tsconfig.json

{
  "compilerOptions": {
    "declaration": true,
    "removeComments": true,
    "emitDecoratorMetadata": true,
    "experimentalDecorators": true,
    "sourceMap": true,
    "target": "es2017",
    "outDir": "build/main",
    "rootDir": "src",
    "incremental": true,
    "moduleResolution": "node",

    "module": "commonjs",
    "esModuleInterop": true /* Enables emit interoperability between CommonJS and ES Modules via creation of namespace objects for all imports. Implies 'allowSyntheticDefaultImports'. */,

    /* Experimental Options */
    // "experimentalDecorators": true /* Enables experimental support for ES7 decorators. */,
    // "emitDecoratorMetadata": true /* Enables experimental support for emitting type metadata for decorators. */,

    "lib": ["es2017"],
    "types": ["node"],
    "typeRoots": ["node_modules/@types", "src/types"]
  },
  "exclude": ["node_modules", "test", "dist", "**/*spec.ts"],
  "compileOnSave": false
}