tsconfig.json

{
  "compilerOptions": {
    "target": "es5",
    "lib": [
      "esnext"
    ],
    "types": [
      "node"
    ],
    "module": "commonjs",
    "declaration": true,
    "experimentalDecorators": true,
    "emitDecoratorMetadata": true,
    "allowJs": false,
    "outDir": "lib",
    "inlineSourceMap": true
  },
  "include": [
    "src/**/*.ts"
  ]
}