tsconfig.json

{
  "compilerOptions": {
    "module": "esnext",
    "lib": ["es2017", "dom", "dom.iterable"],
    "declaration": true,
    "emitDeclarationOnly": true,
    "outDir": "./types",
    "rootDir": "./src",
    "strict": true,
    "noUnusedLocals": true,
    "noUnusedParameters": true,
    "noImplicitReturns": true,
    "noFallthroughCasesInSwitch": true,
    "moduleResolution": "node",
    "allowSyntheticDefaultImports": true,
    "experimentalDecorators": true,
    "forceConsistentCasingInFileNames": true,
    "useDefineForClassFields": false,
    // // The next 2 below are a workaround for: https://github.com/typestack/class-transformer/issues/472
    // // https://github.com/apollographql/graphql-tag/pull/403
    // // Failed to parse source map from '.map' file: Error: ENOENT: no such file or directory, open '.map' file
    "sourceMap": true,
    "inlineSources": true
  },
  "include": ["src/**/*.ts"],
  "exclude": []
}