tsconfig.json

{
  "compilerOptions": {
    "target": "es2015",                       /* Specify ECMAScript target version: 'ES3' (default), 'ES5', 'ES2015', 'ES2016', 'ES2017', 'ES2018', 'ES2019' or 'ESNEXT'. */
    "module": "commonjs",                     /* Specify module code generation: 'none', 'commonjs', 'amd', 'system', 'umd', 'es2015', or 'ESNext'. */
    "declaration": true,                      /* Generates corresponding '.d.ts' file. */
    "outDir": "bin",                         /* Redirect output structure to the directory. */
    "rootDir": "src",
    "downlevelIteration": true,               /* Provide full support for iterables in 'for-of', spread, and destructuring when targeting 'ES5' or 'ES3'. */
    "strict": true,
    "noUnusedLocals": true,                   /* Report errors on unused locals. */
    "noUnusedParameters": true,               /* Report errors on unused parameters. */
    "noImplicitReturns": true,                /* Report error when not all code paths in function return a value. */
    "esModuleInterop": true        /* Enables experimental support for emitting type metadata for decorators. */
  },
  "include": [
    "src/**/*"
  ],
  "exclude": [
    "node_modules",
    "test/**/*"
  ]
}