsPatch.js
+++ b/packages/local-cli/link/android/patches/makeSettingsPatch.js
@@ -13,11 +13,11 @@ const normalizeProjectName = require('./normalizeProjectName');
 module.exports = function makeSettingsPatch(
   name,
   androidConfig,
-  projectConfig,
+  projectConfig
 ) {
-  var projectDir = path.relative(
+  const projectDir = path.relative(
     path.dirname(projectConfig.settingsGradlePath),
-    androidConfig.sourceDir,
+    androidConfig.sourceDir
   );
   const normalizedProjectName = normalizeProjectName(name);
 
diff --git a/packages/local-cli/link/android/patches/makeStringsPatch.js b/packages/local-cli/link/android/patches/makeStringsPatch.js
index efda88671..17838f624 100644
--- a/packages/local-cli/link/android/patches/makeStringsPatch.js
+++ b/packages/local-cli/link/android/patches/makeStringsPatch.js
@@ -11,14 +11,14 @@ const toCamelCase = require('lodash').camelCase;
 
 module.exports = function makeStringsPatch(params, prefix) {
   const values = Object.keys(params).map(param => {
-    const name = toCamelCase(prefix) + '_' + param;
+    const name = `${toCamelCase(prefix)}_${param}`;
     return (
       '    ' +
       `<string moduleConfig="true" name="${name}">${params[param]}</string>`
     );
   });
 
-  const patch = values.length > 0 ? values.join('\n') + '\n' : '';
+  const patch = values.length > 0 ? `${values.join('\n')}\n` : '';
 
   return {
     pattern: '<resources>\n',
diff --git a/packages/local-cli/link/android/patches/revokePatch.js b/packages/local-cli/link/android/patches/revokePatch.js
index 070972e42..56e612660 100644
--- a/packages/local-cli/link/android/patches/revokePatch.js
+++ b/packages/local-cli/link/android/patches/revokePatch.js
@@ -12,6 +12,6 @@ const fs = require('fs');
 module.exports = function revokePatch(file, patch) {
   fs.writeFileSync(
     file,
-    fs.readFileSync(file, 'utf8').replace(patch.patch, ''),
+    fs.readFileSync(file, 'utf8').replace(patch.patch, '')
   );
 };
diff --git a/packages/local-cli/link/android/registerNativeModule.js b/packages/local-cli/link/android/registerNativeModule.js
index 67ddfc7eb..1fe3484bd 100644
--- a/packages/local-cli/link/android/registerNativeModule.js
+++ b/packages/local-cli/link/android/registerNativeModule.js
@@ -18,13 +18,13 @@ module.exports = function registerNativeAndroidModule(
   name,
   androidConfig,
   params,
-  projectConfig,
+  projectConfig
 ) {
   const buildPatch = makeBuildPatch(name);
 
   applyPatch(
     projectConfig.settingsGradlePath,
-    makeSettingsPatch(name, androidConfig, projectConfig),
+    makeSettingsPatch(name, androidConfig, projectConfig)
   );
 
   applyPatch(projectConfig.buildGradlePath, buildPatch);
@@ -32,11 +32,11 @@ module.exports = function registerNativeAndroidModule(
 
   applyPatch(
     projectConfig.mainFilePath,
-    makePackagePatch(androidConfig.packageInstance, params, name),
+    makePackagePatch(androidConfig.packageInstance, params, name)
   );
 
   applyPatch(
     projectConfig.mainFilePath,
-    makeImportPatch(androidConfig.packageImportPath),
+    makeImportPatch(androidConfig.packageImportPath)
   );
 };
diff --git a/packages/local-cli/link/android/unlinkAssets.js b/packages/local-cli/link/android/unlinkAssets.js
index fc6f7db39..3f5c8bebd 100644
--- a/packages/local-cli/link/android/unlinkAssets.js
+++ b/packages/local-cli/link/android/unlinkAssets.js
@@ -24,7 +24,7 @@ module.exports = function unlinkAssetsAndroid(files, project) {
     const filePath = path.join(
       project.assetsPath,
       'fonts',
-      path.basename(file),
+      path.basename(file)
     );
     if (fs.existsSync(filePath)) {
       fs.unlinkSync(filePath);
diff --git a/packages/local-cli/link/android/unregisterNativeModule.js b/packages/local-cli/link/android/unregisterNativeModule.js
index 27aa977a3..53bbbc522 100644
--- a/packages/local-cli/link/android/unregisterNativeModule.js
+++ b/packages/local-cli/link/android/unregisterNativeModule.js
@@ -20,22 +20,22 @@ const makePackagePatch = require('./patches/makePackagePatch');
 module.exports = function unregisterNativeAndroidModule(
   name,
   androidConfig,
-  projectConfig,
+  projectConfig
 ) {
   const buildPatch = makeBuildPatch(name);
   const strings = fs.readFileSync(projectConfig.stringsPath, 'utf8');
-  var params = {};
+  const params = {};
 
   strings.replace(
     /moduleConfig="true" name="(\w+)">(.*)</g,
     (_, param, value) => {
       params[param.slice(toCamelCase(name).length + 1)] = value;
-    },
+    }
   );
 
   revokePatch(
     projectConfig.settingsGradlePath,
-    makeSettingsPatch(name, androidConfig, projectConfig),
+    makeSettingsPatch(name, androidConfig, projectConfig)
   );
 
   revokePatch(projectConfig.buildGradlePath, buildPatch);
@@ -43,11 +43,11 @@ module.exports = function unregisterNativeAndroidModule(
 
   revokePatch(
     projectConfig.mainFilePath,
-    makePackagePatch(androidConfig.packageInstance, params, name),
+    makePackagePatch(androidConfig.packageInstance, params, name)
   );
 
   revokePatch(
     projectConfig.mainFilePath,
-    makeImportPatch(androidConfig.packageImportPath),
+    makeImportPatch(androidConfig.packageImportPath)
   );
 };
diff --git a/packages/local-cli/link/getDependencyConfig.js b/packages/local-cli/link/getDependencyConfig.js
index e241be317..673e2f1df 100644
--- a/packages/local-cli/link/getDependencyConfig.js
+++ b/packages/local-cli/link/getDependencyConfig.js
@@ -2,12 +2,15 @@
  * @flow
  */
 
-'use strict';
+import type {
+  PlatformsT,
+  ContextT,
+  InquirerPromptT,
+  DependencyConfigT,
+} from '../core/types.flow';
 
 const path = require('path');
 
-import type { PlatformsT, ContextT, InquirerPromptT, DependencyConfigT } from '../core/types.flow';
-
 const getPackageConfiguration = require('../core/getPackageConfiguration');
 const getParams = require('../core/getParams');
 const getHooks = require('../core/getHooks');
@@ -32,13 +35,13 @@ module.exports = function getDependencyConfig(
       const folder = path.join(ctx.root, 'node_modules', packageName);
       const config = getPackageConfiguration(folder);
 
-      let platformConfigs = {ios: undefined, android: undefined};
+      const platformConfigs = { ios: undefined, android: undefined };
 
-      Object.keys(availablePlatforms)
-        .forEach(platform => {
-          platformConfigs[platform] = availablePlatforms[platform]
-            .dependencyConfig(folder, config[platform] || {});
-        });
+      Object.keys(availablePlatforms).forEach(platform => {
+        platformConfigs[platform] = availablePlatforms[
+          platform
+        ].dependencyConfig(folder, config[platform] || {});
+      });
 
       return acc.concat({
         config: platformConfigs,
@@ -46,7 +49,7 @@ module.exports = function getDependencyConfig(
         path: folder,
         commands: getHooks(folder),
         assets: getAssets(folder),
-        params: getParams(folder)
+        params: getParams(folder),
       });
     } catch (e) {
       return acc;
diff --git a/packages/local-cli/link/getProjectConfig.js b/packages/local-cli/link/getProjectConfig.js
index 690507cd7..905022193 100644
--- a/packages/local-cli/link/getProjectConfig.js
+++ b/packages/local-cli/link/getProjectConfig.js
@@ -2,8 +2,6 @@
  * @flow
  */
 
-'use strict';
-
 import type { PlatformsT, ContextT, ProjectConfigT } from '../core/types.flow';
 
 const getPackageConfiguration = require('../core/getPackageConfiguration');
@@ -13,16 +11,15 @@ module.exports = function getProjectConfig(
   availablePlatforms: PlatformsT
 ): ProjectConfigT {
   const config = getPackageConfiguration(ctx.root);
-  
-  let platformConfigs = {ios: undefined, android: undefined};
 
-  Object.keys(availablePlatforms)
-    .forEach(platform => {
-      platformConfigs[platform] = availablePlatforms[platform]
-        .projectConfig(ctx.root, config[platform] || {});
-    });
-  
+  const platformConfigs = { ios: undefined, android: undefined };
+
+  Object.keys(availablePlatforms).forEach(platform => {
+    platformConfigs[platform] = availablePlatforms[platform].projectConfig(
+      ctx.root,
+      config[platform] || {}
+    );
+  });
+
   return platformConfigs;
 };
-
- 
\ No newline at end of file
diff --git a/packages/local-cli/link/getProjectDependencies.js b/packages/local-cli/link/getProjectDependencies.js
index 94c0cf2c3..f72e6e5bc 100644
--- a/packages/local-cli/link/getProjectDependencies.js
+++ b/packages/local-cli/link/getProjectDependencies.js
@@ -10,11 +10,15 @@
 const path = require('path');
 
 /**
- * List of projects that should not be treated as projects to be linked. 
- * 
+ * List of projects that should not be treated as projects to be linked.
+ *
  * That includes `react-native` itself and the CLI project (under its real and staging npm package).
  */
-const EXCLUDED_PROJECTS = ['react-native', 'react-native-local-cli', 'react-native-local-cli-preview'];
+const EXCLUDED_PROJECTS = [
+  'react-native',
+  'react-native-local-cli',
+  'react-native-local-cli-preview',
+];
 
 /**
  * Returns an array of dependencies that should be linked/checked.
@@ -22,6 +26,6 @@ const EXCLUDED_PROJECTS = ['react-native', 'react-native-local-cli', 'react-nati
 module.exports = function getProjectDependencies(cwd) {
   const pjson = require(path.join(cwd || process.cwd(), './package.json'));
   return Object.keys(pjson.dependencies || {}).filter(
-    name => EXCLUDED_PROJECTS.includes(name) === false,
+    name => EXCLUDED_PROJECTS.includes(name) === false
   );
 };
diff --git a/packages/local-cli/link/groupFilesByType.js b/packages/local-cli/link/groupFilesByType.js
index d35e8e59e..54cb8ef5d 100644
--- a/packages/local-cli/link/groupFilesByType.js
+++ b/packages/local-cli/link/groupFilesByType.js
@@ -7,7 +7,7 @@
  * @format
  */
 
-const groupBy = require('lodash').groupBy;
+const { groupBy } = require('lodash');
 const mime = require('mime');
 
 /**
diff --git a/packages/local-cli/link/ios/addSharedLibraries.js b/packages/local-cli/link/ios/addSharedLibraries.js
index c8050689d..a97e3f69a 100644
--- a/packages/local-cli/link/ios/addSharedLibraries.js
+++ b/packages/local-cli/link/ios/addSharedLibraries.js
@@ -19,7 +19,7 @@ module.exports = function addSharedLibraries(project, libraries) {
 
   const target = project.getFirstTarget().uuid;
 
-  for (var name of libraries) {
-    project.addFramework(name, {target});
+  for (const name of libraries) {
+    project.addFramework(name, { target });
   }
 };
diff --git a/packages/local-cli/link/ios/common/registerNativeModule.js b/packages/local-cli/link/ios/common/registerNativeModule.js
index 8a86e6887..4b5d0ec86 100644
--- a/packages/local-cli/link/ios/common/registerNativeModule.js
+++ b/packages/local-cli/link/ios/common/registerNativeModule.js
@@ -14,7 +14,7 @@ module.exports = function registerNativeModule(
   name,
   dependencyConfig,
   params,
-  projectConfig,
+  projectConfig
 ) {
   if (projectConfig.podfile && dependencyConfig.podspec) {
     registerDependencyPods(name, dependencyConfig, projectConfig);
diff --git a/packages/local-cli/link/ios/common/unregisterNativeModule.js b/packages/local-cli/link/ios/common/unregisterNativeModule.js
index 69d25ea59..3cf4c718d 100644
--- a/packages/local-cli/link/ios/common/unregisterNativeModule.js
+++ b/packages/local-cli/link/ios/common/unregisterNativeModule.js
@@ -7,7 +7,7 @@
  * @format
  */
 
-const compact = require('lodash').compact;
+const { compact } = require('lodash');
 const isInstalledIOS = require('../isInstalled');
 const isInstalledPods = require('../../pods/isInstalled');
 const unregisterDependencyIOS = require('../unregisterNativeModule');
@@ -17,7 +17,7 @@ module.exports = function unregisterNativeModule(
   name,
   dependencyConfig,
   projectConfig,
-  otherDependencies,
+  otherDependencies
 ) {
   const isIosInstalled = isInstalledIOS(projectConfig, dependencyConfig);
   const isPodInstalled = isInstalledPods(projectConfig, dependencyConfig);
diff --git a/packages/local-cli/link/ios/copyAssets.js b/packages/local-cli/link/ios/copyAssets.js
index 314b68b60..cca28d8ac 100644
--- a/packages/local-cli/link/ios/copyAssets.js
+++ b/packages/local-cli/link/ios/copyAssets.js
@@ -31,7 +31,7 @@ module.exports = function linkAssetsIOS(files, projectConfig) {
       .map(asset =>
         project.addResourceFile(path.relative(projectConfig.sourceDir, asset), {
           target: project.getFirstTarget().uuid,
-        }),
+        })
       )
       .filter(file => file) // xcode returns false if file is already there
       .map(file => file.basename);
diff --git a/packages/local-cli/link/ios/createGroupWithMessage.js b/packages/local-cli/link/ios/createGroupWithMessage.js
index c353d9159..f89eb4299 100644
--- a/packages/local-cli/link/ios/createGroupWithMessage.js
+++ b/packages/local-cli/link/ios/createGroupWithMessage.js
@@ -19,14 +19,14 @@ const getGroup = require('./getGroup');
  * Returns the existing or newly created group
  */
 module.exports = function createGroupWithMessage(project, path) {
-  var group = getGroup(project, path);
+  let group = getGroup(project, path);
 
   if (!group) {
     group = createGroup(project, path);
 
     log.warn(
       'ERRGROUP',
-      `Group '${path}' does not exist in your Xcode project. We have created it automatically for you.`,
+      `Group '${path}' does not exist in your Xcode project. We have created it automatically for you.`
     );
   }
 
diff --git a/packages/local-cli/link/ios/getGroup.js b/packages/local-cli/link/ios/getGroup.js
index c53e731d9..0d1925c36 100644
--- a/packages/local-cli/link/ios/getGroup.js
+++ b/packages/local-cli/link/ios/getGroup.js
@@ -29,8 +29,8 @@ module.exports = function getGroup(project, path) {
     return groups;
   }
 
-  for (var name of path.split('/')) {
-    var foundGroup = findGroup(groups, name);
+  for (const name of path.split('/')) {
+    const foundGroup = findGroup(groups, name);
 
     if (foundGroup) {
       groups = project.getPBXGroupByKey(foundGroup.value);
diff --git a/packages/local-cli/link/ios/getHeaderSearchPath.js b/packages/local-cli/link/ios/getHeaderSearchPath.js
index bd1b5f5c5..323c4e439 100644
--- a/packages/local-cli/link/ios/getHeaderSearchPath.js
+++ b/packages/local-cli/link/ios/getHeaderSearchPath.js
@@ -8,8 +8,7 @@
  */
 
 const path = require('path');
-const union = require('lodash').union;
-const last = require('lodash').last;
+const { last, union } = require('lodash');
 
 /**
  * Given an array of directories, it returns the one that contains
@@ -57,6 +56,6 @@ module.exports = function getHeaderSearchPath(sourceDir, headers) {
     ? `"$(SRCROOT)${path.sep}${path.relative(sourceDir, directories[0])}"`
     : `"$(SRCROOT)${path.sep}${path.relative(
         sourceDir,
-        getOuterDirectory(directories),
+        getOuterDirectory(directories)
       )}/**"`;
 };
diff --git a/packages/local-cli/link/ios/getPlist.js b/packages/local-cli/link/ios/getPlist.js
index 61d0b5125..ee51c549b 100644
--- a/packages/local-cli/link/ios/getPlist.js
+++ b/packages/local-cli/link/ios/getPlist.js
@@ -8,8 +8,8 @@
  */
 
 const plistParser = require('plist');
-const getPlistPath = require('./getPlistPath');
 const fs = require('fs');
+const getPlistPath = require('./getPlistPath');
 
 /**
  * Returns Info.plist located in the iOS project
diff --git a/packages/local-cli/link/ios/getPlistPath.js b/packages/local-cli/link/ios/getPlistPath.js
index f8d570b9f..4fdbd0305 100644
--- a/packages/local-cli/link/ios/getPlistPath.js
+++ b/packages/local-cli/link/ios/getPlistPath.js
@@ -19,6 +19,6 @@ module.exports = function getPlistPath(project, sourceDir) {
 
   return path.join(
     sourceDir,
-    plistFile.replace(/"/g, '').replace('$(SRCROOT)', ''),
+    plistFile.replace(/"/g, '').replace('$(SRCROOT)', '')
   );
 };
diff --git a/packages/local-cli/link/ios/getTargets.js b/packages/local-cli/link/ios/getTargets.js
index 15f958598..17cdf9888 100644
--- a/packages/local-cli/link/ios/getTargets.js
+++ b/packages/local-cli/link/ios/getTargets.js
@@ -11,17 +11,19 @@
  * Given xcodeproj it returns list of targets
  */
 module.exports = function getTargets(project) {
-  let targets = project.getFirstProject().firstProject.targets;
-  let nativeTargetSection = project.pbxNativeTargetSection();
-  return targets.map(function(target) {
-    let key = target.value;
-    let configurationListId = project.pbxNativeTargetSection()[key]
+  const {
+    firstProject: { targets },
+  } = project.getFirstProject();
+  const nativeTargetSection = project.pbxNativeTargetSection();
+  return targets.map(target => {
+    const key = target.value;
+    const configurationListId = project.pbxNativeTargetSection()[key]
       .buildConfigurationList;
-    let configurationList = project.pbxXCConfigurationList()[
+    const configurationList = project.pbxXCConfigurationList()[
       configurationListId
     ];
-    let buildConfigurationId = configurationList.buildConfigurations[0].value;
-    let buildConfiguration = project.pbxXCBuildConfigurationSection()[
+    const buildConfigurationId = configurationList.buildConfigurations[0].value;
+    const buildConfiguration = project.pbxXCBuildConfigurationSection()[
       buildConfigurationId
     ];
     return {
diff --git a/packages/local-cli/link/ios/index.js b/packages/local-cli/link/ios/index.js
index aa31fd2ba..bff921b4b 100644
--- a/packages/local-cli/link/ios/index.js
+++ b/packages/local-cli/link/ios/index.js
@@ -7,7 +7,7 @@
  * @format
  */
 
-module.exports = function() {
+module.exports = function getIOSLinkConfig() {
   return {
     isInstalled: require('./common/isInstalled'),
     register: require('./common/registerNativeModule'),
diff --git a/packages/local-cli/link/ios/mapHeaderSearchPaths.js b/packages/local-cli/link/ios/mapHeaderSearchPaths.js
index 2754602d4..605241cce 100644
--- a/packages/local-cli/link/ios/mapHeaderSearchPaths.js
+++ b/packages/local-cli/link/ios/mapHeaderSearchPaths.js
@@ -30,7 +30,7 @@ module.exports = function headerSearchPathIter(project, func) {
   Object.keys(config)
     .filter(ref => ref.indexOf('_comment') === -1)
     .forEach(ref => {
-      const buildSettings = config[ref].buildSettings;
+      const { buildSettings } = config[ref];
       const shouldVisitBuildSettings =
         (Array.isArray(buildSettings.OTHER_LDFLAGS)
           ? buildSettings.OTHER_LDFLAGS
diff --git a/packages/local-cli/link/ios/registerNativeModule.js b/packages/local-cli/link/ios/registerNativeModule.js
index b68230ce3..cd2ba13ea 100644
--- a/packages/local-cli/link/ios/registerNativeModule.js
+++ b/packages/local-cli/link/ios/registerNativeModule.js
@@ -10,6 +10,7 @@
 const xcode = require('xcode');
 const fs = require('fs');
 const path = require('path');
+const { isEmpty } = require('lodash');
 
 const addToHeaderSearchPaths = require('./addToHeaderSearchPaths');
 const getHeadersInFolder = require('./getHeadersInFolder');
@@ -19,7 +20,6 @@ const createGroupWithMessage = require('./createGroupWithMessage');
 const addFileToProject = require('./addFileToProject');
 const addProjectToLibraries = require('./addProjectToLibraries');
 const addSharedLibraries = require('./addSharedLibraries');
-const isEmpty = require('lodash').isEmpty;
 
 /**
  * Register native module IOS adds given dependency to project by adding
@@ -30,7 +30,7 @@ const isEmpty = require('lodash').isEmpty;
  */
 module.exports = function registerNativeModuleIOS(
   dependencyConfig,
-  projectConfig,
+  projectConfig
 ) {
   const project = xcode.project(projectConfig.pbxprojPath).parseSync();
   const dependencyProject = xcode
@@ -39,11 +39,11 @@ module.exports = function registerNativeModuleIOS(
 
   const libraries = createGroupWithMessage(
     project,
-    projectConfig.libraryFolder,
+    projectConfig.libraryFolder
   );
   const file = addFileToProject(
     project,
-    path.relative(projectConfig.sourceDir, dependencyConfig.projectPath),
+    path.relative(projectConfig.sourceDir, dependencyConfig.projectPath)
   );
 
   const targets = getTargets(project);
@@ -51,7 +51,7 @@ module.exports = function registerNativeModuleIOS(
   addProjectToLibraries(libraries, file);
 
   getTargets(dependencyProject).forEach(product => {
-    var i;
+    let i;
     if (!product.isTVOS) {
       for (i = 0; i < targets.length; i++) {
         if (!targets[i].isTVOS) {
@@ -79,7 +79,7 @@ module.exports = function registerNativeModuleIOS(
   if (!isEmpty(headers)) {
     addToHeaderSearchPaths(
       project,
-      getHeaderSearchPath(projectConfig.sourceDir, headers),
+      getHeaderSearchPath(projectConfig.sourceDir, headers)
     );
   }
 
diff --git a/packages/local-cli/link/ios/removeFromHeaderSearchPaths.js b/packages/local-cli/link/ios/removeFromHeaderSearchPaths.js
index e7fc30fa1..10c6b3cfd 100644
--- a/packages/local-cli/link/ios/removeFromHeaderSearchPaths.js
+++ b/packages/local-cli/link/ios/removeFromHeaderSearchPaths.js
@@ -14,6 +14,6 @@ const mapHeaderSearchPaths = require('./mapHeaderSearchPaths');
  */
 module.exports = function addToHeaderSearchPaths(project, path) {
   mapHeaderSearchPaths(project, searchPaths =>
-    searchPaths.filter(searchPath => searchPath !== path),
+    searchPaths.filter(searchPath => searchPath !== path)
   );
 };
diff --git a/packages/local-cli/link/ios/removeFromPbxItemContainerProxySection.js b/packages/local-cli/link/ios/removeFromPbxItemContainerProxySection.js
index b2277ce88..4cdc8a0c4 100644
--- a/packages/local-cli/link/ios/removeFromPbxItemContainerProxySection.js
+++ b/packages/local-cli/link/ios/removeFromPbxItemContainerProxySection.js
@@ -14,15 +14,13 @@
  */
 module.exports = function removeFromPbxItemContainerProxySection(
   project,
-  file,
+  file
 ) {
   const section = project.hash.project.objects.PBXContainerItemProxy;
 
-  for (var key of Object.keys(section)) {
+  for (const key of Object.keys(section)) {
     if (section[key].containerPortal === file.uuid) {
       delete section[key];
     }
   }
-
-  return;
 };
diff --git a/packages/local-cli/link/ios/removeFromPbxReferenceProxySection.js b/packages/local-cli/link/ios/removeFromPbxReferenceProxySection.js
index 52f8056a5..e565e37a0 100644
--- a/packages/local-cli/link/ios/removeFromPbxReferenceProxySection.js
+++ b/packages/local-cli/link/ios/removeFromPbxReferenceProxySection.js
@@ -14,11 +14,9 @@
 module.exports = function removeFromPbxReferenceProxySection(project, file) {
   const section = project.hash.project.objects.PBXReferenceProxy;
 
-  for (var key of Object.keys(section)) {
+  for (const key of Object.keys(section)) {
     if (section[key].path === file.basename) {
       delete section[key];
     }
   }
-
-  return;
 };
diff --git a/packages/local-cli/link/ios/removeFromProjectReferences.js b/packages/local-cli/link/ios/removeFromProjectReferences.js
index 8a776bf72..2e532b5d0 100644
--- a/packages/local-cli/link/ios/removeFromProjectReferences.js
+++ b/packages/local-cli/link/ios/removeFromProjectReferences.js
@@ -18,10 +18,10 @@
  * Otherwise returns null
  */
 module.exports = function removeFromProjectReferences(project, file) {
-  const firstProject = project.getFirstProject().firstProject;
+  const { firstProject } = project.getFirstProject();
 
   const projectRef = firstProject.projectReferences.find(
-    item => item.ProjectRef === file.uuid,
+    item => item.ProjectRef === file.uuid
   );
 
   if (!projectRef) {
@@ -30,7 +30,7 @@ module.exports = function removeFromProjectReferences(project, file) {
 
   firstProject.projectReferences.splice(
     firstProject.projectReferences.indexOf(projectRef),
-    1,
+    1
   );
 
   return projectRef;
diff --git a/packages/local-cli/link/ios/removeProductGroup.js b/packages/local-cli/link/ios/removeProductGroup.js
index f012ff25c..b491415e7 100644
--- a/packages/local-cli/link/ios/removeProductGroup.js
+++ b/packages/local-cli/link/ios/removeProductGroup.js
@@ -10,11 +10,9 @@
 module.exports = function removeProductGroup(project, productGroupId) {
   const section = project.hash.project.objects.PBXGroup;
 
-  for (var key of Object.keys(section)) {
+  for (const key of Object.keys(section)) {
     if (key === productGroupId) {
       delete section[key];
     }
   }
-
-  return;
 };
diff --git a/packages/local-cli/link/ios/removeProjectFromLibraries.js b/packages/local-cli/link/ios/removeProjectFromLibraries.js
index 0402d777a..e049584e5 100644
--- a/packages/local-cli/link/ios/removeProjectFromLibraries.js
+++ b/packages/local-cli/link/ios/removeProjectFromLibraries.js
@@ -3,8 +3,6 @@
  *
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
- *
- * @format
  */
 
 /**
@@ -15,7 +13,8 @@
  * It's mainly due to limitations of `xcode` library.
  */
 module.exports = function removeProjectFromLibraries(libraries, file) {
+  // eslint-disable-next-line no-param-reassign
   libraries.children = libraries.children.filter(
-    library => library.comment !== file.basename,
+    library => library.comment !== file.basename
   );
 };
diff --git a/packages/local-cli/link/ios/removeSharedLibraries.js b/packages/local-cli/link/ios/removeSharedLibraries.js
index 1a34b7c1a..825aa632f 100644
--- a/packages/local-cli/link/ios/removeSharedLibraries.js
+++ b/packages/local-cli/link/ios/removeSharedLibraries.js
@@ -14,7 +14,7 @@ module.exports = function removeSharedLibraries(project, libraries) {
 
   const target = project.getFirstTarget().uuid;
 
-  for (var name of libraries) {
-    project.removeFramework(name, {target});
+  for (const name of libraries) {
+    project.removeFramework(name, { target });
   }
 };
diff --git a/packages/local-cli/link/ios/unlinkAssets.js b/packages/local-cli/link/ios/unlinkAssets.js
index 1df299fdd..55dbbe875 100644
--- a/packages/local-cli/link/ios/unlinkAssets.js
+++ b/packages/local-cli/link/ios/unlinkAssets.js
@@ -4,17 +4,18 @@
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
  *
- * @format
+ * @flow
  */
 
 const fs = require('fs-extra');
 const path = require('path');
 const xcode = require('xcode');
 const log = require('npmlog');
+const { difference } = require('lodash');
+
 const groupFilesByType = require('../groupFilesByType');
 const getPlist = require('./getPlist');
 const writePlist = require('./writePlist');
-const difference = require('lodash').difference;
 
 /**
  * Unlinks assets from iOS project. Removes references for fonts from `Info.plist`
@@ -26,33 +27,34 @@ module.exports = function unlinkAssetsIOS(files, projectConfig) {
   const plist = getPlist(project, projectConfig.sourceDir);
 
   if (!plist) {
-    return log.error(
+    log.error(
       'ERRPLIST',
-      "Could not locate Info.plist file. Check if your project has 'INFOPLIST_FILE' set properly",
+      "Could not locate Info.plist file. Check if your project has 'INFOPLIST_FILE' set properly"
     );
+    return;
   }
 
   if (!project.pbxGroupByName('Resources')) {
-    return log.error(
+    log.error(
       'ERRGROUP',
-      "Group 'Resources' does not exist in your Xcode project. There is nothing to unlink.",
+      "Group 'Resources' does not exist in your Xcode project. There is nothing to unlink."
     );
+    return;
   }
 
-  const removeResourceFile = function(f) {
+  const removeResourceFiles = (f: string[] = []) =>
     (f || [])
       .map(asset =>
         project.removeResourceFile(
           path.relative(projectConfig.sourceDir, asset),
-          {target: project.getFirstTarget().uuid},
-        ),
+          { target: project.getFirstTarget().uuid }
+        )
       )
       .map(file => file.basename);
-  };
 
-  removeResourceFile(assets.image);
+  removeResourceFiles(assets.image);
 
-  const fonts = removeResourceFile(assets.font);
+  const fonts = removeResourceFiles(assets.font);
 
   plist.UIAppFonts = difference(plist.UIAppFonts || [], fonts);
 
diff --git a/packages/local-cli/link/ios/unregisterNativeModule.js b/packages/local-cli/link/ios/unregisterNativeModule.js
index c9b83a880..71b1f2ced 100644
--- a/packages/local-cli/link/ios/unregisterNativeModule.js
+++ b/packages/local-cli/link/ios/unregisterNativeModule.js
@@ -10,8 +10,7 @@
 const xcode = require('xcode');
 const path = require('path');
 const fs = require('fs');
-const difference = require('lodash').difference;
-const isEmpty = require('lodash').isEmpty;
+const { difference, isEmpty } = require('lodash');
 
 const getGroup = require('./getGroup');
 const getTargets = require('./getTargets');
@@ -31,7 +30,7 @@ const removeSharedLibraries = require('./removeSharedLibraries');
 module.exports = function unregisterNativeModule(
   dependencyConfig,
   projectConfig,
-  iOSDependencies,
+  iOSDependencies
 ) {
   const project = xcode.project(projectConfig.pbxprojPath).parseSync();
   const dependencyProject = xcode
@@ -42,7 +41,7 @@ module.exports = function unregisterNativeModule(
 
   const file = removeProjectFromProject(
     project,
-    path.relative(projectConfig.sourceDir, dependencyConfig.projectPath),
+    path.relative(projectConfig.sourceDir, dependencyConfig.projectPath)
   );
 
   removeProjectFromLibraries(libraries, file);
@@ -57,8 +56,8 @@ module.exports = function unregisterNativeModule(
     dependencyConfig.sharedLibraries,
     iOSDependencies.reduce(
       (libs, dependency) => libs.concat(dependency.sharedLibraries),
-      projectConfig.sharedLibraries,
-    ),
+      projectConfig.sharedLibraries
+    )
   );
 
   removeSharedLibraries(project, sharedLibraries);
@@ -67,7 +66,7 @@ module.exports = function unregisterNativeModule(
   if (!isEmpty(headers)) {
     removeFromHeaderSearchPaths(
       project,
-      getHeaderSearchPath(projectConfig.sourceDir, headers),
+      getHeaderSearchPath(projectConfig.sourceDir, headers)
     );
   }
 
diff --git a/packages/local-cli/link/ios/writePlist.js b/packages/local-cli/link/ios/writePlist.js
index 009de34e2..a0477bd48 100644
--- a/packages/local-cli/link/ios/writePlist.js
+++ b/packages/local-cli/link/ios/writePlist.js
@@ -8,8 +8,8 @@
  */
 
 const plistParser = require('plist');
-const getPlistPath = require('./getPlistPath');
 const fs = require('fs');
+const getPlistPath = require('./getPlistPath');
 
 /**
  * Writes to Info.plist located in the iOS project
@@ -28,6 +28,6 @@ module.exports = function writePlist(project, sourceDir, plist) {
   // Ref: https://github.com/facebook/react-native/issues/11668
   return fs.writeFileSync(
     plistPath,
-    plistParser.build(plist, {indent: '\t', offset: -1}) + '\n',
+    `${plistParser.build(plist, { indent: '\t', offset: -1 })}\n`
   );
 };
diff --git a/packages/local-cli/link/link.js b/packages/local-cli/link/link.js
index 4e9aaf6ed..501bacb1b 100644
--- a/packages/local-cli/link/link.js
+++ b/packages/local-cli/link/link.js
@@ -8,12 +8,12 @@
  * @flow
  */
 
+import type { ContextT } from '../core/types.flow';
+
 const log = require('npmlog');
 const path = require('path');
-const uniqBy = require('lodash').uniqBy;
-const flatten = require('lodash').flatten;
+const { flatten, isEmpty, uniqBy } = require('lodash');
 const chalk = require('chalk');
-const isEmpty = require('lodash').isEmpty;
 const promiseWaterfall = require('./promiseWaterfall');
 const getProjectDependencies = require('./getProjectDependencies');
 const getDependencyConfig = require('./getDependencyConfig');
@@ -24,13 +24,9 @@ const getProjectConfig = require('./getProjectConfig');
 
 const findReactNativeScripts = require('../util/findReactNativeScripts');
 
-const getHooks = require('../core/getHooks');
-const getParams = require('../core/getParams');
 const getAssets = require('../core/getAssets');
 const getPlatforms = require('../core/getPlatforms');
 
-import type {ContextT} from '../core/types.flow';
-
 log.heading = 'rnpm-link';
 
 const dedupeAssets = assets => uniqBy(assets, asset => path.basename(asset));
@@ -40,7 +36,7 @@ const linkDependency = async (platforms, project, dependency) => {
 
   Object.keys(platforms || {}).forEach(platform => {
     if (!project[platform] || !dependency.config[platform]) {
-      return null;
+      return;
     }
 
     const linkConfig =
@@ -48,22 +44,22 @@ const linkDependency = async (platforms, project, dependency) => {
       platforms[platform].linkConfig &&
       platforms[platform].linkConfig();
     if (!linkConfig || !linkConfig.isInstalled || !linkConfig.register) {
-      return null;
+      return;
     }
 
     const isInstalled = linkConfig.isInstalled(
       project[platform],
       dependency.name,
-      dependency.config[platform],
+      dependency.config[platform]
     );
 
     if (isInstalled) {
       log.info(
         chalk.grey(
-          `Platform '${platform}' module ${dependency.name} is already linked`,
-        ),
+          `Platform '${platform}' module ${dependency.name} is already linked`
+        )
       );
-      return null;
+      return;
     }
 
     log.info(`Linking ${dependency.name} ${platform} dependency`);
@@ -74,13 +70,13 @@ const linkDependency = async (platforms, project, dependency) => {
       dependency.config[platform],
       params,
       // $FlowFixMe: We check if project[platform] exists on line 42
-      project[platform],
+      project[platform]
     );
 
     log.info(
       `Platform '${platform}' module ${
         dependency.name
-      } has been successfully linked`,
+      } has been successfully linked`
     );
   });
 };
@@ -95,11 +91,11 @@ const linkAssets = (platforms, project, assets) => {
       platforms[platform] &&
       platforms[platform].linkConfig &&
       platforms[platform].linkConfig();
-    
+
     if (!linkConfig || !linkConfig.copyAssets || !project[platform]) {
       return;
     }
-    
+
     log.info(`Linking assets to ${platform} project`);
     // $FlowFixMe: We check for existence of project[platform] on line 97.
     linkConfig.copyAssets(assets, project[platform]);
@@ -123,13 +119,13 @@ function link(args: Array<string>, ctx: ContextT) {
   } catch (err) {
     log.error(
       'ERRPACKAGEJSON',
-      'No package found. Are you sure this is a React Native project?',
+      'No package found. Are you sure this is a React Native project?'
     );
     return Promise.reject(err);
   }
   const hasProjectConfig = Object.keys(platforms).reduce(
     (acc, key) => acc || key in project,
-    false,
+    false
   );
   if (!hasProjectConfig && findReactNativeScripts()) {
     throw new Error(
@@ -137,7 +133,7 @@ function link(args: Array<string>, ctx: ContextT) {
         'If you need to include a library that relies on custom native code, ' +
         'you might have to eject first. ' +
         'See https://github.com/react-community/create-react-native-app/blob/master/EJECTING.md ' +
-        'for more information.',
+        'for more information.'
     );
   }
 
@@ -154,14 +150,14 @@ function link(args: Array<string>, ctx: ContextT) {
   const dependencies = getDependencyConfig(
     ctx,
     platforms,
-    packageName ? [packageName] : getProjectDependencies(ctx.root),
+    packageName ? [packageName] : getProjectDependencies(ctx.root)
   );
 
   const assets = dedupeAssets(
     dependencies.reduce(
       (acc, dependency) => acc.concat(dependency.assets),
-      getAssets(ctx.root),
-    ),
+      getAssets(ctx.root)
+    )
   );
 
   const tasks = flatten(
@@ -169,7 +165,7 @@ function link(args: Array<string>, ctx: ContextT) {
       () => promisify(dependency.commands.prelink || commandStub),
       () => linkDependency(platforms, project, dependency),
       () => promisify(dependency.commands.postlink || commandStub),
-    ]),
+    ])
   );
 
   tasks.push(() => linkAssets(platforms, project, assets));
@@ -177,7 +173,7 @@ function link(args: Array<string>, ctx: ContextT) {
   return promiseWaterfall(tasks).catch(err => {
     log.error(
       `Something went wrong while linking. Error: ${err.message} \n` +
-        'Please file an issue here: https://github.com/facebook/react-native/issues',
+        'Please file an issue here: https://github.com/facebook/react-native/issues'
     );
     throw err;
   });
diff --git a/packages/local-cli/link/pods/addPodEntry.js b/packages/local-cli/link/pods/addPodEntry.js
index e89716eb6..b535d3477 100644
--- a/packages/local-cli/link/pods/addPodEntry.js
+++ b/packages/local-cli/link/pods/addPodEntry.js
@@ -7,24 +7,24 @@
  * @format
  */
 
-'use strict';
-
 module.exports = function addPodEntry(
   podLines,
   linesToAddEntry,
   podName,
-  nodePath,
+  nodePath
 ) {
   const newEntry = `pod '${podName}', :path => '../node_modules/${nodePath}'\n`;
 
   if (!linesToAddEntry) {
     return;
-  } else if (Array.isArray(linesToAddEntry)) {
-    linesToAddEntry.map(({line, indentation}, idx) =>
-      podLines.splice(line + idx, 0, getLineToAdd(newEntry, indentation)),
+  }
+
+  if (Array.isArray(linesToAddEntry)) {
+    linesToAddEntry.map(({ line, indentation }, idx) =>
+      podLines.splice(line + idx, 0, getLineToAdd(newEntry, indentation))
     );
   } else {
-    const {line, indentation} = linesToAddEntry;
+    const { line, indentation } = linesToAddEntry;
     podLines.splice(line, 0, getLineToAdd(newEntry, indentation));
   }
 };
diff --git a/packages/local-cli/link/pods/findLineToAddPod.js b/packages/local-cli/link/pods/findLineToAddPod.js
index d6902838e..2a38e0464 100644
--- a/packages/local-cli/link/pods/findLineToAddPod.js
+++ b/packages/local-cli/link/pods/findLineToAddPod.js
@@ -7,11 +7,9 @@
  * @format
  */
 
-'use strict';
-
 module.exports = function findLineToAddPod(podLines, firstTargetLine) {
   // match line with new target: target 'project_name' do (most likely target inside podfile main target)
-  const nextTarget = /target (\'|\")\w+(\'|\") do/g;
+  const nextTarget = /target ('|")\w+('|") do/g;
   // match line that has only 'end' (if we don't catch new target or function, this would mean this is end of current target)
   const endOfCurrentTarget = /^\s*end\s*$/g;
   // match function definition, like: post_install do |installer| (some Podfiles have function defined inside main target
diff --git a/packages/local-cli/link/pods/findMarkedLinesInPodfile.js b/packages/local-cli/link/pods/findMarkedLinesInPodfile.js
index 5df1c33ac..43710ab27 100644
--- a/packages/local-cli/link/pods/findMarkedLinesInPodfile.js
+++ b/packages/local-cli/link/pods/findMarkedLinesInPodfile.js
@@ -7,14 +7,13 @@
  * @format
  */
 
-'use strict';
 const MARKER_TEXT = '# Add new pods below this line';
 
 module.exports = function findMarkedLinesInPodfile(podLines) {
   const result = [];
   for (let i = 0, len = podLines.length; i < len; i++) {
     if (podLines[i].includes(MARKER_TEXT)) {
-      result.push({line: i + 1, indentation: podLines[i].indexOf('#')});
+      result.push({ line: i + 1, indentation: podLines[i].indexOf('#') });
     }
   }
   return result;
diff --git a/packages/local-cli/link/pods/findPodTargetLine.js b/packages/local-cli/link/pods/findPodTargetLine.js
index 22070f8dd..5d34ae804 100644
--- a/packages/local-cli/link/pods/findPodTargetLine.js
+++ b/packages/local-cli/link/pods/findPodTargetLine.js
@@ -7,15 +7,10 @@
  * @format
  */
 
-'use strict';
-
 module.exports = function findPodTargetLine(podLines, projectName) {
   const targetName = projectName.replace('.xcodeproj', '');
-  //match first target definition in file: target 'target_name' do
-  const targetRegex = new RegExp(
-    'target (\'|")' + targetName + '(\'|") do',
-    'g',
-  );
+  // match first target definition in file: target 'target_name' do
+  const targetRegex = new RegExp(`target ('|")${targetName}('|") do`, 'g');
   for (let i = 0, len = podLines.length; i < len; i++) {
     const match = podLines[i].match(targetRegex);
     if (match) {
diff --git a/packages/local-cli/link/pods/isInstalled.js b/packages/local-cli/link/pods/isInstalled.js
index d7602d14d..35e484c70 100644
--- a/packages/local-cli/link/pods/isInstalled.js
+++ b/packages/local-cli/link/pods/isInstalled.js
@@ -7,8 +7,6 @@
  * @format
  */
 
-'use strict';
-
 const readPodfile = require('./readPodfile');
 
 module.exports = function isInstalled(iOSProject, dependencyConfig) {
@@ -17,8 +15,8 @@ module.exports = function isInstalled(iOSProject, dependencyConfig) {
   }
   // match line with pod declaration: pod 'dependencyPodName' (other possible parameters of pod are ignored)
   const dependencyRegExp = new RegExp(
-    'pod\\s+(\'|")' + dependencyConfig.podspec + '(\'|")',
-    'g',
+    `pod\\s+('|")${dependencyConfig.podspec}('|")`,
+    'g'
   );
   const podLines = readPodfile(iOSProject.podfile);
   for (let i = 0, len = podLines.length; i < len; i++) {
diff --git a/packages/local-cli/link/pods/readPodfile.js b/packages/local-cli/link/pods/readPodfile.js
index 281a0a0e4..0e86affa2 100644
--- a/packages/local-cli/link/pods/readPodfile.js
+++ b/packages/local-cli/link/pods/readPodfile.js
@@ -7,8 +7,6 @@
  * @format
  */
 
-'use strict';
-
 const fs = require('fs');
 
 module.exports = function readPodfile(podfilePath) {
diff --git a/packages/local-cli/link/pods/registerNativeModule.js b/packages/local-cli/link/pods/registerNativeModule.js
index f8e757b27..b8d96517e 100644
--- a/packages/local-cli/link/pods/registerNativeModule.js
+++ b/packages/local-cli/link/pods/registerNativeModule.js
@@ -7,8 +7,6 @@
  * @format
  */
 
-'use strict';
-
 const readPodfile = require('./readPodfile');
 const findPodTargetLine = require('./findPodTargetLine');
 const findLineToAddPod = require('./findLineToAddPod');
@@ -19,7 +17,7 @@ const savePodFile = require('./savePodFile');
 module.exports = function registerNativeModulePods(
   name,
   dependencyConfig,
-  iOSProject,
+  iOSProject
 ) {
   const podLines = readPodfile(iOSProject.podfile);
   const linesToAddEntry = getLinesToAddEntry(podLines, iOSProject);
@@ -27,12 +25,11 @@ module.exports = function registerNativeModulePods(
   savePodFile(iOSProject.podfile, podLines);
 };
 
-function getLinesToAddEntry(podLines, {projectName}) {
+function getLinesToAddEntry(podLines, { projectName }) {
   const linesToAddPodWithMarker = findMarkedLinesInPodfile(podLines);
   if (linesToAddPodWithMarker.length > 0) {
     return linesToAddPodWithMarker;
-  } else {
-    const firstTargetLined = findPodTargetLine(podLines, projectName);
-    return findLineToAddPod(podLines, firstTargetLined);
   }
+  const firstTargetLined = findPodTargetLine(podLines, projectName);
+  return findLineToAddPod(podLines, firstTargetLined);
 }
diff --git a/packages/local-cli/link/pods/removePodEntry.js b/packages/local-cli/link/pods/removePodEntry.js
index 02ef4746f..006394320 100644
--- a/packages/local-cli/link/pods/removePodEntry.js
+++ b/packages/local-cli/link/pods/removePodEntry.js
@@ -7,15 +7,11 @@
  * @format
  */
 
-'use strict';
-
 module.exports = function removePodEntry(podfileContent, podName) {
   // this regex should catch line(s) with full pod definition, like: pod 'podname', :path => '../node_modules/podname', :subspecs => ['Sub2', 'Sub1']
   const podRegex = new RegExp(
-    '\\n( |\\t)*pod\\s+("|\')' +
-      podName +
-      '("|\')(,\\s*(:[a-z]+\\s*=>)?\\s*(("|\').*?("|\')|\\[[\\s\\S]*?\\]))*\\n',
-    'g',
+    `\\n( |\\t)*pod\\s+("|')${podName}("|')(,\\s*(:[a-z]+\\s*=>)?\\s*(("|').*?("|')|\\[[\\s\\S]*?\\]))*\\n`,
+    'g'
   );
   return podfileContent.replace(podRegex, '\n');
 };
diff --git a/packages/local-cli/link/pods/savePodFile.js b/packages/local-cli/link/pods/savePodFile.js
index 640bb646f..adb3baf53 100644
--- a/packages/local-cli/link/pods/savePodFile.js
+++ b/packages/local-cli/link/pods/savePodFile.js
@@ -7,8 +7,6 @@
  * @format
  */
 
-'use strict';
-
 const fs = require('fs');
 
 module.exports = function savePodFile(podfilePath, podLines) {
diff --git a/packages/local-cli/link/pods/unregisterNativeModule.js b/packages/local-cli/link/pods/unregisterNativeModule.js
index 048e3e8de..235dd11c7 100644
--- a/packages/local-cli/link/pods/unregisterNativeModule.js
+++ b/packages/local-cli/link/pods/unregisterNativeModule.js
@@ -7,8 +7,6 @@
  * @format
  */
 
-'use strict';
-
 const fs = require('fs');
 const removePodEntry = require('./removePodEntry');
 
diff --git a/packages/local-cli/link/pollParams.js b/packages/local-cli/link/pollParams.js
index 6cf23020d..039160c33 100644
--- a/packages/local-cli/link/pollParams.js
+++ b/packages/local-cli/link/pollParams.js
@@ -7,12 +7,13 @@
  * @format
  */
 
-var inquirer = require('inquirer');
+const inquirer = require('inquirer');
 
 module.exports = questions =>
   new Promise((resolve, reject) => {
     if (!questions) {
-      return resolve({});
+      resolve({});
+      return;
     }
 
     inquirer.prompt(questions).then(resolve, reject);
diff --git a/packages/local-cli/link/promiseWaterfall.js b/packages/local-cli/link/promiseWaterfall.js
index 0a2ddac88..b0f77e3b2 100644
--- a/packages/local-cli/link/promiseWaterfall.js
+++ b/packages/local-cli/link/promiseWaterfall.js
@@ -18,6 +18,6 @@
 module.exports = function promiseWaterfall(tasks) {
   return tasks.reduce(
     (prevTaskPromise, task) => prevTaskPromise.then(task),
-    Promise.resolve(),
+    Promise.resolve()
   );
 };
diff --git a/packages/local-cli/link/promisify.js b/packages/local-cli/link/promisify.js
index 2605bf95e..3afb6870a 100644
--- a/packages/local-cli/link/promisify.js
+++ b/packages/local-cli/link/promisify.js
@@ -9,5 +9,5 @@
 
 module.exports = func =>
   new Promise((resolve, reject) =>
-    func((err, res) => (err ? reject(err) : resolve(res))),
+    func((err, res) => (err ? reject(err) : resolve(res)))
   );
diff --git a/packages/local-cli/link/unlink.js b/packages/local-cli/link/unlink.js
index fd8199fb4..b3cb03270 100644
--- a/packages/local-cli/link/unlink.js
+++ b/packages/local-cli/link/unlink.js
@@ -7,24 +7,20 @@
  * @flow
  */
 
+import type { ContextT } from '../core/types.flow';
+
 const log = require('npmlog');
 
-const getProjectDependencies = require('./getProjectDependencies');
-const getDependencyConfig = require('./getDependencyConfig');
+const { flatten, isEmpty, difference } = require('lodash');
 const getProjectConfig = require('./getProjectConfig');
-
-const difference = require('lodash').difference;
-const filter = require('lodash').filter;
-const flatten = require('lodash').flatten;
-const isEmpty = require('lodash').isEmpty;
+const getDependencyConfig = require('./getDependencyConfig');
+const getProjectDependencies = require('./getProjectDependencies');
 const promiseWaterfall = require('./promiseWaterfall');
 const commandStub = require('./commandStub');
 const promisify = require('./promisify');
 
 const getPlatforms = require('../core/getPlatforms');
 
-import type { ContextT } from '../core/types.flow';
-
 log.heading = 'rnpm-link';
 
 const unlinkDependency = (
@@ -32,7 +28,7 @@ const unlinkDependency = (
   project,
   dependency,
   packageName,
-  otherDependencies,
+  otherDependencies
 ) => {
   Object.keys(platforms || {}).forEach(platform => {
     if (!project[platform] || !dependency.config[platform]) {
@@ -50,7 +46,7 @@ const unlinkDependency = (
     const isInstalled = linkConfig.isInstalled(
       project[platform],
       packageName,
-      dependency.config[platform],
+      dependency.config[platform]
     );
 
     if (!isInstalled) {
@@ -66,13 +62,13 @@ const unlinkDependency = (
       dependency.config[platform],
       // $FlowFixMe: We check for existence on line 38
       project[platform],
-      otherDependencies,
+      otherDependencies
     );
 
     log.info(
       `Platform '${platform}' module ${
         dependency.name
-      } has been successfully unlinked`,
+      } has been successfully unlinked`
     );
   });
 };
@@ -93,12 +89,16 @@ function unlink(args: Array<string>, ctx: ContextT) {
   } catch (err) {
     log.error(
       'ERRPACKAGEJSON',
-      "No package found. Are you sure it's a React Native project?",
+      "No package found. Are you sure it's a React Native project?"
     );
     return Promise.reject(err);
   }
 
-  const allDependencies = getDependencyConfig(ctx, platforms, getProjectDependencies());
+  const allDependencies = getDependencyConfig(
+    ctx,
+    platforms,
+    getProjectDependencies()
+  );
   let otherDependencies;
   let dependency;
 
@@ -110,7 +110,7 @@ function unlink(args: Array<string>, ctx: ContextT) {
     }
 
     otherDependencies = [...allDependencies];
-    dependency = otherDependencies.splice(idx, 1)[0];
+    dependency = otherDependencies.splice(idx, 1)[0]; // eslint-disable-line prefer-destructuring
   } catch (err) {
     log.warn('ERRINVALIDPROJ', err.message);
     return Promise.reject(err);
@@ -126,7 +126,7 @@ function unlink(args: Array<string>, ctx: ContextT) {
         project,
         dependency,
         packageName,
-        otherDependencies,
+        otherDependencies
       ),
     () => promisify(dependency.commands.postunlink || commandStub),
   ];
@@ -137,11 +137,11 @@ function unlink(args: Array<string>, ctx: ContextT) {
       // link
       const assets = difference(
         dependency.assets,
-        flatten(allDependencies, d => d.assets),
+        flatten(allDependencies, d => d.assets)
       );
 
       if (isEmpty(assets)) {
-        return Promise.resolve();
+        return;
       }
 
       Object.keys(platforms || {}).forEach(platform => {
@@ -159,12 +159,12 @@ function unlink(args: Array<string>, ctx: ContextT) {
       });
 
       log.info(
-        `${packageName} assets has been successfully unlinked from your project`,
+        `${packageName} assets has been successfully unlinked from your project`
       );
     })
     .catch(err => {
       log.error(
-        `It seems something went wrong while unlinking. Error: ${err.message}`,
+        `It seems something went wrong while unlinking. Error: ${err.message}`
       );
       throw err;
     });
diff --git a/packages/local-cli/logAndroid/logAndroid.js b/packages/local-cli/logAndroid/logAndroid.js
index 322bc8eae..fc57e4e5e 100644
--- a/packages/local-cli/logAndroid/logAndroid.js
+++ b/packages/local-cli/logAndroid/logAndroid.js
@@ -3,46 +3,29 @@
  *
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
- *
- * @format
  */
 
-'use strict';
-
 const chalk = require('chalk');
-const child_process = require('child_process');
+const { spawnSync } = require('child_process');
 
 /**
  * Starts adb logcat
  */
-function logAndroid() {
-  return new Promise((resolve, reject) => {
-    _logAndroid(resolve, reject);
-  });
-}
-
-function _logAndroid() {
-  try {
-    const adbPath = process.env.ANDROID_HOME
-      ? process.env.ANDROID_HOME + '/platform-tools/adb'
-      : 'adb';
+async function logAndroid() {
+  const adbPath = process.env.ANDROID_HOME
+    ? `${process.env.ANDROID_HOME}/platform-tools/adb`
+    : 'adb';
 
-    const adbArgs = ['logcat', '*:S', 'ReactNative:V', 'ReactNativeJS:V'];
+  const adbArgs = ['logcat', '*:S', 'ReactNative:V', 'ReactNativeJS:V'];
 
-    console.log(
-      chalk.bold(`Starting the logger (${adbPath} ${adbArgs.join(' ')})...`),
-    );
+  console.log(
+    chalk.bold(`Starting the logger (${adbPath} ${adbArgs.join(' ')})...`)
+  );
 
-    const log = child_process.spawnSync(adbPath, adbArgs, {stdio: 'inherit'});
+  const log = spawnSync(adbPath, adbArgs, { stdio: 'inherit' });
 
-    if (log.error !== null) {
-      throw log.error;
-    }
-  } catch (e) {
-    console.log(
-      chalk.red('adb invocation failed. Do you have adb in your PATH?'),
-    );
-    return Promise.reject();
+  if (log.error !== null) {
+    throw log.error;
   }
 }
 
diff --git a/packages/local-cli/logIOS/logIOS.js b/packages/local-cli/logIOS/logIOS.js
index 9d9aa68fa..641dbe157 100644
--- a/packages/local-cli/logIOS/logIOS.js
+++ b/packages/local-cli/logIOS/logIOS.js
@@ -7,59 +7,41 @@
  * @format
  */
 
-'use strict';
-
 const chalk = require('chalk');
-const child_process = require('child_process');
+const { execFileSync, spawnSync } = require('child_process');
 const os = require('os');
 const path = require('path');
 
+function findAvailableDevice(devices) {
+  for (const key of Object.keys(devices)) {
+    for (const device of devices[key]) {
+      if (device.availability === '(available)' && device.state === 'Booted') {
+        return device;
+      }
+    }
+  }
+  return null;
+}
+
 /**
  * Starts iOS device syslog tail
  */
-function logIOS() {
-  return new Promise((resolve, reject) => {
-    _logIOS(resolve, reject);
-  });
-}
-
-function _logIOS() {
-  let rawDevices;
-
-  try {
-    rawDevices = child_process.execFileSync(
-      'xcrun',
-      ['simctl', 'list', 'devices', '--json'],
-      {encoding: 'utf8'},
-    );
-  } catch (e) {
-    console.log(
-      chalk.red(
-        'xcrun invocation failed. Please check that Xcode is installed.',
-      ),
-    );
-    return Promise.reject(e);
-  }
+async function logIOS() {
+  const rawDevices = execFileSync(
+    'xcrun',
+    ['simctl', 'list', 'devices', '--json'],
+    { encoding: 'utf8' }
+  );
 
-  const {devices} = JSON.parse(rawDevices);
+  const { devices } = JSON.parse(rawDevices);
 
-  const device = _findAvailableDevice(devices);
+  const device = findAvailableDevice(devices);
   if (device === undefined) {
     console.log(chalk.red('No active iOS device found'));
-    return Promise.reject();
+    return;
   }
 
-  return tailDeviceLogs(device.udid);
-}
-
-function _findAvailableDevice(devices) {
-  for (const key of Object.keys(devices)) {
-    for (const device of devices[key]) {
-      if (device.availability === '(available)' && device.state === 'Booted') {
-        return device;
-      }
-    }
-  }
+  tailDeviceLogs(device.udid);
 }
 
 function tailDeviceLogs(udid) {
@@ -69,18 +51,15 @@ function tailDeviceLogs(udid) {
     'Logs',
     'CoreSimulator',
     udid,
-    'asl',
+    'asl'
   );
 
-  const log = child_process.spawnSync(
-    'syslog',
-    ['-w', '-F', 'std', '-d', logDir],
-    {stdio: 'inherit'},
-  );
+  const log = spawnSync('syslog', ['-w', '-F', 'std', '-d', logDir], {
+    stdio: 'inherit',
+  });
 
   if (log.error !== null) {
-    console.log(chalk.red('syslog invocation failed.'));
-    return Promise.reject(log.error);
+    throw log.error;
   }
 }
 
diff --git a/packages/local-cli/package.json b/packages/local-cli/package.json
index dba501f07..b4aa4e334 100644
--- a/packages/local-cli/package.json
+++ b/packages/local-cli/package.json
@@ -57,7 +57,6 @@
     "node-notifier": "^5.2.1",
     "npmlog": "^2.0.4",
     "opn": "^3.0.2",
-    "optimist": "^0.6.1",
     "plist": "^3.0.0",
     "promise": "^7.1.1",
     "semver": "^5.0.3",
@@ -68,6 +67,7 @@
     "xmldoc": "^0.4.0"
   },
   "devDependencies": {
+    "@babel/plugin-transform-strict-mode": "^7.2.0",
     "babel-core": "7.0.0-bridge.0",
     "babel-jest": "24.0.0-alpha.6",
     "eslint": "^5.7.0",
diff --git a/packages/local-cli/runAndroid/adb.js b/packages/local-cli/runAndroid/adb.js
index 7846a4724..27f03054d 100644
--- a/packages/local-cli/runAndroid/adb.js
+++ b/packages/local-cli/runAndroid/adb.js
@@ -8,7 +8,7 @@
  * @flow strict
  */
 
-const child_process = require('child_process');
+const { execSync } = require('child_process');
 
 /**
  * Parses the output of the 'adb devices' command
@@ -22,7 +22,7 @@ function parseDevicesResult(result: string): Array<string> {
   const lines = result.trim().split(/\r?\n/);
 
   for (let i = 0; i < lines.length; i++) {
-    let words = lines[i].split(/[ ,\t]+/).filter(w => w !== '');
+    const words = lines[i].split(/[ ,\t]+/).filter(w => w !== '');
 
     if (words[1] === 'device') {
       devices.push(words[0]);
@@ -36,7 +36,7 @@ function parseDevicesResult(result: string): Array<string> {
  */
 function getDevices(): Array<string> {
   try {
-    const devicesResult = child_process.execSync('adb devices');
+    const devicesResult = execSync('adb devices');
     return parseDevicesResult(devicesResult.toString());
   } catch (e) {
     return [];
@@ -44,6 +44,6 @@ function getDevices(): Array<string> {
 }
 
 module.exports = {
-  parseDevicesResult: parseDevicesResult,
-  getDevices: getDevices,
+  parseDevicesResult,
+  getDevices,
 };
diff --git a/packages/local-cli/runAndroid/runAndroid.js b/packages/local-cli/runAndroid/runAndroid.js
index f94caa266..92faaa293 100644
--- a/packages/local-cli/runAndroid/runAndroid.js
+++ b/packages/local-cli/runAndroid/runAndroid.js
@@ -4,20 +4,20 @@
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
  *
- * @format
+ * @flow
  */
 
-'use strict';
+/* eslint-disable consistent-return */
 
-const adb = require('./adb');
 const chalk = require('chalk');
-const child_process = require('child_process');
+const { spawnSync, spawn, execFileSync } = require('child_process');
 const fs = require('fs');
-const isPackagerRunning = require('../util/isPackagerRunning');
-const findReactNativeScripts = require('../util/findReactNativeScripts');
 const isString = require('lodash/isString');
 const path = require('path');
 const Promise = require('promise');
+const findReactNativeScripts = require('../util/findReactNativeScripts');
+const isPackagerRunning = require('../util/isPackagerRunning');
+const adb = require('./adb');
 
 // Verifies this is an Android project
 function checkAndroid(root) {
@@ -31,16 +31,16 @@ function runAndroid(argv, config, args) {
   if (!checkAndroid(args.root)) {
     const reactNativeScriptsPath = findReactNativeScripts();
     if (reactNativeScriptsPath) {
-      child_process.spawnSync(
+      spawnSync(
         reactNativeScriptsPath,
         ['android'].concat(process.argv.slice(1)),
-        {stdio: 'inherit'},
+        { stdio: 'inherit' }
       );
     } else {
       console.log(
         chalk.red(
-          'Android project not found. Maybe run react-native android first?',
-        ),
+          'Android project not found. Maybe run react-native android first?'
+        )
       );
     }
     return;
@@ -55,7 +55,7 @@ function runAndroid(argv, config, args) {
       console.log(chalk.bold('JS server already running.'));
     } else if (result === 'unrecognized') {
       console.warn(
-        chalk.yellow('JS server not recognized, continuing with build...'),
+        chalk.yellow('JS server not recognized, continuing with build...')
       );
     } else {
       // result == 'not_running'
@@ -68,7 +68,7 @@ function runAndroid(argv, config, args) {
 
 function getAdbPath() {
   return process.env.ANDROID_HOME
-    ? process.env.ANDROID_HOME + '/platform-tools/adb'
+    ? `${process.env.ANDROID_HOME}/platform-tools/adb`
     : 'adb';
 }
 
@@ -85,7 +85,7 @@ function tryRunAdbReverse(packagerPort, device) {
 
     console.log(chalk.bold(`Running ${adbPath} ${adbArgs.join(' ')}`));
 
-    child_process.execFileSync(adbPath, adbArgs, {
+    execFileSync(adbPath, adbArgs, {
       stdio: [process.stdin, process.stdout, process.stderr],
     });
   } catch (e) {
@@ -96,8 +96,9 @@ function tryRunAdbReverse(packagerPort, device) {
 function getPackageNameWithSuffix(appId, appIdSuffix, packageName) {
   if (appId) {
     return appId;
-  } else if (appIdSuffix) {
-    return packageName + '.' + appIdSuffix;
+  }
+  if (appIdSuffix) {
+    return `${packageName}.${appIdSuffix}`;
   }
 
   return packageName;
@@ -115,7 +116,7 @@ function buildAndRun(args) {
   const packageNameWithSuffix = getPackageNameWithSuffix(
     args.appId,
     args.appIdSuffix,
-    packageName,
+    packageName
   );
 
   const adbPath = getAdbPath();
@@ -126,18 +127,17 @@ function buildAndRun(args) {
         cmd,
         packageNameWithSuffix,
         packageName,
-        adbPath,
+        adbPath
       );
-    } else {
-      console.log(chalk.red('Argument missing for parameter --deviceId'));
     }
+    console.log(chalk.red('Argument missing for parameter --deviceId'));
   } else {
     return runOnAllDevices(
       args,
       cmd,
       packageNameWithSuffix,
       packageName,
-      adbPath,
+      adbPath
     );
   }
 }
@@ -147,9 +147,9 @@ function runOnSpecificDevice(
   gradlew,
   packageNameWithSuffix,
   packageName,
-  adbPath,
+  adbPath
 ) {
-  let devices = adb.getDevices();
+  const devices = adb.getDevices();
   if (devices && devices.length > 0) {
     if (devices.indexOf(args.deviceId) !== -1) {
       buildApk(gradlew);
@@ -158,12 +158,10 @@ function runOnSpecificDevice(
         args.deviceId,
         packageNameWithSuffix,
         packageName,
-        adbPath,
+        adbPath
       );
     } else {
-      console.log(
-        'Could not find device with the id: "' + args.deviceId + '".',
-      );
+      console.log(`Could not find device with the id: "${args.deviceId}".`);
       console.log('Choose one of the following:');
       console.log(devices);
     }
@@ -177,12 +175,12 @@ function buildApk(gradlew) {
     console.log(chalk.bold('Building the app...'));
 
     // using '-x lint' in order to ignore linting errors while building the apk
-    child_process.execFileSync(gradlew, ['build', '-x', 'lint'], {
+    execFileSync(gradlew, ['build', '-x', 'lint'], {
       stdio: [process.stdin, process.stdout, process.stderr],
     });
   } catch (e) {
     console.log(
-      chalk.red('Could not build the app, read the error above for details.\n'),
+      chalk.red('Could not build the app, read the error above for details.\n')
     );
   }
 }
@@ -196,18 +194,18 @@ function tryInstallAppOnDevice(args, device) {
     const adbArgs = ['-s', device, 'install', pathToApk];
     console.log(
       chalk.bold(
-        `Installing the app on the device (cd android && adb -s ${device} install ${pathToApk}`,
-      ),
+        `Installing the app on the device (cd android && adb -s ${device} install ${pathToApk}`
+      )
     );
-    child_process.execFileSync(adbPath, adbArgs, {
+    execFileSync(adbPath, adbArgs, {
       stdio: [process.stdin, process.stdout, process.stderr],
     });
   } catch (e) {
     console.log(e.message);
     console.log(
       chalk.red(
-        'Could not install the app on the device, read the error above for details.\n',
-      ),
+        'Could not install the app on the device, read the error above for details.\n'
+      )
     );
   }
 }
@@ -217,7 +215,7 @@ function tryLaunchAppOnDevice(
   packageNameWithSuffix,
   packageName,
   adbPath,
-  mainActivity,
+  mainActivity
 ) {
   try {
     const adbArgs = [
@@ -227,17 +225,17 @@ function tryLaunchAppOnDevice(
       'am',
       'start',
       '-n',
-      packageNameWithSuffix + '/' + packageName + '.' + mainActivity,
+      `${packageNameWithSuffix}/${packageName}.${mainActivity}`,
     ];
     console.log(
       chalk.bold(
-        `Starting the app on ${device} (${adbPath} ${adbArgs.join(' ')})...`,
-      ),
+        `Starting the app on ${device} (${adbPath} ${adbArgs.join(' ')})...`
+      )
     );
-    child_process.spawnSync(adbPath, adbArgs, {stdio: 'inherit'});
+    spawnSync(adbPath, adbArgs, { stdio: 'inherit' });
   } catch (e) {
     console.log(
-      chalk.red('adb invocation failed. Do you have adb in your PATH?'),
+      chalk.red('adb invocation failed. Do you have adb in your PATH?')
     );
   }
 }
@@ -247,7 +245,7 @@ function installAndLaunchOnDevice(
   selectedDevice,
   packageNameWithSuffix,
   packageName,
-  adbPath,
+  adbPath
 ) {
   tryRunAdbReverse(args.port, selectedDevice);
   tryInstallAppOnDevice(args, selectedDevice);
@@ -256,7 +254,7 @@ function installAndLaunchOnDevice(
     packageNameWithSuffix,
     packageName,
     adbPath,
-    args.mainActivity,
+    args.mainActivity
   );
 }
 
@@ -265,20 +263,20 @@ function runOnAllDevices(
   cmd,
   packageNameWithSuffix,
   packageName,
-  adbPath,
+  adbPath
 ) {
   try {
     const gradleArgs = [];
     if (args.variant) {
       gradleArgs.push(
-        'install' + args.variant[0].toUpperCase() + args.variant.slice(1),
+        `install${args.variant[0].toUpperCase()}${args.variant.slice(1)}`
       );
     } else if (args.flavor) {
       console.warn(
-        chalk.yellow('--flavor has been deprecated. Use --variant instead'),
+        chalk.yellow('--flavor has been deprecated. Use --variant instead')
       );
       gradleArgs.push(
-        'install' + args.flavor[0].toUpperCase() + args.flavor.slice(1),
+        `install${args.flavor[0].toUpperCase()}${args.flavor.slice(1)}`
       );
     } else {
       gradleArgs.push('installDebug');
@@ -291,12 +289,12 @@ function runOnAllDevices(
     console.log(
       chalk.bold(
         `Building and installing the app on the device (cd android && ${cmd} ${gradleArgs.join(
-          ' ',
-        )})...`,
-      ),
+          ' '
+        )})...`
+      )
     );
 
-    child_process.execFileSync(cmd, gradleArgs, {
+    execFileSync(cmd, gradleArgs, {
       stdio: [process.stdin, process.stdout, process.stderr],
     });
   } catch (e) {
@@ -305,8 +303,8 @@ function runOnAllDevices(
         'Could not install the app on the device, read the error above for details.\n' +
           'Make sure you have an Android emulator running or a device connected and have\n' +
           'set up your Android development environment:\n' +
-          'https://facebook.github.io/react-native/docs/getting-started.html',
-      ),
+          'https://facebook.github.io/react-native/docs/getting-started.html'
+      )
     );
     // stderr is automatically piped from the gradle process, so the user
     // should see the error already, there is no need to do
@@ -322,7 +320,7 @@ function runOnAllDevices(
         packageNameWithSuffix,
         packageName,
         adbPath,
-        args.mainActivity,
+        args.mainActivity
       );
     });
   } else {
@@ -334,17 +332,17 @@ function runOnAllDevices(
         'am',
         'start',
         '-n',
-        packageNameWithSuffix + '/' + packageName + '.MainActivity',
+        `${packageNameWithSuffix}/${packageName}.MainActivity`,
       ];
       console.log(
         chalk.bold(
-          `Starting the app (${adbPath} ${fallbackAdbArgs.join(' ')}...`,
-        ),
+          `Starting the app (${adbPath} ${fallbackAdbArgs.join(' ')}...`
+        )
       );
-      child_process.spawnSync(adbPath, fallbackAdbArgs, {stdio: 'inherit'});
+      spawnSync(adbPath, fallbackAdbArgs, { stdio: 'inherit' });
     } catch (e) {
       console.log(
-        chalk.red('adb invocation failed. Do you have adb in your PATH?'),
+        chalk.red('adb invocation failed. Do you have adb in your PATH?')
       );
       // stderr is automatically piped from the gradle process, so the user
       // should see the error already, there is no need to do
@@ -368,7 +366,7 @@ function startServerInNewWindow(port, terminal = process.env.REACT_TERMINAL) {
   // set up the launchpackager.(command|bat) file
   const scriptsDir = path.resolve(__dirname, '..', '..', 'scripts');
   const launchPackagerScript = path.resolve(scriptsDir, scriptFile);
-  const procConfig = {cwd: scriptsDir};
+  const procConfig = { cwd: scriptsDir };
 
   // set up the .packager.(env|bat) file to ensure the packager starts on the right port
   const packagerEnvFile = path.join(
@@ -376,7 +374,7 @@ function startServerInNewWindow(port, terminal = process.env.REACT_TERMINAL) {
     '..',
     '..',
     'scripts',
-    packagerEnvFilename,
+    packagerEnvFilename
   );
 
   // ensure we overwrite file by passing the 'w' flag
@@ -387,40 +385,31 @@ function startServerInNewWindow(port, terminal = process.env.REACT_TERMINAL) {
 
   if (process.platform === 'darwin') {
     if (terminal) {
-      return child_process.spawnSync(
+      return spawnSync(
         'open',
         ['-a', terminal, launchPackagerScript],
-        procConfig,
+        procConfig
       );
     }
-    return child_process.spawnSync('open', [launchPackagerScript], procConfig);
-  } else if (process.platform === 'linux') {
+    return spawnSync('open', [launchPackagerScript], procConfig);
+  }
+  if (process.platform === 'linux') {
     if (terminal) {
       procConfig.detached = true;
-      return child_process.spawn(
-        terminal,
-        ['-e', 'sh ' + launchPackagerScript],
-        procConfig,
-      );
+      return spawn(terminal, ['-e', `sh ${launchPackagerScript}`], procConfig);
     }
     // By default, the child shell process will be attached to the parent
     procConfig.detached = false;
-    return child_process.spawn('sh', [launchPackagerScript], procConfig);
-  } else if (/^win/.test(process.platform)) {
+    return spawn('sh', [launchPackagerScript], procConfig);
+  }
+  if (/^win/.test(process.platform)) {
     procConfig.detached = true;
     procConfig.stdio = 'ignore';
-    return child_process.spawn(
-      'cmd.exe',
-      ['/C', launchPackagerScript],
-      procConfig,
-    );
-  } else {
-    console.log(
-      chalk.red(
-        `Cannot start the packager. Unknown platform ${process.platform}`,
-      ),
-    );
+    return spawn('cmd.exe', ['/C', launchPackagerScript], procConfig);
   }
+  console.log(
+    chalk.red(`Cannot start the packager. Unknown platform ${process.platform}`)
+  );
 }
 
 module.exports = {
diff --git a/packages/local-cli/runIOS/__tests__/findMatchingSimulator-test.js b/packages/local-cli/runIOS/__tests__/findMatchingSimulator-test.js
index 8b9a19552..f868c3484 100644
--- a/packages/local-cli/runIOS/__tests__/findMatchingSimulator-test.js
+++ b/packages/local-cli/runIOS/__tests__/findMatchingSimulator-test.js
@@ -9,8 +9,6 @@
  * @emails oncall+javascript_foundation
  */
 
-'use strict';
-
 jest.dontMock('../findMatchingSimulator');
 
 const findMatchingSimulator = require('../findMatchingSimulator');
@@ -55,8 +53,8 @@ describe('findMatchingSimulator', () => {
             ],
           },
         },
-        'iPhone 6',
-      ),
+        'iPhone 6'
+      )
     ).toEqual({
       udid: 'BA0D93BD-07E6-4182-9B0A-F60A2474139C',
       name: 'iPhone 6',
@@ -107,8 +105,8 @@ describe('findMatchingSimulator', () => {
             ],
           },
         },
-        'iPhone 6',
-      ),
+        'iPhone 6'
+      )
     ).toEqual({
       udid: 'BA0D93BD-07E6-4182-9B0A-F60A2474139C',
       name: 'iPhone 6',
@@ -156,14 +154,14 @@ describe('findMatchingSimulator', () => {
             ],
           },
         },
-        'iPhone 6',
-      ),
+        'iPhone 6'
+      )
     ).toEqual(null);
   });
 
   it('should return null if an odd input', () => {
     expect(findMatchingSimulator('random string input', 'iPhone 6')).toEqual(
-      null,
+      null
     );
   });
 
@@ -206,8 +204,8 @@ describe('findMatchingSimulator', () => {
             ],
           },
         },
-        null,
-      ),
+        null
+      )
     ).toEqual({
       udid: '1CCBBF8B-5773-4EA6-BD6F-C308C87A1ADB',
       name: 'iPhone 5',
@@ -216,7 +214,7 @@ describe('findMatchingSimulator', () => {
     });
   });
 
-  it('should return the first simulator in list if none is defined', () => {
+  it('should return the first simulator with the correct version in list if none is defined', () => {
     expect(
       findMatchingSimulator(
         {
@@ -281,8 +279,8 @@ describe('findMatchingSimulator', () => {
             ],
           },
         },
-        null,
-      ),
+        null
+      )
     ).toEqual({
       udid: '1CCBBF8B-5773-4EA6-BD6F-C308C87A1ADB',
       name: 'iPhone 5',
@@ -330,8 +328,8 @@ describe('findMatchingSimulator', () => {
             ],
           },
         },
-        null,
-      ),
+        null
+      )
     ).toEqual({
       udid: 'D0F29BE7-CC3C-4976-888D-C739B4F50508',
       name: 'iPhone 6s',
@@ -379,8 +377,8 @@ describe('findMatchingSimulator', () => {
             ],
           },
         },
-        'iPhone 6',
-      ),
+        'iPhone 6'
+      )
     ).toEqual({
       udid: 'BA0D93BD-07E6-4182-9B0A-F60A2474139C',
       name: 'iPhone 6',
@@ -454,8 +452,8 @@ describe('findMatchingSimulator', () => {
             ],
           },
         },
-        null,
-      ),
+        null
+      )
     ).toEqual({
       udid: '3A409DC5-5188-42A6-8598-3AA6F34607A5',
       name: 'iPhone 7',
@@ -529,8 +527,8 @@ describe('findMatchingSimulator', () => {
             ],
           },
         },
-        'iPhone 6s',
-      ),
+        'iPhone 6s'
+      )
     ).toEqual({
       udid: 'D0F29BE7-CC3C-4976-888D-C739B4F50508',
       name: 'iPhone 6s',
@@ -604,8 +602,8 @@ describe('findMatchingSimulator', () => {
             ],
           },
         },
-        'iPhone 6s (10.0)',
-      ),
+        'iPhone 6s (10.0)'
+      )
     ).toEqual({
       udid: 'CBBB8FB8-77AB-49A9-8297-4CCFE3189C22',
       name: 'iPhone 6s',
@@ -673,8 +671,8 @@ describe('findMatchingSimulator', () => {
             ],
           },
         },
-        'iPhone 6s (10.0)',
-      ),
+        'iPhone 6s (10.0)'
+      )
     ).toEqual(null);
   });
 
@@ -705,8 +703,8 @@ describe('findMatchingSimulator', () => {
             ],
           },
         },
-        'Apple TV',
-      ),
+        'Apple TV'
+      )
     ).toEqual({
       udid: '816C30EA-38EA-41AC-BFDA-96FB632D522E',
       name: 'Apple TV',
diff --git a/packages/local-cli/runIOS/__tests__/findXcodeProject-test.js b/packages/local-cli/runIOS/__tests__/findXcodeProject-test.js
index 8071d728f..7cac685b7 100644
--- a/packages/local-cli/runIOS/__tests__/findXcodeProject-test.js
+++ b/packages/local-cli/runIOS/__tests__/findXcodeProject-test.js
@@ -8,8 +8,6 @@
  * @emails oncall+javascript_foundation
  */
 
-'use strict';
-
 jest.dontMock('../findXcodeProject');
 
 const findXcodeProject = require('../findXcodeProject');
@@ -25,7 +23,7 @@ describe('findXcodeProject', () => {
         'PodFile',
         'Podfile.lock',
         'Pods',
-      ]),
+      ])
     ).toEqual({
       name: 'AwesomeApp.xcodeproj',
       isWorkspace: false,
@@ -43,7 +41,7 @@ describe('findXcodeProject', () => {
         'PodFile',
         'Podfile.lock',
         'Pods',
-      ]),
+      ])
     ).toEqual({
       name: 'AwesomeApp.xcworkspace',
       isWorkspace: true,
@@ -59,7 +57,7 @@ describe('findXcodeProject', () => {
         'PodFile',
         'Podfile.lock',
         'Pods',
-      ]),
+      ])
     ).toEqual(null);
   });
 });
diff --git a/packages/local-cli/runIOS/__tests__/parseIOSDevicesList-test.js b/packages/local-cli/runIOS/__tests__/parseIOSDevicesList-test.js
index 8914b5937..206fbbe4e 100644
--- a/packages/local-cli/runIOS/__tests__/parseIOSDevicesList-test.js
+++ b/packages/local-cli/runIOS/__tests__/parseIOSDevicesList-test.js
@@ -8,14 +8,12 @@
  * @emails oncall+javascript_foundation
  */
 
-'use strict';
-
 jest.dontMock('../parseIOSDevicesList');
-var parseIOSDevicesList = require('../parseIOSDevicesList');
+const parseIOSDevicesList = require('../parseIOSDevicesList');
 
 describe('parseIOSDevicesList', () => {
   it('parses typical output', () => {
-    var devices = parseIOSDevicesList(
+    const devices = parseIOSDevicesList(
       [
         'Known Devices:',
         'Maxs MacBook Pro [11111111-1111-1111-1111-111111111111]',
@@ -28,7 +26,7 @@ describe('parseIOSDevicesList', () => {
         'Blank',
         'System Usage',
         'Zombies',
-      ].join('\n'),
+      ].join('\n')
     );
 
     expect(devices).toEqual([
@@ -42,7 +40,7 @@ describe('parseIOSDevicesList', () => {
 
   it('ignores garbage', () => {
     expect(parseIOSDevicesList('Something went terribly wrong (-42)')).toEqual(
-      [],
+      []
     );
   });
 });
diff --git a/packages/local-cli/runIOS/findMatchingSimulator.js b/packages/local-cli/runIOS/findMatchingSimulator.js
index 30e2156d4..2de9d1c99 100644
--- a/packages/local-cli/runIOS/findMatchingSimulator.js
+++ b/packages/local-cli/runIOS/findMatchingSimulator.js
@@ -7,7 +7,7 @@
  * @format
  */
 
-'use strict';
+/* eslint-disable */
 
 /**
  * Takes in a parsed simulator list and a desired name, and returns an object with the matching simulator. The desired
@@ -38,8 +38,8 @@ function findMatchingSimulator(simulators, simulatorString) {
     simulatorName = simulatorString;
   }
 
-  var match;
-  for (let version in devices) {
+  let match;
+  for (const version in devices) {
     // Making sure the version of the simulator is an iOS or tvOS (Removes Apple Watch, etc)
     if (!version.startsWith('iOS') && !version.startsWith('tvOS')) {
       continue;
@@ -47,8 +47,8 @@ function findMatchingSimulator(simulators, simulatorString) {
     if (simulatorVersion && !version.endsWith(simulatorVersion)) {
       continue;
     }
-    for (let i in devices[version]) {
-      let simulator = devices[version][i];
+    for (const i in devices[version]) {
+      const simulator = devices[version][i];
       // Skipping non-available simulator
       if (
         simulator.availability !== '(available)' &&
@@ -56,7 +56,7 @@ function findMatchingSimulator(simulators, simulatorString) {
       ) {
         continue;
       }
-      let booted = simulator.state === 'Booted';
+      const booted = simulator.state === 'Booted';
       if (booted && simulatorName === null) {
         return {
           udid: simulator.udid,
diff --git a/packages/local-cli/runIOS/findXcodeProject.js b/packages/local-cli/runIOS/findXcodeProject.js
index 318f11ec8..5e94e7928 100644
--- a/packages/local-cli/runIOS/findXcodeProject.js
+++ b/packages/local-cli/runIOS/findXcodeProject.js
@@ -8,8 +8,6 @@
  * @flow strict
  */
 
-'use strict';
-
 const path = require('path');
 
 type ProjectInfo = {
diff --git a/packages/local-cli/runIOS/parseIOSDevicesList.js b/packages/local-cli/runIOS/parseIOSDevicesList.js
index 0209c796b..a7628f3c0 100644
--- a/packages/local-cli/runIOS/parseIOSDevicesList.js
+++ b/packages/local-cli/runIOS/parseIOSDevicesList.js
@@ -8,8 +8,6 @@
  * @flow strict
  */
 
-'use strict';
-
 type IOSDeviceInfo = {
   name: string,
   udid: string,
@@ -25,10 +23,10 @@ function parseIOSDevicesList(text: string): Array<IOSDeviceInfo> {
     const device = line.match(/(.*?) \((.*?)\) \[(.*?)\]/);
     const noSimulator = line.match(/(.*?) \((.*?)\) \[(.*?)\] \((.*?)\)/);
     if (device != null && noSimulator == null) {
-      var name = device[1];
-      var version = device[2];
-      var udid = device[3];
-      devices.push({udid, name, version});
+      const name = device[1];
+      const version = device[2];
+      const udid = device[3];
+      devices.push({ udid, name, version });
     }
   });
 
diff --git a/packages/local-cli/runIOS/runIOS.js b/packages/local-cli/runIOS/runIOS.js
index a7ecf7d6d..de61b8930 100644
--- a/packages/local-cli/runIOS/runIOS.js
+++ b/packages/local-cli/runIOS/runIOS.js
@@ -7,7 +7,7 @@
  * @format
  */
 
-'use strict';
+/* eslint-disable */
 
 const child_process = require('child_process');
 const fs = require('fs');
@@ -16,6 +16,7 @@ const findXcodeProject = require('./findXcodeProject');
 const findReactNativeScripts = require('../util/findReactNativeScripts');
 const parseIOSDevicesList = require('./parseIOSDevicesList');
 const findMatchingSimulator = require('./findMatchingSimulator');
+
 const getBuildPath = function(configuration = 'Debug', appName, isDevice) {
   let device;
 
@@ -47,14 +48,13 @@ function runIOS(argv, config, args) {
       child_process.spawnSync(
         reactNativeScriptsPath,
         ['ios'].concat(process.argv.slice(1)),
-        {stdio: 'inherit'},
+        { stdio: 'inherit' }
       );
       return;
-    } else {
-      throw new Error(
-        'iOS project folder not found. Are you sure this is a React Native project?',
-      );
     }
+    throw new Error(
+      'iOS project folder not found. Are you sure this is a React Native project?'
+    );
   }
   process.chdir(args.projectPath);
   const xcodeProject = findXcodeProject(fs.readdirSync('.'));
@@ -64,18 +64,18 @@ function runIOS(argv, config, args) {
 
   const inferredSchemeName = path.basename(
     xcodeProject.name,
-    path.extname(xcodeProject.name),
+    path.extname(xcodeProject.name)
   );
   const scheme = args.scheme || inferredSchemeName;
   console.log(
     `Found Xcode ${xcodeProject.isWorkspace ? 'workspace' : 'project'} ${
       xcodeProject.name
-    }`,
+    }`
   );
   const devices = parseIOSDevicesList(
     child_process.execFileSync('xcrun', ['instruments', '-s'], {
       encoding: 'utf8',
-    }),
+    })
   );
   if (args.device) {
     const selectedDevice = matchingDevice(devices, args.device);
@@ -87,18 +87,15 @@ function runIOS(argv, config, args) {
         args.configuration,
         args.packager,
         args.verbose,
-        args.port,
+        args.port
       );
+    }
+    if (devices && devices.length > 0) {
+      console.log(`Could not find device with the name: "${args.device}".`);
+      console.log('Choose one of the following:');
+      printFoundDevices(devices);
     } else {
-      if (devices && devices.length > 0) {
-        console.log(
-          'Could not find device with the name: "' + args.device + '".',
-        );
-        console.log('Choose one of the following:');
-        printFoundDevices(devices);
-      } else {
-        console.log('No iOS devices connected.');
-      }
+      console.log('No iOS devices connected.');
     }
   } else if (args.udid) {
     return runOnDeviceByUdid(args, scheme, xcodeProject, devices);
@@ -117,16 +114,15 @@ function runOnDeviceByUdid(args, scheme, xcodeProject, devices) {
       args.configuration,
       args.packager,
       args.verbose,
-      args.port,
+      args.port
     );
+  }
+  if (devices && devices.length > 0) {
+    console.log(`Could not find device with the udid: "${args.udid}".`);
+    console.log('Choose one of the following:');
+    printFoundDevices(devices);
   } else {
-    if (devices && devices.length > 0) {
-      console.log('Could not find device with the udid: "' + args.udid + '".');
-      console.log('Choose one of the following:');
-      printFoundDevices(devices);
-    } else {
-      console.log('No iOS devices connected.');
-    }
+    console.log('No iOS devices connected.');
   }
 }
 
@@ -137,8 +133,8 @@ function runOnSimulator(xcodeProject, args, scheme) {
         child_process.execFileSync(
           'xcrun',
           ['simctl', 'list', '--json', 'devices'],
-          {encoding: 'utf8'},
-        ),
+          { encoding: 'utf8' }
+        )
       );
     } catch (e) {
       throw new Error('Could not parse the simulator list output');
@@ -161,7 +157,7 @@ function runOnSimulator(xcodeProject, args, scheme) {
      * this flag has no effect.
      */
     const activeDeveloperDir = child_process
-      .execFileSync('xcode-select', ['-p'], {encoding: 'utf8'})
+      .execFileSync('xcode-select', ['-p'], { encoding: 'utf8' })
       .trim();
     child_process.execFileSync('open', [
       `${activeDeveloperDir}/Applications/Simulator.app`,
@@ -192,13 +188,13 @@ function runOnSimulator(xcodeProject, args, scheme) {
       args.configuration,
       args.packager,
       args.verbose,
-      args.port,
-    ).then(appName => resolve({udid: selectedSimulator.udid, appName}));
-  }).then(({udid, appName}) => {
+      args.port
+    ).then(appName => resolve({ udid: selectedSimulator.udid, appName }));
+  }).then(({ udid, appName }) => {
     if (!appName) {
       appName = scheme;
     }
-    let appPath = getBuildPath(args.configuration, appName);
+    const appPath = getBuildPath(args.configuration, appName);
     console.log(`Installing ${appPath}`);
     child_process.spawnSync('xcrun', ['simctl', 'install', udid, appPath], {
       stdio: 'inherit',
@@ -208,7 +204,7 @@ function runOnSimulator(xcodeProject, args, scheme) {
       .execFileSync(
         '/usr/libexec/PlistBuddy',
         ['-c', 'Print:CFBundleIdentifier', path.join(appPath, 'Info.plist')],
-        {encoding: 'utf8'},
+        { encoding: 'utf8' }
       )
       .trim();
 
@@ -226,7 +222,7 @@ function runOnDevice(
   configuration,
   launchPackager,
   verbose,
-  port,
+  port
 ) {
   return buildProject(
     xcodeProject,
@@ -235,7 +231,7 @@ function runOnDevice(
     configuration,
     launchPackager,
     verbose,
-    port,
+    port
   ).then(appName => {
     if (!appName) {
       appName = scheme;
@@ -248,12 +244,12 @@ function runOnDevice(
       '--justlaunch',
     ];
     console.log(
-      `installing and launching your app on ${selectedDevice.name}...`,
+      `installing and launching your app on ${selectedDevice.name}...`
     );
     const iosDeployOutput = child_process.spawnSync(
       'ios-deploy',
       iosDeployInstallArgs,
-      {encoding: 'utf8'},
+      { encoding: 'utf8' }
     );
     if (iosDeployOutput.error) {
       console.log('');
@@ -273,10 +269,10 @@ function buildProject(
   configuration = 'Debug',
   launchPackager = false,
   verbose,
-  port,
+  port
 ) {
   return new Promise((resolve, reject) => {
-    var xcodebuildArgs = [
+    const xcodebuildArgs = [
       xcodeProject.isWorkspace ? '-workspace' : '-project',
       xcodeProject.name,
       '-configuration',
@@ -300,10 +296,10 @@ function buildProject(
     const buildProcess = child_process.spawn(
       'xcodebuild',
       xcodebuildArgs,
-      getProcessOptions(launchPackager, port),
+      getProcessOptions(launchPackager, port)
     );
     let buildOutput = '';
-    buildProcess.stdout.on('data', function(data) {
+    buildProcess.stdout.on('data', data => {
       buildOutput += data.toString();
       if (xcpretty) {
         xcpretty.stdin.write(data);
@@ -311,23 +307,23 @@ function buildProject(
         console.log(data.toString());
       }
     });
-    buildProcess.stderr.on('data', function(data) {
+    buildProcess.stderr.on('data', data => {
       console.error(data.toString());
     });
-    buildProcess.on('close', function(code) {
+    buildProcess.on('close', code => {
       if (xcpretty) {
         xcpretty.stdin.end();
       }
-      //FULL_PRODUCT_NAME is the actual file name of the app, which actually comes from the Product Name in the build config, which does not necessary match a scheme name,  example output line: export FULL_PRODUCT_NAME="Super App Dev.app"
-      let productNameMatch = /export FULL_PRODUCT_NAME="?(.+).app"?$/m.exec(
-        buildOutput,
+      // FULL_PRODUCT_NAME is the actual file name of the app, which actually comes from the Product Name in the build config, which does not necessary match a scheme name,  example output line: export FULL_PRODUCT_NAME="Super App Dev.app"
+      const productNameMatch = /export FULL_PRODUCT_NAME="?(.+).app"?$/m.exec(
+        buildOutput
       );
       if (
         productNameMatch &&
         productNameMatch.length &&
         productNameMatch.length > 1
       ) {
-        return resolve(productNameMatch[1]); //0 is the full match, 1 is the app name
+        return resolve(productNameMatch[1]); // 0 is the full match, 1 is the app name
       }
       return buildProcess.error ? reject(buildProcess.error) : resolve();
     });
@@ -339,7 +335,7 @@ function matchingDevice(devices, deviceName) {
     console.log(
       `Using first available device ${
         devices[0].name
-      } due to lack of name supplied.`,
+      } due to lack of name supplied.`
     );
     return devices[0];
   }
@@ -367,19 +363,19 @@ function formattedDeviceName(simulator) {
 
 function printFoundDevices(devices) {
   for (let i = devices.length - 1; i >= 0; i--) {
-    console.log(devices[i].name + ' Udid: ' + devices[i].udid);
+    console.log(`${devices[i].name} Udid: ${devices[i].udid}`);
   }
 }
 
 function getProcessOptions(launchPackager, port) {
   if (launchPackager) {
     return {
-      env: {...process.env, RCT_METRO_PORT: port},
+      env: { ...process.env, RCT_METRO_PORT: port },
     };
   }
 
   return {
-    env: {...process.env, RCT_NO_LAUNCH_PACKAGER: true},
+    env: { ...process.env, RCT_NO_LAUNCH_PACKAGER: true },
   };
 }
 
diff --git a/packages/local-cli/server/middleware/MiddlewareManager.js b/packages/local-cli/server/middleware/MiddlewareManager.js
index 8d1ec3835..c1c529432 100644
--- a/packages/local-cli/server/middleware/MiddlewareManager.js
+++ b/packages/local-cli/server/middleware/MiddlewareManager.js
@@ -17,7 +17,7 @@ const WebSocketServer = require('ws').Server;
 
 const indexPageMiddleware = require('./indexPage');
 const copyToClipBoardMiddleware = require('./copyToClipBoardMiddleware');
-const getSecurityHeadersMiddleware =  require('./getSecurityHeadersMiddleware');
+const getSecurityHeadersMiddleware = require('./getSecurityHeadersMiddleware');
 const loadRawBodyMiddleware = require('./loadRawBodyMiddleware');
 const openStackFrameInEditorMiddleware = require('./openStackFrameInEditorMiddleware');
 const statusPageMiddleware = require('./statusPageMiddleware');
@@ -27,7 +27,7 @@ const getDevToolsMiddleware = require('./getDevToolsMiddleware');
 type Options = {
   +watchFolders: $ReadOnlyArray<string>,
   +host?: string,
-}
+};
 
 type WebSocketProxy = {
   server: WebSocketServer,
@@ -38,6 +38,7 @@ type Connect = $Call<connect>;
 
 module.exports = class MiddlewareManager {
   app: Connect;
+
   options: Options;
 
   constructor(options: Options) {
@@ -67,7 +68,7 @@ module.exports = class MiddlewareManager {
 
   attachDevToolsSocket(socket: WebSocketProxy) {
     this.app.use(
-      getDevToolsMiddleware(this.options, () => socket.isChromeConnected()),
+      getDevToolsMiddleware(this.options, () => socket.isChromeConnected())
     );
-  };
+  }
 };
diff --git a/packages/local-cli/server/middleware/copyToClipBoardMiddleware.js b/packages/local-cli/server/middleware/copyToClipBoardMiddleware.js
index 69a3171f9..0d6803bb4 100644
--- a/packages/local-cli/server/middleware/copyToClipBoardMiddleware.js
+++ b/packages/local-cli/server/middleware/copyToClipBoardMiddleware.js
@@ -7,18 +7,16 @@
  * @format
  */
 
-'use strict';
-
+const chalk = require('chalk');
 const copyToClipBoard = require('../util/copyToClipBoard');
-var chalk = require('chalk');
 
 /**
  * Handle the request from JS to copy contents onto host system clipboard.
  * This is only supported on Mac for now.
  */
-module.exports = function(req, res, next) {
+module.exports = function copyMiddleware(req, res, next) {
   if (req.url === '/copy-to-clipboard') {
-    var ret = copyToClipBoard(req.rawBody);
+    const ret = copyToClipBoard(req.rawBody);
     if (!ret) {
       console.warn(chalk.red('Copy button is not supported on this platform!'));
     }
diff --git a/packages/local-cli/server/middleware/getDevToolsMiddleware.js b/packages/local-cli/server/middleware/getDevToolsMiddleware.js
index 812872752..dffcec451 100644
--- a/packages/local-cli/server/middleware/getDevToolsMiddleware.js
+++ b/packages/local-cli/server/middleware/getDevToolsMiddleware.js
@@ -6,23 +6,14 @@
  *
  * @format
  */
-'use strict';
-
 const launchChrome = require('../util/launchChrome');
 
-const {exec} = require('child_process');
-
 function launchChromeDevTools(host, port, args = '') {
   const debuggerURL = `http://${host}:${port}/debugger-ui${args}`;
   console.log('Launching Dev Tools...');
   launchChrome(debuggerURL);
 }
 
-function escapePath(pathname) {
-  // " Can escape paths with spaces in OS X, Windows, and *nix
-  return `"${pathname}"`;
-}
-
 function launchDevTools({ host, port, watchFolders }, isChromeConnected) {
   // Explicit config always wins
   const customDebugger = process.env.REACT_DEBUGGER;
@@ -34,24 +25,13 @@ function launchDevTools({ host, port, watchFolders }, isChromeConnected) {
   }
 }
 
-function customDebugger({ watchFolders, customDebugger }) {
-  const folders = watchFolders.map(escapePath).join(' ');
-  const command = `${customDebugger} ${folders}`;
-  console.log('Starting custom debugger by executing:', command);
-  exec(command, function(error, stdout, stderr) {
-    if (error !== null) {
-      console.log('Error while starting custom debugger:', error);
-    }
-  });
-}
-
-module.exports = function(options, isChromeConnected) {
-  return function(req, res, next) {
+module.exports = function getDevToolsMiddleware(options, isChromeConnected) {
+  return function devToolsMiddleware(req, res, next) {
     if (req.url === '/launch-safari-devtools') {
       // TODO: remove `console.log` and dev tools binary
       console.log(
         'We removed support for Safari dev-tools. ' +
-          'If you still need this, please let us know.',
+          'If you still need this, please let us know.'
       );
     } else if (req.url === '/launch-chrome-devtools') {
       // TODO: Remove this case in the future
@@ -59,7 +39,7 @@ module.exports = function(options, isChromeConnected) {
         'The method /launch-chrome-devtools is deprecated. You are ' +
           ' probably using an application created with an older CLI with the ' +
           ' packager of a newer CLI. Please upgrade your application: ' +
-          'https://facebook.github.io/react-native/docs/upgrading.html',
+          'https://facebook.github.io/react-native/docs/upgrading.html'
       );
       launchDevTools(options, isChromeConnected);
       res.end('OK');
diff --git a/packages/local-cli/server/middleware/getSecurityHeadersMiddleware.js b/packages/local-cli/server/middleware/getSecurityHeadersMiddleware.js
index d3bad6bf9..a0942683c 100644
--- a/packages/local-cli/server/middleware/getSecurityHeadersMiddleware.js
+++ b/packages/local-cli/server/middleware/getSecurityHeadersMiddleware.js
@@ -8,7 +8,7 @@
  * @format
  */
 
-module.exports = function(req, res, next) {
+module.exports = function getSecurityHeadersMiddleware(req, res, next) {
   const address = req.client.server.address();
 
   // Block any cross origin request.
diff --git a/packages/local-cli/server/middleware/indexPage.js b/packages/local-cli/server/middleware/indexPage.js
index ee6fc61ad..7407bc20a 100644
--- a/packages/local-cli/server/middleware/indexPage.js
+++ b/packages/local-cli/server/middleware/indexPage.js
@@ -7,12 +7,10 @@
  * @format
  */
 
-'use strict';
-
 const fs = require('fs');
 const path = require('path');
 
-module.exports = function(req, res, next) {
+module.exports = function indexPageMiddleware(req, res, next) {
   if (req.url === '/') {
     res.end(fs.readFileSync(path.join(__dirname, 'index.html')));
   } else {
diff --git a/packages/local-cli/server/middleware/loadRawBodyMiddleware.js b/packages/local-cli/server/middleware/loadRawBodyMiddleware.js
index 553f04129..dd1d70962 100644
--- a/packages/local-cli/server/middleware/loadRawBodyMiddleware.js
+++ b/packages/local-cli/server/middleware/loadRawBodyMiddleware.js
@@ -7,17 +7,15 @@
  * @format
  */
 
-'use strict';
-
-module.exports = function(req, res, next) {
+module.exports = function rawBodyMiddleware(req, res, next) {
   req.rawBody = '';
   req.setEncoding('utf8');
 
-  req.on('data', function(chunk) {
+  req.on('data', chunk => {
     req.rawBody += chunk;
   });
 
-  req.on('end', function() {
+  req.on('end', () => {
     next();
   });
 };
diff --git a/packages/local-cli/server/middleware/openStackFrameInEditorMiddleware.js b/packages/local-cli/server/middleware/openStackFrameInEditorMiddleware.js
index 36cc69ba0..0c53c55f1 100644
--- a/packages/local-cli/server/middleware/openStackFrameInEditorMiddleware.js
+++ b/packages/local-cli/server/middleware/openStackFrameInEditorMiddleware.js
@@ -7,12 +7,12 @@
  * @format
  */
 
-'use strict';
-
 const launchEditor = require('../util/launchEditor');
 
-module.exports = function({watchFolders}) {
-  return function(req, res, next) {
+module.exports = function getOpenStackFrameInEditorMiddleware({
+  watchFolders,
+}) {
+  return (req, res, next) => {
     if (req.url === '/open-stack-frame') {
       const frame = JSON.parse(req.rawBody);
       launchEditor(frame.file, frame.lineNumber, watchFolders);
diff --git a/packages/local-cli/server/middleware/statusPageMiddleware.js b/packages/local-cli/server/middleware/statusPageMiddleware.js
index b08539d57..00584ecbb 100644
--- a/packages/local-cli/server/middleware/statusPageMiddleware.js
+++ b/packages/local-cli/server/middleware/statusPageMiddleware.js
@@ -7,13 +7,11 @@
  * @format
  */
 
-'use strict';
-
 /**
  * Status page so that anyone who needs to can verify that the packager is
  * running on 8081 and not another program / service.
  */
-module.exports = function(req, res, next) {
+module.exports = function statusPageMiddleware(req, res, next) {
   if (req.url === '/status') {
     res.end('packager-status:running');
   } else {
diff --git a/packages/local-cli/server/middleware/systraceProfileMiddleware.js b/packages/local-cli/server/middleware/systraceProfileMiddleware.js
index c66d6f7be..24c54024c 100644
--- a/packages/local-cli/server/middleware/systraceProfileMiddleware.js
+++ b/packages/local-cli/server/middleware/systraceProfileMiddleware.js
@@ -7,26 +7,22 @@
  * @format
  */
 
-'use strict';
-
 const fs = require('fs');
 
-module.exports = function(req, res, next) {
+module.exports = function systraceProfileMiddleware(req, res, next) {
   if (req.url !== '/systrace') {
     next();
     return;
   }
 
   console.log('Dumping profile information...');
-  var dumpName = '/tmp/dump_' + Date.now() + '.json';
+  const dumpName = `/tmp/dump_${Date.now()}.json`;
   fs.writeFileSync(dumpName, req.rawBody);
-  var response =
-    'Your profile was saved at:\n' +
-    dumpName +
-    '\n\n' +
-    'On Google Chrome navigate to chrome://tracing and then click on "load" ' +
-    'to load and visualise your profile.\n\n' +
-    'This message is also printed to your console by the packager so you can copy it :)';
+  const response =
+    `Your profile was saved at:\n${dumpName}\n\n` +
+    `On Google Chrome navigate to chrome://tracing and then click on "load" ` +
+    `to load and visualise your profile.\n\n` +
+    `This message is also printed to your console by the packager so you can copy it :)`;
   console.log(response);
   res.end(response);
 };
diff --git a/packages/local-cli/server/middleware/unless.js b/packages/local-cli/server/middleware/unless.js
index e1aa78ac6..9d04f2f2f 100644
--- a/packages/local-cli/server/middleware/unless.js
+++ b/packages/local-cli/server/middleware/unless.js
@@ -7,14 +7,10 @@
  * @format
  */
 
-'use strict';
-
-module.exports = (url, middleware) => {
-  return (req, res, next) => {
-    if (req.url === url || req.url.startsWith(url + '/')) {
-      middleware(req, res, next);
-    } else {
-      next();
-    }
-  };
+module.exports = (url, middleware) => (req, res, next) => {
+  if (req.url === url || req.url.startsWith(`${url}/`)) {
+    middleware(req, res, next);
+  } else {
+    next();
+  }
 };
diff --git a/packages/local-cli/server/runServer.js b/packages/local-cli/server/runServer.js
index 5daaa5204..e3da6e468 100644
--- a/packages/local-cli/server/runServer.js
+++ b/packages/local-cli/server/runServer.js
@@ -4,25 +4,23 @@
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
  *
- * @format
+ * @flow
  */
 
-'use strict';
+import type { ContextT } from '../core/types.flow';
 
 const Metro = require('metro');
 
 const { Terminal } = require('metro-core');
 
-const messageSocket = require('./util/messageSocket');
 const morgan = require('morgan');
 const path = require('path');
+const messageSocket = require('./util/messageSocket');
 const webSocketProxy = require('./util/webSocketProxy');
 const MiddlewareManager = require('./middleware/MiddlewareManager');
 
 const loadMetroConfig = require('../util/loadMetroConfig');
 
-import type { ContextT } from '../core/types.flow';
-
 export type Args = {|
   assetExts?: string[],
   cert?: string,
@@ -57,15 +55,17 @@ async function runServer(argv: *, ctx: ContextT, args: Args) {
     sourceExts: args.sourceExts,
     reporter,
   });
-  
+
   const middlewareManager = new MiddlewareManager({
     host: args.host,
-    watchFolders: metroConfig.watchFolders
+    watchFolders: metroConfig.watchFolders,
   });
 
   middlewareManager.getConnectInstance().use(morgan('combined'));
 
-  metroConfig.watchFolders.forEach(middlewareManager.serveStatic.bind(middlewareManager));
+  metroConfig.watchFolders.forEach(
+    middlewareManager.serveStatic.bind(middlewareManager)
+  );
 
   metroConfig.server.enhanceMiddleware = middleware =>
     middlewareManager.getConnectInstance().use(middleware);
@@ -80,7 +80,7 @@ async function runServer(argv: *, ctx: ContextT, args: Args) {
 
   const wsProxy = webSocketProxy.attachToServer(
     serverInstance,
-    '/debugger-proxy',
+    '/debugger-proxy'
   );
   const ms = messageSocket.attachToServer(serverInstance, '/message');
   middlewareManager.attachDevToolsSocket(wsProxy);
diff --git a/packages/local-cli/server/server.js b/packages/local-cli/server/server.js
index 8a4d950c0..c6eed0d37 100644
--- a/packages/local-cli/server/server.js
+++ b/packages/local-cli/server/server.js
@@ -8,12 +8,8 @@
  * @flow
  */
 
-'use strict';
-
 const path = require('path');
 
-import type { ContextT } from '../core/types.flow';
-
 module.exports = {
   name: 'start',
   func: require('./runServer'),
diff --git a/packages/local-cli/server/util/copyToClipBoard.js b/packages/local-cli/server/util/copyToClipBoard.js
index e6b1bd7a1..ebc728ccc 100644
--- a/packages/local-cli/server/util/copyToClipBoard.js
+++ b/packages/local-cli/server/util/copyToClipBoard.js
@@ -7,32 +7,34 @@
  * @format
  */
 
-'use strict';
+const { spawn } = require('child_process');
 
-var child_process = require('child_process');
-var spawn = child_process.spawn;
-var path = require('path');
-var fs = require('fs');
+const path = require('path');
+const fs = require('fs');
 
 const xsel = path.join(__dirname, 'external/xsel');
 fs.chmodSync(xsel, '0755');
+
 /**
  * Copy the content to host system clipboard.
  */
 function copyToClipBoard(content) {
   switch (process.platform) {
-    case 'darwin':
-      var child = spawn('pbcopy', []);
+    case 'darwin': {
+      const child = spawn('pbcopy', []);
       child.stdin.end(Buffer.from(content, 'utf8'));
       return true;
-    case 'win32':
-      var child = spawn('clip', []);
+    }
+    case 'win32': {
+      const child = spawn('clip', []);
       child.stdin.end(Buffer.from(content, 'utf8'));
       return true;
-    case 'linux':
-      var child = spawn(xsel, ['--clipboard', '--input']);
+    }
+    case 'linux': {
+      const child = spawn(xsel, ['--clipboard', '--input']);
       child.stdin.end(Buffer.from(content, 'utf8'));
       return true;
+    }
     default:
       return false;
   }
diff --git a/packages/local-cli/server/util/jsPackagerClient.js b/packages/local-cli/server/util/jsPackagerClient.js
index 08e6516f5..cf36357e4 100644
--- a/packages/local-cli/server/util/jsPackagerClient.js
+++ b/packages/local-cli/server/util/jsPackagerClient.js
@@ -7,11 +7,9 @@
  * @format
  */
 
-'use strict';
-
 const WebSocket = require('ws');
 
-const parseMessage = require('./messageSocket').parseMessage;
+const { parseMessage } = require('./messageSocket');
 
 const PROTOCOL_VERSION = 2;
 const TARGET_SERVER = 'server';
@@ -37,12 +35,10 @@ class JsPackagerClient {
         // gracefully ignore wrong messages or broadcasts
       } else if (msgCallback === undefined) {
         console.warn(`Response with non-existing message id: '${message.id}'`);
+      } else if (message.error === undefined) {
+        msgCallback.resolve(message.result);
       } else {
-        if (message.error === undefined) {
-          msgCallback.resolve(message.result);
-        } else {
-          msgCallback.reject(message.error);
-        }
+        msgCallback.reject(message.error);
       }
     });
   }
@@ -52,23 +48,23 @@ class JsPackagerClient {
       () =>
         new Promise((resolve, reject) => {
           const messageId = getMessageId();
-          this.msgCallbacks.set(messageId, {resolve: resolve, reject: reject});
+          this.msgCallbacks.set(messageId, { resolve, reject });
           this.ws.send(
             JSON.stringify({
               version: PROTOCOL_VERSION,
-              target: target,
-              method: method,
+              target,
+              method,
               id: messageId,
-              params: params,
+              params,
             }),
             error => {
               if (error !== undefined) {
                 this.msgCallbacks.delete(messageId);
                 reject(error);
               }
-            },
+            }
           );
-        }),
+        })
     );
   }
 
@@ -79,9 +75,9 @@ class JsPackagerClient {
           this.ws.send(
             JSON.stringify({
               version: PROTOCOL_VERSION,
-              target: target,
-              method: method,
-              params: params,
+              target,
+              method,
+              params,
             }),
             error => {
               if (error !== undefined) {
@@ -89,9 +85,9 @@ class JsPackagerClient {
               } else {
                 resolve();
               }
-            },
+            }
           );
-        }),
+        })
     );
   }
 
@@ -102,10 +98,13 @@ class JsPackagerClient {
   getPeers() {
     return new Promise((resolve, reject) => {
       this.sendRequest('getpeers', TARGET_SERVER, undefined).then(response => {
-        if (!response instanceof Map) {
+        if (!(response instanceof Map)) {
           reject(
-            'Results received from server are of wrong format:\n' +
-              JSON.stringify(response),
+            new Error(
+              `Results received from server are of wrong format:\n${JSON.stringify(
+                response
+              )}`
+            )
           );
         } else {
           resolve(response);
diff --git a/packages/local-cli/server/util/launchChrome.js b/packages/local-cli/server/util/launchChrome.js
index 854ae20c8..67c449d2a 100644
--- a/packages/local-cli/server/util/launchChrome.js
+++ b/packages/local-cli/server/util/launchChrome.js
@@ -8,23 +8,17 @@
  * @flow
  */
 
-'use strict';
-
 /* $FlowFixMe(>=0.54.0 site=react_native_oss) This comment suppresses an error
  * found when Flow v0.54 was deployed. To see the error delete this comment and
  * run Flow. */
 const opn = require('opn');
-const execSync = require('child_process').execSync;
+const { execSync } = require('child_process');
 
-function commandExistsUnixSync(commandName, callback) {
+function commandExistsUnixSync(commandName) {
   try {
-    var stdout = execSync(
-      'command -v ' +
-        commandName +
-        ' 2>/dev/null' +
-        " && { echo >&1 '" +
-        commandName +
-        " found'; exit 0; }",
+    const stdout = execSync(
+      `command -v ${commandName} 2>/dev/null` +
+        ` && { echo >&1 '${commandName} found'; exit 0; }`
     );
     return !!stdout;
   } catch (error) {
@@ -41,18 +35,19 @@ function getChromeAppName(): string {
     case 'linux':
       if (commandExistsUnixSync('google-chrome')) {
         return 'google-chrome';
-      } else if (commandExistsUnixSync('chromium-browser')) {
+      }
+      if (commandExistsUnixSync('chromium-browser')) {
         return 'chromium-browser';
-      } else {
-        return 'chromium';
       }
+      return 'chromium';
+
     default:
       return 'google-chrome';
   }
 }
 
 function launchChrome(url: string) {
-  opn(url, {app: [getChromeAppName()]}, function(err) {
+  opn(url, { app: [getChromeAppName()] }, err => {
     if (err) {
       console.error('Google Chrome exited with error:', err);
     }
diff --git a/packages/local-cli/server/util/launchEditor.js b/packages/local-cli/server/util/launchEditor.js
index ac965b085..211d5c80c 100644
--- a/packages/local-cli/server/util/launchEditor.js
+++ b/packages/local-cli/server/util/launchEditor.js
@@ -7,12 +7,10 @@
  * @format
  */
 
-'use strict';
-
-var chalk = require('chalk');
-var fs = require('fs');
-var path = require('path');
-var child_process = require('child_process');
+const chalk = require('chalk');
+const fs = require('fs');
+const path = require('path');
+const { execSync, spawn } = require('child_process');
 const isAbsolutePath = require('absolute-path');
 const shellQuote = require('shell-quote');
 
@@ -22,14 +20,15 @@ function isTerminalEditor(editor) {
     case 'emacs':
     case 'nano':
       return true;
+    default:
+      return false;
   }
-  return false;
 }
 
 // Map from full process name to binary that starts the process
 // We can't just re-use full process name, because it will spawn a new instance
 // of the app every time
-var COMMON_EDITORS = {
+const COMMON_EDITORS = {
   '/Applications/Atom.app/Contents/MacOS/Atom': 'atom',
   '/Applications/Atom Beta.app/Contents/MacOS/Atom Beta':
     '/Applications/Atom Beta.app/Contents/MacOS/Atom Beta',
@@ -58,7 +57,7 @@ function getArgumentsForLineNumber(editor, fileName, lineNumber, workspace) {
   switch (path.basename(editor)) {
     case 'vim':
     case 'mvim':
-      return [fileName, '+' + lineNumber];
+      return [fileName, `+${lineNumber}`];
     case 'atom':
     case 'Atom':
     case 'Atom Beta':
@@ -69,26 +68,26 @@ function getArgumentsForLineNumber(editor, fileName, lineNumber, workspace) {
     case 'appcode':
     case 'charm':
     case 'idea':
-      return [fileName + ':' + lineNumber];
+      return [`${fileName}:${lineNumber}`];
     case 'joe':
     case 'emacs':
     case 'emacsclient':
-      return ['+' + lineNumber, fileName];
+      return [`+${lineNumber}`, fileName];
     case 'rmate':
     case 'mate':
     case 'mine':
       return ['--line', lineNumber, fileName];
     case 'code':
       return addWorkspaceToArgumentsIfExists(
-        ['-g', fileName + ':' + lineNumber],
-        workspace,
+        ['-g', `${fileName}:${lineNumber}`],
+        workspace
       );
+    // For all others, drop the lineNumber until we have
+    // a mapping above, since providing the lineNumber incorrectly
+    // can result in errors or confusing behavior.
+    default:
+      return [fileName];
   }
-
-  // For all others, drop the lineNumber until we have
-  // a mapping above, since providing the lineNumber incorrectly
-  // can result in errors or confusing behavior.
-  return [fileName];
 }
 
 function guessEditor() {
@@ -101,10 +100,10 @@ function guessEditor() {
   // Potentially we could use similar technique for Windows and Linux
   if (process.platform === 'darwin') {
     try {
-      var output = child_process.execSync('ps x').toString();
-      var processNames = Object.keys(COMMON_EDITORS);
-      for (var i = 0; i < processNames.length; i++) {
-        var processName = processNames[i];
+      const output = execSync('ps x').toString();
+      const processNames = Object.keys(COMMON_EDITORS);
+      for (let i = 0; i < processNames.length; i++) {
+        const processName = processNames[i];
         if (output.indexOf(processName) !== -1) {
           return [COMMON_EDITORS[processName]];
         }
@@ -117,7 +116,8 @@ function guessEditor() {
   // Last resort, use old skool env vars
   if (process.env.VISUAL) {
     return [process.env.VISUAL];
-  } else if (process.env.EDITOR) {
+  }
+  if (process.env.EDITOR) {
     return [process.env.EDITOR];
   }
 
@@ -128,7 +128,7 @@ function printInstructions(title) {
   console.log(
     [
       '',
-      chalk.bgBlue.white.bold(' ' + title + ' '),
+      chalk.bgBlue.white.bold(` ${title} `),
       '  When you see Red Box with stack trace, you can click any ',
       '  stack frame to jump to the source file. The packager will launch your ',
       '  editor of choice. It will first look at REACT_EDITOR environment ',
@@ -136,26 +136,26 @@ function printInstructions(title) {
       '  export REACT_EDITOR=atom to your ~/.bashrc or ~/.zshrc depending on ',
       '  which shell you use.',
       '',
-    ].join('\n'),
+    ].join('\n')
   );
 }
 
 function transformToAbsolutePathIfNeeded(pathName) {
   if (!isAbsolutePath(pathName)) {
-    pathName = path.resolve(process.cwd(), pathName);
+    return path.resolve(process.cwd(), pathName);
   }
   return pathName;
 }
 
 function findRootForFile(projectRoots, fileName) {
-  fileName = transformToAbsolutePathIfNeeded(fileName);
+  const absoluteFileName = transformToAbsolutePathIfNeeded(fileName);
   return projectRoots.find(root => {
-    root = transformToAbsolutePathIfNeeded(root);
-    return fileName.startsWith(root + path.sep);
+    const absoluteRoot = transformToAbsolutePathIfNeeded(root);
+    return absoluteFileName.startsWith(absoluteRoot + path.sep);
   });
 }
 
-var _childProcess = null;
+let _childProcess = null;
 function launchEditor(fileName, lineNumber, projectRoots) {
   if (!fs.existsSync(fileName)) {
     return;
@@ -167,16 +167,16 @@ function launchEditor(fileName, lineNumber, projectRoots) {
     return;
   }
 
-  let [editor, ...args] = guessEditor();
+  let [editor, ...args] = guessEditor(); // eslint-disable-line prefer-const
   if (!editor) {
     printInstructions('PRO TIP');
     return;
   }
 
-  var workspace = findRootForFile(projectRoots, fileName);
+  const workspace = findRootForFile(projectRoots, fileName);
   if (lineNumber) {
     args = args.concat(
-      getArgumentsForLineNumber(editor, fileName, lineNumber, workspace),
+      getArgumentsForLineNumber(editor, fileName, lineNumber, workspace)
     );
   } else {
     args.push(fileName);
@@ -192,23 +192,21 @@ function launchEditor(fileName, lineNumber, projectRoots) {
   ) {
     console.log();
     console.log(
-      chalk.red(
-        'Could not open ' + path.basename(fileName) + ' in the editor.',
-      ),
+      chalk.red(`Could not open ${path.basename(fileName)} in the editor.`)
     );
     console.log();
     console.log(
       'When running on Windows, file names are checked against a whitelist ' +
         'to protect against remote code execution attacks. File names may ' +
         'consist only of alphanumeric characters (all languages), periods, ' +
-        'dashes, slashes, and underscores.',
+        'dashes, slashes, and underscores.'
     );
     console.log();
     return;
   }
 
   console.log(
-    'Opening ' + chalk.underline(fileName) + ' with ' + chalk.bold(editor),
+    `Opening ${chalk.underline(fileName)} with ${chalk.bold(editor)}`
   );
 
   if (_childProcess && isTerminalEditor(editor)) {
@@ -221,15 +219,13 @@ function launchEditor(fileName, lineNumber, projectRoots) {
   if (process.platform === 'win32') {
     // On Windows, launch the editor in a shell because spawn can only
     // launch .exe files.
-    _childProcess = child_process.spawn(
-      'cmd.exe',
-      ['/C', editor].concat(args),
-      {stdio: 'inherit'},
-    );
+    _childProcess = spawn('cmd.exe', ['/C', editor].concat(args), {
+      stdio: 'inherit',
+    });
   } else {
-    _childProcess = child_process.spawn(editor, args, {stdio: 'inherit'});
+    _childProcess = spawn(editor, args, { stdio: 'inherit' });
   }
-  _childProcess.on('exit', function(errorCode) {
+  _childProcess.on('exit', errorCode => {
     _childProcess = null;
 
     if (errorCode) {
@@ -238,7 +234,7 @@ function launchEditor(fileName, lineNumber, projectRoots) {
     }
   });
 
-  _childProcess.on('error', function(error) {
+  _childProcess.on('error', error => {
     console.log(chalk.red(error.message));
     printInstructions('How to fix:');
   });
diff --git a/packages/local-cli/server/util/messageSocket.js b/packages/local-cli/server/util/messageSocket.js
index a151f7916..30b02da90 100644
--- a/packages/local-cli/server/util/messageSocket.js
+++ b/packages/local-cli/server/util/messageSocket.js
@@ -3,14 +3,11 @@
  *
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
- *
- * @format
  */
 
-'use strict';
-
 const url = require('url');
 const WebSocketServer = require('ws').Server;
+
 const PROTOCOL_VERSION = 2;
 const notifier = require('node-notifier');
 
@@ -25,10 +22,10 @@ function parseMessage(data, binary) {
       return message;
     }
     console.error(
-      'Received message had wrong protocol version: ' + message.version,
+      `Received message had wrong protocol version: ${message.version}`
     );
   } catch (e) {
-    console.error('Failed to parse the message as JSON:\n' + data);
+    console.error(`Failed to parse the message as JSON:\n${data}`);
   }
   return undefined;
 }
@@ -50,7 +47,7 @@ function isRequest(message) {
 function isResponse(message) {
   return (
     typeof message.id === 'object' &&
-    typeof message.id.requestId !== undefined &&
+    typeof message.id.requestId !== 'undefined' &&
     typeof message.id.clientId === 'string' &&
     (message.result !== undefined || message.error !== undefined)
   );
@@ -58,8 +55,8 @@ function isResponse(message) {
 
 function attachToServer(server, path) {
   const wss = new WebSocketServer({
-    server: server,
-    path: path,
+    server,
+    path,
   });
   const clients = new Map();
   let nextClientId = 0;
@@ -67,7 +64,9 @@ function attachToServer(server, path) {
   function getClientWs(clientId) {
     const clientWs = clients.get(clientId);
     if (clientWs === undefined) {
-      throw `could not find id "${clientId}" while forwarding request`;
+      throw new Error(
+        `could not find id "${clientId}" while forwarding request`
+      );
     }
     return clientWs;
   }
@@ -94,14 +93,14 @@ function attachToServer(server, path) {
         } catch (e) {
           console.error(
             `Failed to send broadcast to client: '${otherId}' ` +
-              `due to:\n ${e.toString()}`,
+              `due to:\n ${e.toString()}`
           );
         }
       }
     }
   }
 
-  wss.on('connection', function(clientWs) {
+  wss.on('connection', clientWs => {
     const clientId = `client#${nextClientId++}`;
 
     function handleCaughtError(message, error) {
@@ -117,22 +116,22 @@ function attachToServer(server, path) {
       if (message.id === undefined) {
         console.error(
           `Handling message from ${clientId} failed with:\n${error}\n` +
-            `message:\n${JSON.stringify(errorMessage)}`,
+            `message:\n${JSON.stringify(errorMessage)}`
         );
       } else {
         try {
           clientWs.send(
             JSON.stringify({
               version: PROTOCOL_VERSION,
-              error: error,
+              error,
               id: message.id,
-            }),
+            })
           );
         } catch (e) {
           console.error(
             `Failed to reply to ${clientId} with error:\n${error}` +
               `\nmessage:\n${JSON.stringify(errorMessage)}` +
-              `\ndue to error: ${e.toString()}`,
+              `\ndue to error: ${e.toString()}`
           );
         }
       }
@@ -153,15 +152,15 @@ function attachToServer(server, path) {
           });
           break;
         default:
-          throw `unknown method: ${message.method}`;
+          throw new Error(`unknown method: ${message.method}`);
       }
 
       clientWs.send(
         JSON.stringify({
           version: PROTOCOL_VERSION,
-          result: result,
+          result,
           id: message.id,
-        }),
+        })
       );
     }
 
@@ -174,8 +173,8 @@ function attachToServer(server, path) {
           id:
             message.id === undefined
               ? undefined
-              : {requestId: message.id, clientId: clientId},
-        }),
+              : { requestId: message.id, clientId },
+        })
       );
     }
 
@@ -186,15 +185,18 @@ function attachToServer(server, path) {
           result: message.result,
           error: message.error,
           id: message.id.requestId,
-        }),
+        })
       );
     }
 
     clients.set(clientId, clientWs);
-    clientWs.onclose = clientWs.onerror = () => {
-      clientWs.onmessage = null;
+    const onCloseHandler = () => {
+      clientWs.onmessage = null; // eslint-disable-line no-param-reassign
       clients.delete(clientId);
     };
+    clientWs.onclose = onCloseHandler; // eslint-disable-line no-param-reassign
+    clientWs.onerror = onCloseHandler; // eslint-disable-line no-param-reassign
+    // eslint-disable-next-line no-param-reassign
     clientWs.onmessage = event => {
       const message = parseMessage(event.data, event.binary);
       if (message === undefined) {
@@ -214,7 +216,7 @@ function attachToServer(server, path) {
         } else if (isResponse(message)) {
           forwardResponse(message);
         } else {
-          throw 'Invalid message, did not match the protocol';
+          throw new Error('Invalid message, did not match the protocol');
         }
       } catch (e) {
         handleCaughtError(message, e.toString());
@@ -224,12 +226,12 @@ function attachToServer(server, path) {
 
   return {
     broadcast: (method, params) => {
-      handleSendBroadcast(null, {method: method, params: params});
+      handleSendBroadcast(null, { method, params });
     },
   };
 }
 
 module.exports = {
-  attachToServer: attachToServer,
-  parseMessage: parseMessage,
+  attachToServer,
+  parseMessage,
 };
diff --git a/packages/local-cli/server/util/webSocketProxy.js b/packages/local-cli/server/util/webSocketProxy.js
index 097a5de53..a7d0c8a9d 100644
--- a/packages/local-cli/server/util/webSocketProxy.js
+++ b/packages/local-cli/server/util/webSocketProxy.js
@@ -7,15 +7,15 @@
  * @format
  */
 
-'use strict';
-
 function attachToServer(server, path) {
-  var WebSocketServer = require('ws').Server;
-  var wss = new WebSocketServer({
-    server: server,
-    path: path,
+  const WebSocketServer = require('ws').Server;
+  const wss = new WebSocketServer({
+    server,
+    path,
   });
-  var debuggerSocket, clientSocket;
+
+  let debuggerSocket;
+  let clientSocket;
 
   function send(dest, message) {
     if (!dest) {
@@ -30,8 +30,20 @@ function attachToServer(server, path) {
     }
   }
 
-  wss.on('connection', function(ws) {
-    const {url} = ws.upgradeReq;
+  const debuggerSocketCloseHandler = () => {
+    debuggerSocket = null;
+    if (clientSocket) {
+      clientSocket.close(1011, 'Debugger was disconnected');
+    }
+  };
+
+  const clientSocketCloseHandler = () => {
+    clientSocket = null;
+    send(debuggerSocket, JSON.stringify({ method: '$disconnected' }));
+  };
+
+  wss.on('connection', ws => {
+    const { url } = ws.upgradeReq;
 
     if (url.indexOf('role=debugger') > -1) {
       if (debuggerSocket) {
@@ -39,24 +51,20 @@ function attachToServer(server, path) {
         return;
       }
       debuggerSocket = ws;
-      debuggerSocket.onerror = debuggerSocket.onclose = () => {
-        debuggerSocket = null;
-        if (clientSocket) {
-          clientSocket.close(1011, 'Debugger was disconnected');
-        }
-      };
-      debuggerSocket.onmessage = ({data}) => send(clientSocket, data);
+      debuggerSocket.onerror = debuggerSocketCloseHandler;
+      debuggerSocket.onclose = debuggerSocketCloseHandler;
+      debuggerSocket.onmessage = ({ data }) => send(clientSocket, data);
     } else if (url.indexOf('role=client') > -1) {
       if (clientSocket) {
-        clientSocket.onerror = clientSocket.onclose = clientSocket.onmessage = null;
+        clientSocket.onerror = null;
+        clientSocket.onclose = null;
+        clientSocket.onmessage = null;
         clientSocket.close(1011, 'Another client connected');
       }
       clientSocket = ws;
-      clientSocket.onerror = clientSocket.onclose = () => {
-        clientSocket = null;
-        send(debuggerSocket, JSON.stringify({method: '$disconnected'}));
-      };
-      clientSocket.onmessage = ({data}) => send(debuggerSocket, data);
+      clientSocket.onerror = clientSocketCloseHandler;
+      clientSocket.onclose = clientSocketCloseHandler;
+      clientSocket.onmessage = ({ data }) => send(debuggerSocket, data);
     } else {
       ws.close(1011, 'Missing role param');
     }
@@ -64,12 +72,12 @@ function attachToServer(server, path) {
 
   return {
     server: wss,
-    isChromeConnected: function() {
+    isChromeConnected() {
       return !!debuggerSocket;
     },
   };
 }
 
 module.exports = {
-  attachToServer: attachToServer,
+  attachToServer,
 };
diff --git a/packages/local-cli/templates/HelloWorld/App.js b/packages/local-cli/templates/HelloWorld/App.js
index bb4823295..dd74fbabe 100644
--- a/packages/local-cli/templates/HelloWorld/App.js
+++ b/packages/local-cli/templates/HelloWorld/App.js
@@ -7,8 +7,8 @@
  * @lint-ignore-every XPLATJSCOPYRIGHT1
  */
 
-import React, {Component} from 'react';
-import {Platform, StyleSheet, Text, View} from 'react-native';
+import React, { Component } from 'react';
+import { Platform, StyleSheet, Text, View } from 'react-native';
 
 const instructions = Platform.select({
   ios: 'Press Cmd+R to reload,\n' + 'Cmd+D or shake for dev menu',
diff --git a/packages/local-cli/templates/HelloWorld/__tests__/App-test.js b/packages/local-cli/templates/HelloWorld/__tests__/App-test.js
index a79ec3d58..cde09261e 100644
--- a/packages/local-cli/templates/HelloWorld/__tests__/App-test.js
+++ b/packages/local-cli/templates/HelloWorld/__tests__/App-test.js
@@ -5,10 +5,10 @@
 
 import 'react-native';
 import React from 'react';
+import renderer from 'react-test-renderer';
 import App from '../App';
 
 // Note: test renderer must be required after react-native.
-import renderer from 'react-test-renderer';
 
 it('renders correctly', () => {
   renderer.create(<App />);
diff --git a/packages/local-cli/templates/HelloWorld/index.js b/packages/local-cli/templates/HelloWorld/index.js
index 3ac66525d..ad1dc02b6 100644
--- a/packages/local-cli/templates/HelloWorld/index.js
+++ b/packages/local-cli/templates/HelloWorld/index.js
@@ -3,8 +3,8 @@
  * @lint-ignore-every XPLATJSCOPYRIGHT1
  */
 
-import {AppRegistry} from 'react-native';
+import { AppRegistry } from 'react-native';
 import App from './App';
-import {name as appName} from './app.json';
+import { name as appName } from './app.json';
 
 AppRegistry.registerComponent(appName, () => App);
diff --git a/packages/local-cli/upgrade/upgrade.js b/packages/local-cli/upgrade/upgrade.js
index 202afe52c..fdaad1b04 100644
--- a/packages/local-cli/upgrade/upgrade.js
+++ b/packages/local-cli/upgrade/upgrade.js
@@ -7,13 +7,11 @@
  * @format
  */
 
-'use strict';
-
 const chalk = require('chalk');
-const copyProjectTemplateAndReplace = require('../generator/copyProjectTemplateAndReplace');
 const fs = require('fs');
 const path = require('path');
 const semver = require('semver');
+const copyProjectTemplateAndReplace = require('../generator/copyProjectTemplateAndReplace');
 
 /**
  * Migrate application to a new version of React Native.
@@ -28,7 +26,7 @@ function validateAndUpgrade() {
   const projectDir = process.cwd();
 
   const packageJSON = JSON.parse(
-    fs.readFileSync(path.resolve(projectDir, 'package.json'), 'utf8'),
+    fs.readFileSync(path.resolve(projectDir, 'package.json'), 'utf8')
   );
 
   warn(
@@ -38,14 +36,14 @@ function validateAndUpgrade() {
       '- Go back to the old version of React Native\n' +
       '- Run "npm install -g react-native-git-upgrade"\n' +
       '- Run "react-native-git-upgrade"\n' +
-      'See https://facebook.github.io/react-native/docs/upgrading.html',
+      'See https://facebook.github.io/react-native/docs/upgrading.html'
   );
 
   const projectName = packageJSON.name;
   if (!projectName) {
     warn(
       'Your project needs to have a name, declared in package.json, ' +
-        'such as "name": "AwesomeApp". Please add a project name. Aborting.',
+        'such as "name": "AwesomeApp". Please add a project name. Aborting.'
     );
     return;
   }
@@ -54,7 +52,7 @@ function validateAndUpgrade() {
   if (!version) {
     warn(
       'Your "package.json" file doesn\'t seem to declare "react-native" as ' +
-        'a dependency. Nothing to upgrade. Aborting.',
+        'a dependency. Nothing to upgrade. Aborting.'
     );
     return;
   }
@@ -63,7 +61,7 @@ function validateAndUpgrade() {
     warn(
       'Some major releases introduce breaking changes.\n' +
         'Please use a caret version number in your "package.json" file \n' +
-        'to avoid breakage. Use e.g. react-native: ^0.38.0. Aborting.',
+        'to avoid breakage. Use e.g. react-native: ^0.38.0. Aborting.'
     );
     return;
   }
@@ -71,15 +69,15 @@ function validateAndUpgrade() {
   const installed = JSON.parse(
     fs.readFileSync(
       path.resolve(projectDir, 'node_modules/react-native/package.json'),
-      'utf8',
-    ),
+      'utf8'
+    )
   );
 
   if (!semver.satisfies(installed.version, version)) {
     warn(
       'react-native version in "package.json" doesn\'t match ' +
         'the installed version in "node_modules".\n' +
-        'Try running "npm install" to fix this. Aborting.',
+        'Try running "npm install" to fix this. Aborting.'
     );
     return;
   }
@@ -89,21 +87,17 @@ function validateAndUpgrade() {
   if (!semver.valid(v)) {
     warn(
       "A valid version number for 'react-native' is not specified in your " +
-        "'package.json' file. Aborting.",
+        "'package.json' file. Aborting."
     );
     return;
   }
 
   console.log(
-    'Upgrading project to react-native v' +
-      installed.version +
-      '\n' +
-      'Check out the release notes and breaking changes: ' +
-      'https://github.com/facebook/react-native/releases/tag/v' +
-      semver.major(v) +
-      '.' +
-      semver.minor(v) +
-      '.0',
+    `Upgrading project to react-native v${installed.version}\n` +
+      `Check out the release notes and breaking changes: ` +
+      `https://github.com/facebook/react-native/releases/tag/v${semver.major(
+        v
+      )}.${semver.minor(v)}.0`
   );
 
   // >= v0.21.0, we require react to be a peer dependency
@@ -112,7 +106,7 @@ function validateAndUpgrade() {
       'Your "package.json" file doesn\'t seem to have "react" as a dependency.\n' +
         '"react" was changed from a dependency to a peer dependency in react-native v0.21.0.\n' +
         'Therefore, it\'s necessary to include "react" in your project\'s dependencies.\n' +
-        'Please run "npm install --save react", then re-run "react-native upgrade".\n',
+        'Please run "npm install --save react", then re-run "react-native upgrade".\n'
     );
     return;
   }
@@ -124,18 +118,15 @@ function validateAndUpgrade() {
         'to do it automatically.\n' +
         'Just run:\n' +
         '"npm install -g rnpm && npm install rnpm-plugin-upgrade@0.26 --save-dev", ' +
-        'then run "rnpm upgrade".',
+        'then run "rnpm upgrade".'
     );
   }
 
-  return new Promise(resolve => {
-    upgradeProjectFiles(projectDir, projectName);
-    console.log(
-      'Successfully upgraded this project to react-native v' +
-        installed.version,
-    );
-    resolve();
-  });
+  upgradeProjectFiles(projectDir, projectName);
+
+  console.log(
+    `Successfully upgraded this project to react-native v${installed.version}`
+  );
 }
 
 /**
@@ -149,11 +140,11 @@ function upgradeProjectFiles(projectDir, projectName) {
       'react-native',
       'local-cli',
       'templates',
-      'HelloWorld',
+      'HelloWorld'
     ),
     projectDir,
     projectName,
-    {upgrade: true},
+    { upgrade: true }
   );
 }
 
diff --git a/packages/local-cli/util/PackageManager.js b/packages/local-cli/util/PackageManager.js
index fe0783ec7..d6e9cda86 100644
--- a/packages/local-cli/util/PackageManager.js
+++ b/packages/local-cli/util/PackageManager.js
@@ -7,10 +7,9 @@
  * @format
  */
 
-'use strict';
-
-const spawnSync = require('child_process').spawnSync;
+const { spawnSync } = require('child_process');
 const yarn = require('../util/yarn');
+
 const spawnOpts = {
   stdio: 'inherit',
   stdin: 'inherit',
@@ -52,7 +51,7 @@ function callYarnOrNpm(yarnCommand, npmCommand) {
 function add(packageName) {
   return callYarnOrNpm(
     `yarn add ${packageName}`,
-    `npm install ${packageName} --save`,
+    `npm install ${packageName} --save`
   );
 }
 
@@ -64,11 +63,11 @@ function add(packageName) {
 function remove(packageName) {
   return callYarnOrNpm(
     `yarn remove ${packageName}`,
-    `npm uninstall --save ${packageName}`,
+    `npm uninstall --save ${packageName}`
   );
 }
 
 module.exports = {
-  add: add,
-  remove: remove,
+  add,
+  remove,
 };
diff --git a/packages/local-cli/util/__mocks__/log.js b/packages/local-cli/util/__mocks__/log.js
index 330cae48f..33dbe25a2 100644
--- a/packages/local-cli/util/__mocks__/log.js
+++ b/packages/local-cli/util/__mocks__/log.js
@@ -7,7 +7,5 @@
  * @format
  */
 
-'use strict';
-
 module.exports.out = () => jest.fn();
 module.exports.err = () => jest.fn();
diff --git a/packages/local-cli/util/assertRequiredOptions.js b/packages/local-cli/util/assertRequiredOptions.js
index 379ad1fc1..bddd4ebe3 100644
--- a/packages/local-cli/util/assertRequiredOptions.js
+++ b/packages/local-cli/util/assertRequiredOptions.js
@@ -7,10 +7,8 @@
  * @format
  */
 
-'use strict';
-
-const {Option} = require('commander');
-const {camelCase} = require('lodash');
+const { Option } = require('commander');
+const { camelCase } = require('lodash');
 
 // Commander.js has a 2 years old open issue to support <...> syntax
 // for options. Until that gets merged, we run the checks manually
diff --git a/packages/local-cli/util/copyAndReplace.js b/packages/local-cli/util/copyAndReplace.js
index d0d4eb15a..67ade61c8 100644
--- a/packages/local-cli/util/copyAndReplace.js
+++ b/packages/local-cli/util/copyAndReplace.js
@@ -7,8 +7,6 @@
  * @format
  */
 
-'use strict';
-
 const fs = require('fs');
 const path = require('path');
 
@@ -31,7 +29,7 @@ function copyAndReplace(
   srcPath,
   destPath,
   replacements,
-  contentChangedCallback,
+  contentChangedCallback
 ) {
   if (fs.lstatSync(srcPath).isDirectory()) {
     if (!fs.existsSync(destPath)) {
@@ -73,13 +71,9 @@ function copyAndReplace(
     // Text file
     const srcPermissions = fs.statSync(srcPath).mode;
     let content = fs.readFileSync(srcPath, 'utf8');
-    Object.keys(replacements).forEach(
-      regex =>
-        (content = content.replace(
-          new RegExp(regex, 'g'),
-          replacements[regex],
-        )),
-    );
+    Object.keys(replacements).forEach(regex => {
+      content = content.replace(new RegExp(regex, 'g'), replacements[regex]);
+    });
 
     let shouldOverwrite = 'overwrite';
     if (contentChangedCallback) {
@@ -88,7 +82,7 @@ function copyAndReplace(
       try {
         const origContent = fs.readFileSync(destPath, 'utf8');
         if (content !== origContent) {
-          //console.log('Content changed: ' + destPath);
+          // console.log('Content changed: ' + destPath);
           contentChanged = 'changed';
         }
       } catch (err) {
@@ -116,16 +110,16 @@ function copyBinaryFile(srcPath, destPath, cb) {
   let cbCalled = false;
   const srcPermissions = fs.statSync(srcPath).mode;
   const readStream = fs.createReadStream(srcPath);
-  readStream.on('error', function(err) {
+  readStream.on('error', err => {
     done(err);
   });
   const writeStream = fs.createWriteStream(destPath, {
     mode: srcPermissions,
   });
-  writeStream.on('error', function(err) {
+  writeStream.on('error', err => {
     done(err);
   });
-  writeStream.on('close', function(ex) {
+  writeStream.on('close', () => {
     done();
   });
   readStream.pipe(writeStream);
diff --git a/packages/local-cli/util/findReactNativeScripts.js b/packages/local-cli/util/findReactNativeScripts.js
index 5d43e2948..0bacfc209 100644
--- a/packages/local-cli/util/findReactNativeScripts.js
+++ b/packages/local-cli/util/findReactNativeScripts.js
@@ -8,8 +8,6 @@
  * @flow strict
  */
 
-'use strict';
-
 const path = require('path');
 const fs = require('fs');
 
@@ -17,7 +15,7 @@ function findReactNativeScripts(): ?string {
   const executablePath = path.resolve(
     'node_modules',
     '.bin',
-    'react-native-scripts',
+    'react-native-scripts'
   );
   if (fs.existsSync(executablePath)) {
     return executablePath;
diff --git a/packages/local-cli/util/findSymlinkedModules.js b/packages/local-cli/util/findSymlinkedModules.js
index a88b41f08..c64b65d7f 100644
--- a/packages/local-cli/util/findSymlinkedModules.js
+++ b/packages/local-cli/util/findSymlinkedModules.js
@@ -32,7 +32,7 @@ const fs = require('fs');
  */
 module.exports = function findSymlinkedModules(
   projectRoot: string,
-  ignoredRoots?: Array<string> = [],
+  ignoredRoots?: Array<string> = []
 ) {
   const nodeModuleRoot = path.join(projectRoot, 'node_modules');
   const resolvedSymlinks = findModuleSymlinks(nodeModuleRoot, [
@@ -44,7 +44,7 @@ module.exports = function findSymlinkedModules(
 
 function findModuleSymlinks(
   modulesPath: string,
-  ignoredPaths: Array<string> = [],
+  ignoredPaths: Array<string> = []
 ): Array<string> {
   if (!fs.existsSync(modulesPath)) {
     return [];
@@ -58,7 +58,7 @@ function findModuleSymlinks(
     if (folderName.startsWith('@')) {
       const scopedModuleFolders = fs.readdirSync(folderPath);
       maybeSymlinkPaths.push(
-        ...scopedModuleFolders.map(name => path.join(folderPath, name)),
+        ...scopedModuleFolders.map(name => path.join(folderPath, name))
       );
     } else {
       maybeSymlinkPaths.push(folderPath);
@@ -76,9 +76,9 @@ function findModuleSymlinks(
         findModuleSymlinks(path.join(symlinkPath, 'node_modules'), [
           ...ignoredPaths,
           ...symlinks,
-        ]),
+        ])
       ),
-    [],
+    []
   );
 
   return [...new Set([...symlinks, ...nestedSymlinks])];
@@ -89,7 +89,7 @@ function resolveSymlinkPaths(maybeSymlinkPaths, ignoredPaths) {
     if (fs.lstatSync(maybeSymlinkPath).isSymbolicLink()) {
       const resolved = path.resolve(
         path.dirname(maybeSymlinkPath),
-        fs.readlinkSync(maybeSymlinkPath),
+        fs.readlinkSync(maybeSymlinkPath)
       );
       if (ignoredPaths.indexOf(resolved) === -1 && fs.existsSync(resolved)) {
         links.push(resolved);
diff --git a/packages/local-cli/util/findSymlinksPaths.js b/packages/local-cli/util/findSymlinksPaths.js
deleted file mode 100644
index 5efa20e88..000000000
--- a/packages/local-cli/util/findSymlinksPaths.js
+++ /dev/null
@@ -1,60 +0,0 @@
-/**
- * Copyright (c) Facebook, Inc. and its affiliates.
- *
- * This source code is licensed under the MIT license found in the
- * LICENSE file in the root directory of this source tree.
- *
- * @format
- */
-
-const path = require('path');
-const fs = require('fs');
-
-/**
- * Find and resolve symlinks in `lookupFolder`.
- * Ignore any descendants of the paths in `ignoredRoots`.
- */
-module.exports = function findSymlinksPaths(lookupFolder, ignoredRoots) {
-  const timeStart = Date.now();
-  const folders = fs.readdirSync(lookupFolder);
-
-  const resolvedSymlinks = [];
-  folders.forEach(folder => {
-    const visited = [];
-
-    let symlink = path.resolve(lookupFolder, folder);
-    while (fs.lstatSync(symlink).isSymbolicLink()) {
-      const index = visited.indexOf(symlink);
-      if (index !== -1) {
-        throw Error(
-          'Infinite symlink recursion detected:\n  ' +
-            visited.slice(index).join('\n  '),
-        );
-      }
-
-      visited.push(symlink);
-      symlink = path.resolve(path.dirname(symlink), fs.readlinkSync(symlink));
-    }
-
-    if (visited.length && !rootExists(ignoredRoots, symlink)) {
-      resolvedSymlinks.push(symlink);
-    }
-  });
-
-  const timeEnd = Date.now();
-  console.log(
-    `Scanning ${
-      folders.length
-    } folders for symlinks in ${lookupFolder} (${timeEnd - timeStart}ms)`,
-  );
-
-  return resolvedSymlinks;
-};
-
-function rootExists(roots, child) {
-  return roots.some(root => isDescendant(root, child));
-}
-
-function isDescendant(root, child) {
-  return root === child || child.startsWith(root + path.sep);
-}
diff --git a/packages/local-cli/util/isInstalledGlobally.js b/packages/local-cli/util/isInstalledGlobally.js
index c817a0812..ac17baaad 100644
--- a/packages/local-cli/util/isInstalledGlobally.js
+++ b/packages/local-cli/util/isInstalledGlobally.js
@@ -15,11 +15,10 @@ module.exports = function isInstalledGlobally() {
     const path = require('path');
     // On Windows, assume we are installed globally if we can't find a
     // package.json above node_modules.
-    return !fs.existsSync(path.join(__dirname, '../../../package.json'), );
-  } else {
-    // On non-windows, assume we are installed globally if we are called from
-    // outside of the node_mobules/.bin/react-native executable.
-    var script = process.argv[1];
-    return script.indexOf('node_modules/.bin/react-native') === -1;
+    return !fs.existsSync(path.join(__dirname, '../../../package.json'));
   }
+  // On non-windows, assume we are installed globally if we are called from
+  // outside of the node_mobules/.bin/react-native executable.
+  const script = process.argv[1];
+  return script.indexOf('node_modules/.bin/react-native') === -1;
 };
diff --git a/packages/local-cli/util/isPackagerRunning.js b/packages/local-cli/util/isPackagerRunning.js
index f8c33e584..57d2be844 100644
--- a/packages/local-cli/util/isPackagerRunning.js
+++ b/packages/local-cli/util/isPackagerRunning.js
@@ -7,8 +7,6 @@
  * @format
  */
 
-'use strict';
-
 const fetch = require('node-fetch');
 
 /**
@@ -25,11 +23,10 @@ function isPackagerRunning(packagerPort = process.env.RCT_METRO_PORT || 8081) {
     res =>
       res
         .text()
-        .then(
-          body =>
-            body === 'packager-status:running' ? 'running' : 'unrecognized',
+        .then(body =>
+          body === 'packager-status:running' ? 'running' : 'unrecognized'
         ),
-    () => 'not_running',
+    () => 'not_running'
   );
 }
 
diff --git a/packages/local-cli/util/isValidPackageName.js b/packages/local-cli/util/isValidPackageName.js
index 45a02319c..03f9fbf26 100644
--- a/packages/local-cli/util/isValidPackageName.js
+++ b/packages/local-cli/util/isValidPackageName.js
@@ -7,8 +7,6 @@
  * @format
  */
 
-'use strict';
-
 function isValidPackageName(name) {
   return name.match(/^[$A-Z_][0-9A-Z_$]*$/i);
 }
diff --git a/packages/local-cli/util/loadMetroConfig.js b/packages/local-cli/util/loadMetroConfig.js
index 8bb68c843..275b6694a 100644
--- a/packages/local-cli/util/loadMetroConfig.js
+++ b/packages/local-cli/util/loadMetroConfig.js
@@ -1,25 +1,24 @@
 /**
  * @flow
  */
-'use strict';
+/* eslint-disable no-param-reassign */
+/**
+ * Configuration file of Metro.
+ */
+import type { ConfigT } from 'metro-config/src/configTypes.flow';
 
-const findSymlinkedModules = require('./findSymlinkedModules');
 const path = require('path');
 
-const {createBlacklist} = require('metro');
-const {loadConfig} = require('metro-config');
+const { createBlacklist } = require('metro');
+const { loadConfig } = require('metro-config');
+const findSymlinkedModules = require('./findSymlinkedModules');
 
 const findPlugins = require('../core/findPlugins');
 
-/**
- * Configuration file of Metro.
- */
-import type {ConfigT} from 'metro-config/src/configTypes.flow';
-
-const resolveSymlinksForRoots = (roots) =>
+const resolveSymlinksForRoots = roots =>
   roots.reduce<string[]>(
     (arr, rootPath) => arr.concat(findSymlinkedModules(rootPath, roots)),
-    [...roots],
+    [...roots]
   );
 
 const getWatchFolders = () => {
@@ -30,26 +29,27 @@ const getWatchFolders = () => {
   return [];
 };
 
-const getBlacklistRE = () => {
-  return createBlacklist([/.*\/__fixtures__\/.*/]);
-};
+const getBlacklistRE = () => createBlacklist([/.*\/__fixtures__\/.*/]);
 
 /**
  * Default configuration
- * 
+ *
  * @todo(grabbou): As a separate PR, haste.platforms should be added before "native".
  * Otherwise, a.native.js will not load on Windows or other platforms
  */
 const getDefaultConfig = (root: string) => {
   const plugins = findPlugins(root);
 
-  return ({
+  return {
     resolver: {
       resolverMainFields: ['react-native', 'browser', 'main'],
       blacklistRE: getBlacklistRE(),
       platforms: ['ios', 'android', 'native', ...plugins.haste.platforms],
-      providesModuleNodeModules: ['react-native', ...plugins.haste.providesModuleNodeModules],
-      hasteImplModulePath: require.resolve('react-native/jest/hasteImpl')
+      providesModuleNodeModules: [
+        'react-native',
+        ...plugins.haste.providesModuleNodeModules,
+      ],
+      hasteImplModulePath: require.resolve('react-native/jest/hasteImpl'),
     },
     serializer: {
       getModulesRunBeforeMainModule: () => [
@@ -62,10 +62,12 @@ const getDefaultConfig = (root: string) => {
     },
     transformer: {
       babelTransformerPath: require.resolve('metro/src/reactNativeTransformer'),
-      assetRegistryPath: require.resolve('react-native/Libraries/Image/AssetRegistry')
+      assetRegistryPath: require.resolve(
+        'react-native/Libraries/Image/AssetRegistry'
+      ),
     },
     watchFolders: getWatchFolders(),
-  });
+  };
 };
 
 export type ConfigOptionsT = {
@@ -74,13 +76,13 @@ export type ConfigOptionsT = {
   resetCache?: boolean,
   watchFolders?: string[],
   sourceExts?: string[],
-  reporter?: any,
+  reporter?: any, // eslint-disable-line flowtype/no-weak-types
   config?: string,
 };
 
 /**
- * Overwrites Metro configuration with options. 
- * 
+ * Overwrites Metro configuration with options.
+ *
  * This ensures that options are always taking precedence over other
  * configuration present.
  */
@@ -100,24 +102,21 @@ const overwriteWithOptions = (config: ConfigT, options: ConfigOptionsT) => {
   if (options.resetCache) {
     config.resetCache = options.resetCache;
   }
-  
+
   if (options.watchFolders) {
     config.watchFolders = options.watchFolders;
   }
 
-  if (
-    options.sourceExts
-    && options.sourceExts !== config.resolver.sourceExts
-  ) {
+  if (options.sourceExts && options.sourceExts !== config.resolver.sourceExts) {
     config.resolver.sourceExts = options.sourceExts.concat(
-      config.resolver.sourceExts,
+      config.resolver.sourceExts
     );
   }
 };
 
 /**
  * Loads Metro Config and applies `options` on top of the resolved config.
- * 
+ *
  * This allows the CLI to always overwrite the file settings.
  */
 module.exports = async function load(
@@ -125,11 +124,14 @@ module.exports = async function load(
   options?: ConfigOptionsT = {}
 ): Promise<ConfigT> {
   const defaultConfig = getDefaultConfig(projectRoot);
-  
-  const config = await loadConfig({
-    cwd: projectRoot,
-    config: options.config
-  }, defaultConfig);
+
+  const config = await loadConfig(
+    {
+      cwd: projectRoot,
+      config: options.config,
+    },
+    defaultConfig
+  );
 
   if (options) {
     overwriteWithOptions(config, options);
diff --git a/packages/local-cli/util/parseCommandLine.js b/packages/local-cli/util/parseCommandLine.js
deleted file mode 100644
index e0d58308a..000000000
--- a/packages/local-cli/util/parseCommandLine.js
+++ /dev/null
@@ -1,81 +0,0 @@
-/**
- * Copyright (c) Facebook, Inc. and its affiliates.
- *
- * This source code is licensed under the MIT license found in the
- * LICENSE file in the root directory of this source tree.
- *
- * Wrapper on-top of `optimist` in order to properly support boolean flags
- * and have a slightly less awkward API.
- *
- * Usage example:
- *   var argv = parseCommandLine([{
- *     command: 'web',
- *     description: 'Run in a web browser instead of iOS',
- *     default: true
- *   }])
- *
- * NOTE: This file is used internally at Facebook and not in `local-cli` itself.
- * No changes should be made to this file without prior discussion with FB team.
- *
- * @format
- */
-
-'use strict';
-
-var optimistModule = require('optimist');
-
-function parseCommandLine(config, args) {
-  var optimist = new optimistModule();
-  args = args || process.argv;
-  // optimist default API requires you to write the command name three time
-  // This is a small wrapper to accept an object instead
-  for (var i = 0; i < config.length; ++i) {
-    if (config[i].type === 'string') {
-      optimist.string(config[i].command);
-    } else {
-      optimist.boolean(config[i].command);
-    }
-
-    optimist
-      .default(config[i].command, config[i].default)
-      .describe(config[i].command, config[i].description);
-
-    if (config[i].required) {
-      optimist.demand(config[i].command);
-    }
-  }
-  var argv = optimist.parse(args);
-
-  // optimist doesn't have support for --dev=false, instead it returns 'false'
-  for (var i = 0; i < config.length; ++i) {
-    var command = config[i].command;
-    if (argv[command] === undefined) {
-      argv[command] = config[i].default;
-    }
-    if (argv[command] === 'true') {
-      argv[command] = true;
-    }
-    if (argv[command] === 'false') {
-      argv[command] = false;
-    }
-    if (config[i].type === 'string') {
-      // According to https://github.com/substack/node-optimist#numbers,
-      // every argument that looks like a number should be converted to one.
-      var strValue = argv[command];
-      var numValue = strValue ? Number(strValue) : undefined;
-      if (typeof numValue === 'number' && !isNaN(numValue)) {
-        argv[command] = numValue;
-      }
-    }
-  }
-
-  // Show --help
-  if (argv.help || argv.h) {
-    optimist.showHelp();
-    process.exit();
-  }
-
-  return argv;
-}
-
-module.exports = parseCommandLine;
diff --git a/packages/local-cli/util/walk.js b/packages/local-cli/util/walk.js
index b7658dbb8..743c87e84 100644
--- a/packages/local-cli/util/walk.js
+++ b/packages/local-cli/util/walk.js
@@ -7,8 +7,6 @@
  * @format
  */
 
-'use strict';
-
 const fs = require('fs');
 const path = require('path');
 
@@ -17,10 +15,9 @@ function walk(current) {
     return [current];
   }
 
-  const files = fs.readdirSync(current).map(child => {
-    child = path.join(current, child);
-    return walk(child);
-  });
+  const files = fs
+    .readdirSync(current)
+    .map(child => walk(path.join(current, child)));
   return [].concat.apply([current], files);
 }
 
diff --git a/packages/local-cli/util/yarn.js b/packages/local-cli/util/yarn.js
index b5f73bee6..37ce21bbe 100644
--- a/packages/local-cli/util/yarn.js
+++ b/packages/local-cli/util/yarn.js
@@ -7,9 +7,7 @@
  * @format
  */
 
-'use strict';
-
-const execSync = require('child_process').execSync;
+const { execSync } = require('child_process');
 const fs = require('fs');
 const path = require('path');
 const semver = require('semver');
@@ -34,11 +32,10 @@ function getYarnVersionIfAvailable() {
   try {
     if (semver.gte(yarnVersion, '0.16.0')) {
       return yarnVersion;
-    } else {
-      return null;
     }
+    return null;
   } catch (error) {
-    console.error('Cannot parse yarn version: ' + yarnVersion);
+    console.error(`Cannot parse yarn version: ${yarnVersion}`);
     return null;
   }
 }
@@ -55,6 +52,6 @@ function isGlobalCliUsingYarn(projectDir) {
 }
 
 module.exports = {
-  getYarnVersionIfAvailable: getYarnVersionIfAvailable,
-  isGlobalCliUsingYarn: isGlobalCliUsingYarn,
+  getYarnVersionIfAvailable,
+  isGlobalCliUsingYarn,
 };
diff --git a/yarn.lock b/yarn.lock
index 9fb21203d..b9a20282e 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -627,6 +627,13 @@
     "@babel/helper-plugin-utils" "^7.0.0"
     "@babel/helper-regex" "^7.0.0"
 
+"@babel/plugin-transform-strict-mode@^7.2.0":
+  version "7.2.0"
+  resolved "https://registry.yarnpkg.com/@babel/plugin-transform-strict-mode/-/plugin-transform-strict-mode-7.2.0.tgz#1aff4b99ce987b47152566a987e9469e47b96626"
+  integrity sha512-BJ5BF9+9zWTVCLe+nfLSfHUC0V/ly+ipMxVUdFjwlHFJ+Ue8WudbNh0ddzN0NnAQX5Kg0uk+DgRoGOJdnfNJgg==
+  dependencies:
+    "@babel/helper-plugin-utils" "^7.0.0"
+
 "@babel/plugin-transform-template-literals@^7.0.0":
   version "7.0.0"
   resolved "https://registry.yarnpkg.com/@babel/plugin-transform-template-literals/-/plugin-transform-template-literals-7.0.0.tgz#084f1952efe5b153ddae69eb8945f882c7a97c65"
@@ -779,6 +786,22 @@
     lodash "^4.17.10"
     to-fast-properties "^2.0.0"
 
+"@callstack/eslint-config@^3.0.2":
+  version "3.0.2"
+  resolved "https://registry.yarnpkg.com/@callstack/eslint-config/-/eslint-config-3.0.2.tgz#e40fcf73749aa8fb0b83bf243a2d6fdbc416fbd2"
+  integrity sha512-Frzn1E/egdqppp/2OLi76SMa6Z3yv4oRDjXDdYPCPtEJDyjzUh2lfTpURqziKbACUexTXMxAA+XMN0BSJ9RgUw==
+  dependencies:
+    babel-eslint "^10.0.1"
+    eslint-config-airbnb "^17.1.0"
+    eslint-config-prettier "^3.0.1"
+    eslint-plugin-flowtype "^3.0.0"
+    eslint-plugin-import "^2.14.0"
+    eslint-plugin-jest "^21.21.0"
+    eslint-plugin-jsx-a11y "^6.1.1"
+    eslint-plugin-prettier "^3.0.0"
+    eslint-plugin-react "^7.5.1"
+    prettier "^1.14.2"
+
 abab@^2.0.0:
   version "2.0.0"
   resolved "https://registry.yarnpkg.com/abab/-/abab-2.0.0.tgz#aba0ab4c5eee2d4c79d3487d85450fb2376ebb0f"
@@ -927,6 +950,14 @@ argparse@^1.0.7:
   dependencies:
     sprintf-js "~1.0.2"
 
+aria-query@^3.0.0:
+  version "3.0.0"
+  resolved "https://registry.yarnpkg.com/aria-query/-/aria-query-3.0.0.tgz#65b3fcc1ca1155a8c9ae64d6eee297f15d5133cc"
+  integrity sha1-ZbP8wcoRVajJrmTW7uKX8V1RM8w=
+  dependencies:
+    ast-types-flow "0.0.7"
+    commander "^2.11.0"
+
 arr-diff@^1.0.1:
   version "1.1.0"
   resolved "https://registry.yarnpkg.com/arr-diff/-/arr-diff-1.1.0.tgz#687c32758163588fef7de7b36fabe495eb1a399a"
@@ -964,6 +995,14 @@ array-filter@~0.0.0:
   version "0.0.1"
   resolved "https://registry.yarnpkg.com/array-filter/-/array-filter-0.0.1.tgz#7da8cf2e26628ed732803581fd21f67cacd2eeec"
 
+array-includes@^3.0.3:
+  version "3.0.3"
+  resolved "https://registry.yarnpkg.com/array-includes/-/array-includes-3.0.3.tgz#184b48f62d92d7452bb31b323165c7f8bd02266d"
+  integrity sha1-GEtI9i2S10UrsxsyMWXH+L0CJm0=
+  dependencies:
+    define-properties "^1.1.2"
+    es-abstract "^1.7.0"
+
 array-map@~0.0.0:
   version "0.0.0"
   resolved "https://registry.yarnpkg.com/array-map/-/array-map-0.0.0.tgz#88a2bab73d1cf7bcd5c1b118a003f66f665fa662"
@@ -1021,6 +1060,11 @@ assign-symbols@^1.0.0:
   version "1.0.0"
   resolved "https://registry.yarnpkg.com/assign-symbols/-/assign-symbols-1.0.0.tgz#59667f41fadd4f20ccbc2bb96b8d4f7f78ec0367"
 
+ast-types-flow@0.0.7, ast-types-flow@^0.0.7:
+  version "0.0.7"
+  resolved "https://registry.yarnpkg.com/ast-types-flow/-/ast-types-flow-0.0.7.tgz#f70b735c6bca1a5c9c22d982c3e39e7feba3bdad"
+  integrity sha1-9wtzXGvKGlycItmCw+Oef+ujva0=
+
 astral-regex@^1.0.0:
   version "1.0.0"
   resolved "https://registry.yarnpkg.com/astral-regex/-/astral-regex-1.0.0.tgz#6c8c3fb827dd43ee3918f27b82782ab7658a6fd9"
@@ -1055,6 +1099,13 @@ aws4@^1.8.0:
   version "1.8.0"
   resolved "https://registry.yarnpkg.com/aws4/-/aws4-1.8.0.tgz#f0e003d9ca9e7f59c7a508945d7b2ef9a04a542f"
 
+axobject-query@^2.0.1:
+  version "2.0.2"
+  resolved "https://registry.yarnpkg.com/axobject-query/-/axobject-query-2.0.2.tgz#ea187abe5b9002b377f925d8bf7d1c561adf38f9"
+  integrity sha512-MCeek8ZH7hKyO1rWUbKNQBbl4l2eY0ntk7OGi+q0RlafrCnfPxC06WZA+uebCfmYp4mNU9jRBP1AhGyf8+W3ww==
+  dependencies:
+    ast-types-flow "0.0.7"
+
 babel-code-frame@^6.26.0:
   version "6.26.0"
   resolved "https://registry.yarnpkg.com/babel-code-frame/-/babel-code-frame-6.26.0.tgz#63fd43f7dc1e3bb7ce35947db8fe369a3f58c74b"
@@ -1091,6 +1142,18 @@ babel-core@^6.0.0, babel-core@^6.26.0:
     slash "^1.0.0"
     source-map "^0.5.7"
 
+babel-eslint@^10.0.1:
+  version "10.0.1"
+  resolved "https://registry.yarnpkg.com/babel-eslint/-/babel-eslint-10.0.1.tgz#919681dc099614cd7d31d45c8908695092a1faed"
+  integrity sha512-z7OT1iNV+TjOwHNLLyJk+HN+YVWX+CLE6fPD2SymJZOZQBs+QIexFjhm4keGTm8MW9xr4EC9Q0PbaLB24V5GoQ==
+  dependencies:
+    "@babel/code-frame" "^7.0.0"
+    "@babel/parser" "^7.0.0"
+    "@babel/traverse" "^7.0.0"
+    "@babel/types" "^7.0.0"
+    eslint-scope "3.7.1"
+    eslint-visitor-keys "^1.0.0"
+
 babel-generator@^6.18.0, babel-generator@^6.26.0:
   version "6.26.1"
   resolved "https://registry.yarnpkg.com/babel-generator/-/babel-generator-6.26.1.tgz#1844408d3b8f0d35a404ea7ac180f087a601bd90"
@@ -1523,7 +1586,7 @@ combined-stream@^1.0.6, combined-stream@~1.0.6:
   dependencies:
     delayed-stream "~1.0.0"
 
-commander@^2.9.0:
+commander@^2.11.0, commander@^2.9.0:
   version "2.19.0"
   resolved "https://registry.yarnpkg.com/commander/-/commander-2.19.0.tgz#f6198aa84e5b83c46054b94ddedbfed5ee9ff12a"
 
@@ -1587,6 +1650,11 @@ console-control-strings@^1.0.0, console-control-strings@~1.1.0:
   version "1.1.0"
   resolved "https://registry.yarnpkg.com/console-control-strings/-/console-control-strings-1.1.0.tgz#3d7cf4464db6446ea644bf4b39507f9851008e8e"
 
+contains-path@^0.1.0:
+  version "0.1.0"
+  resolved "https://registry.yarnpkg.com/contains-path/-/contains-path-0.1.0.tgz#fe8cf184ff6670b6baef01a9d4861a5cbec4120a"
+  integrity sha1-/ozxhP9mcLa67wGp1IYaXL7EEgo=
+
 convert-source-map@^1.1.0, convert-source-map@^1.4.0, convert-source-map@^1.5.1:
   version "1.6.0"
   resolved "https://registry.yarnpkg.com/convert-source-map/-/convert-source-map-1.6.0.tgz#51b537a8c43e0f04dec1993bffcdd504e758ac20"
@@ -1659,6 +1727,11 @@ cycle@1.0.x:
   version "1.0.3"
   resolved "https://registry.yarnpkg.com/cycle/-/cycle-1.0.3.tgz#21e80b2be8580f98b468f379430662b046c34ad2"
 
+damerau-levenshtein@^1.0.4:
+  version "1.0.4"
+  resolved "https://registry.yarnpkg.com/damerau-levenshtein/-/damerau-levenshtein-1.0.4.tgz#03191c432cb6eea168bb77f3a55ffdccb8978514"
+  integrity sha1-AxkcQyy27qFou3fzpV/9zLiXhRQ=
+
 dashdash@^1.12.0:
   version "1.14.1"
   resolved "https://registry.yarnpkg.com/dashdash/-/dashdash-1.14.1.tgz#853cfa0f7cbe2fed5de20326b8dd581035f6e2f0"
@@ -1798,6 +1871,14 @@ diff@^3.2.0:
   version "3.5.0"
   resolved "https://registry.yarnpkg.com/diff/-/diff-3.5.0.tgz#800c0dd1e0a8bfbc95835c202ad220fe317e5a12"
 
+doctrine@1.5.0:
+  version "1.5.0"
+  resolved "https://registry.yarnpkg.com/doctrine/-/doctrine-1.5.0.tgz#379dce730f6166f76cefa4e6707a159b02c5a6fa"
+  integrity sha1-N53Ocw9hZvds76TmcHoVmwLFpvo=
+  dependencies:
+    esutils "^2.0.2"
+    isarray "^1.0.0"
+
 doctrine@^2.1.0:
   version "2.1.0"
   resolved "https://registry.yarnpkg.com/doctrine/-/doctrine-2.1.0.tgz#5cd01fc101621b42c4cd7f5d1a66243716d3f39d"
@@ -1829,6 +1910,11 @@ electron-to-chromium@^1.3.82:
   version "1.3.83"
   resolved "https://registry.yarnpkg.com/electron-to-chromium/-/electron-to-chromium-1.3.83.tgz#74584eb0972bb6777811c5d68d988c722f5e6666"
 
+emoji-regex@^6.5.1:
+  version "6.5.1"
+  resolved "https://registry.yarnpkg.com/emoji-regex/-/emoji-regex-6.5.1.tgz#9baea929b155565c11ea41c6626eaa65cef992c2"
+  integrity sha512-PAHp6TxrCy7MGMFidro8uikr+zlJJKJ/Q6mm2ExZ7HwkyR9lSVFfE3kt36qcwa24BQL7y0G9axycGjK1A/0uNQ==
+
 encodeurl@~1.0.1, encodeurl@~1.0.2:
   version "1.0.2"
   resolved "https://registry.yarnpkg.com/encodeurl/-/encodeurl-1.0.2.tgz#ad3ff4c86ec2d029322f5a02c3a9a606c95b3f59"
@@ -1862,7 +1948,7 @@ errorhandler@^1.5.0:
     accepts "~1.3.3"
     escape-html "~1.0.3"
 
-es-abstract@^1.5.1:
+es-abstract@^1.5.1, es-abstract@^1.6.1, es-abstract@^1.7.0:
   version "1.12.0"
   resolved "https://registry.yarnpkg.com/es-abstract/-/es-abstract-1.12.0.tgz#9dbbdd27c6856f0001421ca18782d786bf8a6165"
   dependencies:
@@ -1899,6 +1985,120 @@ escodegen@^1.9.1:
   optionalDependencies:
     source-map "~0.6.1"
 
+eslint-config-airbnb-base@^13.1.0:
+  version "13.1.0"
+  resolved "https://registry.yarnpkg.com/eslint-config-airbnb-base/-/eslint-config-airbnb-base-13.1.0.tgz#b5a1b480b80dfad16433d6c4ad84e6605052c05c"
+  integrity sha512-XWwQtf3U3zIoKO1BbHh6aUhJZQweOwSt4c2JrPDg9FP3Ltv3+YfEv7jIDB8275tVnO/qOHbfuYg3kzw6Je7uWw==
+  dependencies:
+    eslint-restricted-globals "^0.1.1"
+    object.assign "^4.1.0"
+    object.entries "^1.0.4"
+
+eslint-config-airbnb@^17.1.0:
+  version "17.1.0"
+  resolved "https://registry.yarnpkg.com/eslint-config-airbnb/-/eslint-config-airbnb-17.1.0.tgz#3964ed4bc198240315ff52030bf8636f42bc4732"
+  integrity sha512-R9jw28hFfEQnpPau01NO5K/JWMGLi6aymiF6RsnMURjTk+MqZKllCqGK/0tOvHkPi/NWSSOU2Ced/GX++YxLnw==
+  dependencies:
+    eslint-config-airbnb-base "^13.1.0"
+    object.assign "^4.1.0"
+    object.entries "^1.0.4"
+
+eslint-config-prettier@^3.0.1:
+  version "3.3.0"
+  resolved "https://registry.yarnpkg.com/eslint-config-prettier/-/eslint-config-prettier-3.3.0.tgz#41afc8d3b852e757f06274ed6c44ca16f939a57d"
+  integrity sha512-Bc3bh5bAcKNvs3HOpSi6EfGA2IIp7EzWcg2tS4vP7stnXu/J1opihHDM7jI9JCIckyIDTgZLSWn7J3HY0j2JfA==
+  dependencies:
+    get-stdin "^6.0.0"
+
+eslint-import-resolver-node@^0.3.1:
+  version "0.3.2"
+  resolved "https://registry.yarnpkg.com/eslint-import-resolver-node/-/eslint-import-resolver-node-0.3.2.tgz#58f15fb839b8d0576ca980413476aab2472db66a"
+  integrity sha512-sfmTqJfPSizWu4aymbPr4Iidp5yKm8yDkHp+Ir3YiTHiiDfxh69mOUsmiqW6RZ9zRXFaF64GtYmN7e+8GHBv6Q==
+  dependencies:
+    debug "^2.6.9"
+    resolve "^1.5.0"
+
+eslint-module-utils@^2.2.0:
+  version "2.2.0"
+  resolved "https://registry.yarnpkg.com/eslint-module-utils/-/eslint-module-utils-2.2.0.tgz#b270362cd88b1a48ad308976ce7fa54e98411746"
+  integrity sha1-snA2LNiLGkitMIl2zn+lTphBF0Y=
+  dependencies:
+    debug "^2.6.8"
+    pkg-dir "^1.0.0"
+
+eslint-plugin-flowtype@^3.0.0:
+  version "3.2.0"
+  resolved "https://registry.yarnpkg.com/eslint-plugin-flowtype/-/eslint-plugin-flowtype-3.2.0.tgz#824364ed5940a404b91326fdb5a313a2a74760df"
+  integrity sha512-baJmzngM6UKbEkJ5OY3aGw2zjXBt5L2QKZvTsOlXX7yHKIjNRrlJx2ods8Rng6EdqPR9rVNIQNYHpTs0qfn2qA==
+  dependencies:
+    lodash "^4.17.10"
+
+eslint-plugin-import@^2.14.0:
+  version "2.14.0"
+  resolved "https://registry.yarnpkg.com/eslint-plugin-import/-/eslint-plugin-import-2.14.0.tgz#6b17626d2e3e6ad52cfce8807a845d15e22111a8"
+  integrity sha512-FpuRtniD/AY6sXByma2Wr0TXvXJ4nA/2/04VPlfpmUDPOpOY264x+ILiwnrk/k4RINgDAyFZByxqPUbSQ5YE7g==
+  dependencies:
+    contains-path "^0.1.0"
+    debug "^2.6.8"
+    doctrine "1.5.0"
+    eslint-import-resolver-node "^0.3.1"
+    eslint-module-utils "^2.2.0"
+    has "^1.0.1"
+    lodash "^4.17.4"
+    minimatch "^3.0.3"
+    read-pkg-up "^2.0.0"
+    resolve "^1.6.0"
+
+eslint-plugin-jest@^21.21.0:
+  version "21.27.2"
+  resolved "https://registry.yarnpkg.com/eslint-plugin-jest/-/eslint-plugin-jest-21.27.2.tgz#2a795b7c3b5e707df48a953d651042bd01d7b0a8"
+  integrity sha512-0E4OIgBJVlAmf1KfYFtZ3gYxgUzC5Eb3Jzmrc9ikI1OY+/cM8Kh72Ti7KfpeHNeD3HJNf9SmEfmvQLIz44Hrhw==
+
+eslint-plugin-jsx-a11y@^6.1.1:
+  version "6.1.2"
+  resolved "https://registry.yarnpkg.com/eslint-plugin-jsx-a11y/-/eslint-plugin-jsx-a11y-6.1.2.tgz#69bca4890b36dcf0fe16dd2129d2d88b98f33f88"
+  integrity sha512-7gSSmwb3A+fQwtw0arguwMdOdzmKUgnUcbSNlo+GjKLAQFuC2EZxWqG9XHRI8VscBJD5a8raz3RuxQNFW+XJbw==
+  dependencies:
+    aria-query "^3.0.0"
+    array-includes "^3.0.3"
+    ast-types-flow "^0.0.7"
+    axobject-query "^2.0.1"
+    damerau-levenshtein "^1.0.4"
+    emoji-regex "^6.5.1"
+    has "^1.0.3"
+    jsx-ast-utils "^2.0.1"
+
+eslint-plugin-prettier@^3.0.0:
+  version "3.0.0"
+  resolved "https://registry.yarnpkg.com/eslint-plugin-prettier/-/eslint-plugin-prettier-3.0.0.tgz#f6b823e065f8c36529918cdb766d7a0e975ec30c"
+  integrity sha512-4g11opzhqq/8+AMmo5Vc2Gn7z9alZ4JqrbZ+D4i8KlSyxeQhZHlmIrY8U9Akf514MoEhogPa87Jgkq87aZ2Ohw==
+  dependencies:
+    prettier-linter-helpers "^1.0.0"
+
+eslint-plugin-react@^7.5.1:
+  version "7.11.1"
+  resolved "https://registry.yarnpkg.com/eslint-plugin-react/-/eslint-plugin-react-7.11.1.tgz#c01a7af6f17519457d6116aa94fc6d2ccad5443c"
+  integrity sha512-cVVyMadRyW7qsIUh3FHp3u6QHNhOgVrLQYdQEB1bPWBsgbNCHdFAeNMquBMCcZJu59eNthX053L70l7gRt4SCw==
+  dependencies:
+    array-includes "^3.0.3"
+    doctrine "^2.1.0"
+    has "^1.0.3"
+    jsx-ast-utils "^2.0.1"
+    prop-types "^15.6.2"
+
+eslint-restricted-globals@^0.1.1:
+  version "0.1.1"
+  resolved "https://registry.yarnpkg.com/eslint-restricted-globals/-/eslint-restricted-globals-0.1.1.tgz#35f0d5cbc64c2e3ed62e93b4b1a7af05ba7ed4d7"
+  integrity sha1-NfDVy8ZMLj7WLpO0saevBbp+1Nc=
+
+eslint-scope@3.7.1:
+  version "3.7.1"
+  resolved "https://registry.yarnpkg.com/eslint-scope/-/eslint-scope-3.7.1.tgz#3d63c3edfda02e06e01a452ad88caacc7cdcb6e8"
+  integrity sha1-PWPD7f2gLgbgGkUq2IyqzHzctug=
+  dependencies:
+    esrecurse "^4.1.0"
+    estraverse "^4.1.1"
+
 eslint-scope@^4.0.0:
   version "4.0.0"
   resolved "https://registry.yarnpkg.com/eslint-scope/-/eslint-scope-4.0.0.tgz#50bf3071e9338bcdc43331794a0cb533f0136172"
@@ -1914,6 +2114,49 @@ eslint-visitor-keys@^1.0.0:
   version "1.0.0"
   resolved "https://registry.yarnpkg.com/eslint-visitor-keys/-/eslint-visitor-keys-1.0.0.tgz#3f3180fb2e291017716acb4c9d6d5b5c34a6a81d"
 
+eslint@^5.10.0:
+  version "5.10.0"
+  resolved "https://registry.yarnpkg.com/eslint/-/eslint-5.10.0.tgz#24adcbe92bf5eb1fc2d2f2b1eebe0c5e0713903a"
+  integrity sha512-HpqzC+BHULKlnPwWae9MaVZ5AXJKpkxCVXQHrFaRw3hbDj26V/9ArYM4Rr/SQ8pi6qUPLXSSXC4RBJlyq2Z2OQ==
+  dependencies:
+    "@babel/code-frame" "^7.0.0"
+    ajv "^6.5.3"
+    chalk "^2.1.0"
+    cross-spawn "^6.0.5"
+    debug "^4.0.1"
+    doctrine "^2.1.0"
+    eslint-scope "^4.0.0"
+    eslint-utils "^1.3.1"
+    eslint-visitor-keys "^1.0.0"
+    espree "^5.0.0"
+    esquery "^1.0.1"
+    esutils "^2.0.2"
+    file-entry-cache "^2.0.0"
+    functional-red-black-tree "^1.0.1"
+    glob "^7.1.2"
+    globals "^11.7.0"
+    ignore "^4.0.6"
+    imurmurhash "^0.1.4"
+    inquirer "^6.1.0"
+    js-yaml "^3.12.0"
+    json-stable-stringify-without-jsonify "^1.0.1"
+    levn "^0.3.0"
+    lodash "^4.17.5"
+    minimatch "^3.0.4"
+    mkdirp "^0.5.1"
+    natural-compare "^1.4.0"
+    optionator "^0.8.2"
+    path-is-inside "^1.0.2"
+    pluralize "^7.0.0"
+    progress "^2.0.0"
+    regexpp "^2.0.1"
+    require-uncached "^1.0.3"
+    semver "^5.5.1"
+    strip-ansi "^4.0.0"
+    strip-json-comments "^2.0.1"
+    table "^5.0.2"
+    text-table "^0.2.0"
+
 eslint@^5.7.0:
   version "5.8.0"
   resolved "https://registry.yarnpkg.com/eslint/-/eslint-5.8.0.tgz#91fbf24f6e0471e8fdf681a4d9dd1b2c9f28309b"
@@ -1965,6 +2208,15 @@ espree@^4.0.0:
     acorn-jsx "^5.0.0"
     eslint-visitor-keys "^1.0.0"
 
+espree@^5.0.0:
+  version "5.0.0"
+  resolved "https://registry.yarnpkg.com/espree/-/espree-5.0.0.tgz#fc7f984b62b36a0f543b13fb9cd7b9f4a7f5b65c"
+  integrity sha512-1MpUfwsdS9MMoN7ZXqAr9e9UKdVHDcvrJpyx7mm1WuQlx/ygErEQBzgi5Nh5qBHIoYweprhtMkTCb9GhcAIcsA==
+  dependencies:
+    acorn "^6.0.2"
+    acorn-jsx "^5.0.0"
+    eslint-visitor-keys "^1.0.0"
+
 esprima@^3.1.3:
   version "3.1.3"
   resolved "https://registry.yarnpkg.com/esprima/-/esprima-3.1.3.tgz#fdca51cee6133895e3c88d535ce49dbff62a4633"
@@ -2174,6 +2426,11 @@ fast-deep-equal@^2.0.1:
   version "2.0.1"
   resolved "https://registry.yarnpkg.com/fast-deep-equal/-/fast-deep-equal-2.0.1.tgz#7b05218ddf9667bf7f370bf7fdb2cb15fdd0aa49"
 
+fast-diff@^1.1.2:
+  version "1.2.0"
+  resolved "https://registry.yarnpkg.com/fast-diff/-/fast-diff-1.2.0.tgz#73ee11982d86caaf7959828d519cfe927fac5f03"
+  integrity sha512-xJuoT5+L99XlZ8twedaRf6Ax2TgQVxvgZOYoPKqZufmJib0tL2tegPBOZb1pVNgIhlqDlA0eO0c3wBvQcmzx4w==
+
 fast-json-stable-stringify@^2.0.0:
   version "2.0.0"
   resolved "https://registry.yarnpkg.com/fast-json-stable-stringify/-/fast-json-stable-stringify-2.0.0.tgz#d5142c0caee6b1189f87d3a76111064f86c8bbf2"
@@ -2386,7 +2643,7 @@ fsevents@^1.2.3:
     nan "^2.9.2"
     node-pre-gyp "^0.10.0"
 
-function-bind@^1.1.1:
+function-bind@^1.1.0, function-bind@^1.1.1:
   version "1.1.1"
   resolved "https://registry.yarnpkg.com/function-bind/-/function-bind-1.1.1.tgz#a56899d3ea3c9bab874bb9773b7c5ede92f4895d"
 
@@ -2421,6 +2678,11 @@ get-caller-file@^1.0.1:
   version "1.0.3"
   resolved "https://registry.yarnpkg.com/get-caller-file/-/get-caller-file-1.0.3.tgz#f978fa4c90d1dfe7ff2d6beda2a515e713bdcf4a"
 
+get-stdin@^6.0.0:
+  version "6.0.0"
+  resolved "https://registry.yarnpkg.com/get-stdin/-/get-stdin-6.0.0.tgz#9e09bf712b360ab9225e812048f71fde9c89657b"
+  integrity sha512-jp4tHawyV7+fkkSKyvjuLZswblUtz+SQKzSWnBbii16BuZksJlU1wuBYXY75r+duh/llF1ur6oNwi+2ZzjKZ7g==
+
 get-stream@^3.0.0:
   version "3.0.0"
   resolved "http://registry.npmjs.org/get-stream/-/get-stream-3.0.0.tgz#8e943d1358dc37555054ecbe2edb05aa174ede14"
@@ -2569,7 +2831,7 @@ has-values@^1.0.0:
     is-number "^3.0.0"
     kind-of "^4.0.0"
 
-has@^1.0.1:
+has@^1.0.1, has@^1.0.3:
   version "1.0.3"
   resolved "https://registry.yarnpkg.com/has/-/has-1.0.3.tgz#722d7cbfc1f6aa8241f16dd814e011e1f41e8796"
   dependencies:
@@ -2918,7 +3180,7 @@ is-windows@^1.0.2:
   version "1.0.2"
   resolved "https://registry.yarnpkg.com/is-windows/-/is-windows-1.0.2.tgz#d1850eb9791ecd18e6182ce12a30f396634bb19d"
 
-isarray@1.0.0, isarray@~1.0.0:
+isarray@1.0.0, isarray@^1.0.0, isarray@~1.0.0:
   version "1.0.0"
   resolved "https://registry.yarnpkg.com/isarray/-/isarray-1.0.0.tgz#bb935d48582cba168c06834957a54a3e07124f11"
 
@@ -3474,6 +3736,13 @@ jsprim@^1.2.2:
     json-schema "0.2.3"
     verror "1.10.0"
 
+jsx-ast-utils@^2.0.1:
+  version "2.0.1"
+  resolved "https://registry.yarnpkg.com/jsx-ast-utils/-/jsx-ast-utils-2.0.1.tgz#e801b1b39985e20fffc87b40e3748080e2dcac7f"
+  integrity sha1-6AGxs5mF4g//yHtA43SAgOLcrH8=
+  dependencies:
+    array-includes "^3.0.3"
+
 kind-of@^1.1.0:
   version "1.1.0"
   resolved "http://registry.npmjs.org/kind-of/-/kind-of-1.1.0.tgz#140a3d2d41a36d2efcfa9377b62c24f8495a5c44"
@@ -4316,7 +4585,7 @@ object-copy@^0.1.0:
     define-property "^0.2.5"
     kind-of "^3.0.3"
 
-object-keys@^1.0.12:
+object-keys@^1.0.11, object-keys@^1.0.12:
   version "1.0.12"
   resolved "https://registry.yarnpkg.com/object-keys/-/object-keys-1.0.12.tgz#09c53855377575310cca62f55bb334abff7b3ed2"
 
@@ -4326,6 +4595,26 @@ object-visit@^1.0.0:
   dependencies:
     isobject "^3.0.0"
 
+object.assign@^4.1.0:
+  version "4.1.0"
+  resolved "https://registry.yarnpkg.com/object.assign/-/object.assign-4.1.0.tgz#968bf1100d7956bb3ca086f006f846b3bc4008da"
+  integrity sha512-exHJeq6kBKj58mqGyTQ9DFvrZC/eR6OwxzoM9YRoGBqrXYonaFyGiFMuc9VZrXf7DarreEwMpurG3dd+CNyW5w==
+  dependencies:
+    define-properties "^1.1.2"
+    function-bind "^1.1.1"
+    has-symbols "^1.0.0"
+    object-keys "^1.0.11"
+
+object.entries@^1.0.4:
+  version "1.0.4"
+  resolved "https://registry.yarnpkg.com/object.entries/-/object.entries-1.0.4.tgz#1bf9a4dd2288f5b33f3a993d257661f05d161a5f"
+  integrity sha1-G/mk3SKI9bM/Opk9JXZh8F0WGl8=
+  dependencies:
+    define-properties "^1.1.2"
+    es-abstract "^1.6.1"
+    function-bind "^1.1.0"
+    has "^1.0.1"
+
 object.getownpropertydescriptors@^2.0.3:
   version "2.0.3"
   resolved "https://registry.yarnpkg.com/object.getownpropertydescriptors/-/object.getownpropertydescriptors-2.0.3.tgz#8758c846f5b407adab0f236e0986f14b051caa16"
@@ -4527,7 +4816,7 @@ path-key@^2.0.0, path-key@^2.0.1:
   version "2.0.1"
   resolved "https://registry.yarnpkg.com/path-key/-/path-key-2.0.1.tgz#411cadb574c5a140d3a4b1910d40d80cc9f40b40"
 
-path-parse@^1.0.5:
+path-parse@^1.0.5, path-parse@^1.0.6:
   version "1.0.6"
   resolved "https://registry.yarnpkg.com/path-parse/-/path-parse-1.0.6.tgz#d62dbb5679405d72c4737ec58600e9ddcf06d24c"
 
@@ -4577,6 +4866,13 @@ pirates@^4.0.0:
   dependencies:
     node-modules-regexp "^1.0.0"
 
+pkg-dir@^1.0.0:
+  version "1.0.0"
+  resolved "https://registry.yarnpkg.com/pkg-dir/-/pkg-dir-1.0.0.tgz#7a4b508a8d5bb2d629d447056ff4e9c9314cf3d4"
+  integrity sha1-ektQio1bstYp1EcFb/TpyTFM89Q=
+  dependencies:
+    find-up "^1.0.0"
+
 pkg-dir@^2.0.0:
   version "2.0.0"
   resolved "https://registry.yarnpkg.com/pkg-dir/-/pkg-dir-2.0.0.tgz#f6d5d1109e19d63edf428e0bd57e12777615334b"
@@ -4643,6 +4939,18 @@ preserve@^0.2.0:
   version "0.2.0"
   resolved "https://registry.yarnpkg.com/preserve/-/preserve-0.2.0.tgz#815ed1f6ebc65926f865b310c0713bcb3315ce4b"
 
+prettier-linter-helpers@^1.0.0:
+  version "1.0.0"
+  resolved "https://registry.yarnpkg.com/prettier-linter-helpers/-/prettier-linter-helpers-1.0.0.tgz#d23d41fe1375646de2d0104d3454a3008802cf7b"
+  integrity sha512-GbK2cP9nraSSUF9N2XwUwqfzlAFlMNYYl+ShE/V+H8a9uNl/oUqB1w2EL54Jh0OlyRSd8RfWYJ3coVS4TROP2w==
+  dependencies:
+    fast-diff "^1.1.2"
+
+prettier@^1.14.2:
+  version "1.15.3"
+  resolved "https://registry.yarnpkg.com/prettier/-/prettier-1.15.3.tgz#1feaac5bdd181237b54dbe65d874e02a1472786a"
+  integrity sha512-gAU9AGAPMaKb3NNSUUuhhFAS7SCO4ALTN4nRIn6PJ075Qd28Yn2Ig2ahEJWdJwJmlEBTUfC7mMUSFy8MwsOCfg==
+
 pretty-format@24.0.0-alpha.6, pretty-format@^24.0.0-alpha.6:
   version "24.0.0-alpha.6"
   resolved "https://registry.yarnpkg.com/pretty-format/-/pretty-format-24.0.0-alpha.6.tgz#25ad2fa46b342d6278bf241c5d2114d4376fbac1"
@@ -4703,7 +5011,7 @@ prompts@^1.1.0:
     kleur "^2.0.1"
     sisteransi "^1.0.0"
 
-prop-types@^15.5.8:
+prop-types@^15.5.8, prop-types@^15.6.2:
   version "15.6.2"
   resolved "https://registry.yarnpkg.com/prop-types/-/prop-types-15.6.2.tgz#05d5ca77b4453e985d60fc7ff8c859094a497102"
   integrity sha512-3pboPvLiWD7dkI3qf3KbUe6hKFKa52w+AE0VCqECtf+QHAKgOL37tTaNCnuX1nAAQ4ZhyP+kYVKf8rLmJ/feDQ==
@@ -5070,6 +5378,13 @@ resolve@^1.3.2, resolve@^1.5.0, resolve@^1.8.1:
   dependencies:
     path-parse "^1.0.5"
 
+resolve@^1.6.0:
+  version "1.9.0"
+  resolved "https://registry.yarnpkg.com/resolve/-/resolve-1.9.0.tgz#a14c6fdfa8f92a7df1d996cb7105fa744658ea06"
+  integrity sha512-TZNye00tI67lwYvzxCxHGjwTNlUV70io54/Ed4j6PscB8xVfuBJpRenI/o6dVk0cY0PYTY27AgCoGGxRnYuItQ==
+  dependencies:
+    path-parse "^1.0.6"
+
 restore-cursor@^2.0.0:
   version "2.0.0"
   resolved "https://registry.yarnpkg.com/restore-cursor/-/restore-cursor-2.0.0.tgz#9f7ee287f82fd326d4fd162923d62129eee0dfaf"