tsconfig.json

{
  "compilerOptions": {
    /* Basic Options */
    "outDir": "build/",
    "target": "es6",                          /* Specify ECMAScript target version: 'ES3' (default), 'ES5', 'ES2015', 'ES2016', 'ES2017','ES2018' or 'ESNEXT'. */
    "module": "commonjs",                     /* Specify module code generation: 'none', 'commonjs', 'amd', 'system', 'umd', 'es2015', or 'ESNext'. */

    /* Strict Type-Checking Options */
    "strict": false,

    /* Module Resolution Options */
    "esModuleInterop": true,                   /* Enables emit interoperability between CommonJS and ES Modules via creation of namespace objects for all imports. Implies 'allowSyntheticDefaultImports'. */
    /* Additional Checks */
    "noUnusedLocals": false,                /* Report errors on unused locals. */
    "noUnusedParameters": false,            /* Report errors on unused parameters. */
  }
}