tsconfig.json

{
  "compilerOptions": {
    /* Language and Environment */
    "target": "es2016" /* Set the JavaScript language version for emitted JavaScript and include compatible library declarations. */,
    "lib": [
      "es6"
    ] /* Specify a set of bundled library declaration files that describe the target runtime environment. */,

    /* Modules */
    "module": "commonjs" /* Specify what module code is generated. */,
    "rootDir": "src" /* Specify the root folder within your source files. */,
    "resolveJsonModule": true /* Enable importing .json files. */,

    /* JavaScript Support */
    "allowJs": true /* Allow JavaScript files to be a part of your program. Use the 'checkJS' option to get errors from these files. */,
    "outDir": "build" /* Specify an output folder for all emitted files. */,
    "esModuleInterop": true /* Emit additional JavaScript to ease support for importing CommonJS modules. This enables 'allowSyntheticDefaultImports' for type compatibility. */,
    // "preserveSymlinks": true,                         /* Disable resolving symlinks to their realpath. This correlates to the same flag in node. */
    "forceConsistentCasingInFileNames": true /* Ensure that casing is correct in imports. */,

    /* Type Checking */
    "strict": true /* Enable all strict type-checking options. */,
    "noImplicitAny": true /* Enable error reporting for expressions and declarations with an implied 'any' type. */,
    "skipLibCheck": true /* Skip type checking all .d.ts files. */
  }
}