tsconfig.json

{
  "include": ["src/**/*"],
  "exclude": ["node_modules", "**/*.spec.ts"],
  "compilerOptions": {
    "lib": ["es2018", "dom", "esnext.asynciterable"],
    "target": "es5",
    "module": "commonjs",
    "declaration": true,
    "moduleResolution": "node",
    "outDir": "./dist",
    "sourceMap": true,
    "noImplicitAny": false,
    "emitDecoratorMetadata": true,
    "experimentalDecorators": true,
    "allowSyntheticDefaultImports": false,
    "downlevelIteration": true
    // "strict": true,
    // "noImplicitAny": true,
    // "strictNullChecks": true,
    // "strictFunctionTypes": true,
    // "strictPropertyInitialization": true,
    // "noImplicitThis": true,
    // "alwaysStrict": true,
    // "noUnusedLocals": true,
    // "noUnusedParameters": true,
    // "noImplicitReturns": true,
    // "noFallthroughCasesInSwitch": true,
    // "esModuleInterop": true
  }
}