tsconfig.json

{
  "compilerOptions": {
    "module": "commonjs",
    "moduleResolution": "node",
    "sourceMap": true,
    "declaration": true,
    "skipLibCheck": true,
    "esModuleInterop": true,
    "noImplicitAny": true,
    "noEmitOnError": true,
    "noUnusedLocals": true,
    "strictNullChecks": true,
    "resolveJsonModule": true,
    "experimentalDecorators": true,
    "outDir": "lib",
    "target": "es5",
    "lib": ["dom", "es2015"]
  },
  "include": ["src/**/*.ts"]
}