tsconfig.json

{
  "compilerOptions": {
    "target": "ESNEXT" /* Specify ECMAScript target version: 'ES3' (default), 'ES5', 'ES2015', 'ES2016', 'ES2017', 'ES2018', 'ES2019', 'ES2020', or 'ESNEXT'. */,
    "module": "commonjs" /* Specify module code generation: 'none', 'commonjs', 'amd', 'system', 'umd', 'es2015', 'es2020', or 'ESNext'. */,
    "lib": ["ESNext"] /* Specify library files to be included in the compilation. */,
    "declaration": true /* Generates corresponding '.d.ts' file. */,
    "outDir": "dist" /* Redirect output structure to the directory. */,
    "strict": true /* Enable all strict type-checking options. */,
    "noImplicitAny": true /* Raise error on expressions and declarations with an implied 'any' type. */,
    "pretty": true,
    "strictNullChecks": true /* Enable strict null checks. */,
    "strictPropertyInitialization": true /* Enable strict checking of property initialization in classes. */,
    "noImplicitThis": true /* Raise error on 'this' expressions with an implied 'any' type. */,
    "alwaysStrict": true /* Parse in strict mode and emit "use strict" for each source file. */,
    "noUnusedLocals": true /* Report errors on unused locals. */,
    "noUnusedParameters": true /* Report errors on unused parameters. */,
    "moduleResolution": "node" /* Specify module resolution strategy: 'node' (Node.js) or 'classic' (TypeScript pre-1.6). */,
    "esModuleInterop": true /* Enables emit interoperability between CommonJS and ES Modules via creation of namespace objects for all imports. Implies 'allowSyntheticDefaultImports'. */,
    "skipLibCheck": true /* Skip type checking of declaration files. */,
    "forceConsistentCasingInFileNames": true /* Disallow inconsistently-cased references to the same file. */
  },
  "include": ["src", "spec"],
  "exclude": ["node_modules"]
}