diff --git a/.travis.yml b/.travis.yml
index e1e7f5e2..1797b138 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -2,7 +2,7 @@ language: node_js
 os:
   - linux
 node_js:
-  - "4"
   - "6"
+  - "8"
   - "node"
 after_script: npm run coverage
diff --git a/package.json b/package.json
index 933ca217..e574e428 100644
--- a/package.json
+++ b/package.json
@@ -26,19 +26,22 @@
   "author": "Ben Coe <ben@npmjs.com>",
   "license": "ISC",
   "devDependencies": {
-    "chai": "^3.5.0",
-    "coveralls": "^2.11.12",
-    "mocha": "^3.0.1",
-    "nyc": "^11.4.1",
-    "standard": "^10.0.2",
-    "standard-version": "^4.3.0"
+    "chai": "^4.2.0",
+    "coveralls": "^3.0.2",
+    "mocha": "^5.2.0",
+    "nyc": "^13.0.1",
+    "standard": "^12.0.1",
+    "standard-version": "^4.4.0"
   },
   "dependencies": {
-    "camelcase": "^4.1.0",
-    "decamelize": "^2.0.0"
+    "camelcase": "^5.0.0",
+    "decamelize": "^1.2.0"
   },
   "files": [
     "lib",
     "index.js"
-  ]
+  ],
+  "engine": {
+    "node": ">=6"
+  }
 }
diff --git a/test/yargs-parser.js b/test/yargs-parser.js
index e483536e..7f220a17 100644
--- a/test/yargs-parser.js
+++ b/test/yargs-parser.js
@@ -146,7 +146,7 @@ describe('yargs-parser', function () {
       '--other', '-99', '-220'
     ], {
       array: 'bounds',
-      narg: {'other': 2}
+      narg: { 'other': 2 }
     })
 
     argv._.should.deep.equal([-33, -177, 33])
@@ -1419,12 +1419,12 @@ describe('yargs-parser', function () {
 
   describe('array', function () {
     it('should group values into an array if the same option is specified multiple times (duplicate-arguments-array=true)', function () {
-      var parse = parser(['-v', 'a', '-v', 'b', '-v', 'c'], {configuration: {'duplicate-arguments-array': true}})
+      var parse = parser(['-v', 'a', '-v', 'b', '-v', 'c'], { configuration: { 'duplicate-arguments-array': true } })
       parse.should.have.property('v').and.deep.equal(['a', 'b', 'c'])
       parse.should.have.property('_').with.length(0)
     })
     it('should keep only the last value if the same option is specified multiple times (duplicate-arguments-false)', function () {
-      var parse = parser(['-v', 'a', '-v', 'b', '-v', 'c'], {configuration: {'duplicate-arguments-array': false}})
+      var parse = parser(['-v', 'a', '-v', 'b', '-v', 'c'], { configuration: { 'duplicate-arguments-array': false } })
       parse.should.have.property('v').and.equal('c')
       parse.should.have.property('_').with.length(0)
     })
@@ -1503,8 +1503,8 @@ describe('yargs-parser', function () {
       var result = parser(['-a=hello', 'world', '-b',
         '33', '22', '--foo', 'red', 'green',
         '--bar=cat', 'dog'], {
-          array: ['a', 'b', 'foo', 'bar']
-        })
+        array: ['a', 'b', 'foo', 'bar']
+      })
 
       Array.isArray(result.a).should.equal(true)
       result.a.should.include('hello')
@@ -2166,7 +2166,7 @@ describe('yargs-parser', function () {
           }
         })
 
-        parsed['x'].should.deep.equal({foo: ['a', 'b']})
+        parsed['x'].should.deep.equal({ foo: ['a', 'b'] })
       })
     })
 
@@ -2400,13 +2400,13 @@ describe('yargs-parser', function () {
           number: ['d'],
           count: ['e'],
           normalize: ['f'],
-          narg: {g: 2},
+          narg: { g: 2 },
           coerce: {
             h: function (arg) {
               return arg
             }
           },
-          configuration: {'set-placeholder-key': true}
+          configuration: { 'set-placeholder-key': true }
         })
         parsed.should.have.property('a')
         expect(parsed.a).to.be.equal(undefined)
@@ -2427,8 +2427,8 @@ describe('yargs-parser', function () {
       it('should not set placeholder for key with a default value', function () {
         var parsed = parser([], {
           string: ['a'],
-          default: {a: 'hello'},
-          configuration: {'set-placeholder-key': true}
+          default: { a: 'hello' },
+          configuration: { 'set-placeholder-key': true }
         })
         parsed.a.should.equal('hello')
       })
@@ -2639,7 +2639,7 @@ describe('yargs-parser', function () {
     var argv = parser([ '--foo', 'bar' ], {
       array: ['a'],
       normalize: ['a'],
-      configObjects: [{'a': ['bin/../a.txt', 'bin/../b.txt']}]
+      configObjects: [{ 'a': ['bin/../a.txt', 'bin/../b.txt'] }]
     })
     argv.a.should.deep.equal(['a.txt', 'b.txt'])
   })