tsconfig.json

{
  "compilerOptions": {
    /* Basic Options */
    "target": "ES2015",                          /* Specify ECMAScript target version: 'ES3' (default), 'ES5', 'ES2015', 'ES2016', 'ES2017', or 'ESNEXT'. */
    "module": "commonjs",                     /* Specify module code generation: 'none', 'commonjs', 'amd', 'system', 'umd', 'es2015', or 'ESNext'. */
    "lib": [
			"es6"
    ],
    "sourceMap": true,                     /* Generates corresponding '.map' file. */
    "outDir": "lib",                        /* Redirect output structure to the directory. */
    /* Strict Type-Checking Options */
    "strict": true,                            /* Enable all strict type-checking options. */
    "declaration": true,
    /* Source Map Options */
    "sourceRoot": "src"                    /* Specify the location where debugger should locate TypeScript files instead of source locations. */
  },
  "exclude": [
    "node_modules",
    "test",
    "lib"
	]
}