tsconfig.json

{
  "compileOnSave": true,
  "compilerOptions": {
    "target": "es6",
    "module": "commonjs",

    "declaration": true /* Generate .d.ts files from TypeScript and JavaScript files in your project. */ /* Specify a file that bundles all outputs into one JavaScript file. If 'declaration' is true, also designates a file that bundles all .d.ts output. */,
    "outDir": "dist" /* 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. */,
    "forceConsistentCasingInFileNames": true /* Ensure that casing is correct in imports. */,

    "strict": true /* Enable all strict type-checking options. */,
    "skipLibCheck": true /* Skip type checking all .d.ts files. */,

    "inlineSourceMap": true,
    "inlineSources": true,
    "noFallthroughCasesInSwitch": true,
    "noImplicitAny": true,
    "noImplicitReturns": true,
    "noUnusedLocals": false,

    "preserveConstEnums": true,
    "lib": ["es6", "dom"],
    "alwaysStrict": true,
    "strictNullChecks": true,
    "resolveJsonModule": true,
    "typeRoots": ["node_modules/@types", "dist/index.d.ts"]
  },
  "exclude": ["tests/*.ts", "dist", "build-utils"]
}