tsconfig.json

{
  "compilerOptions": {
    "lib": ["dom", "es6","es2015.promise"],
    "target": "ES2015",
    "module": "es2015",
    "moduleResolution": "node",
    "outDir": "./lib",
    "declaration": true,
    "strict": true,
    "allowSyntheticDefaultImports": true,
    "importHelpers": true,
    "jsx": "react",
    "alwaysStrict": true,
    "sourceMap": true,
    "forceConsistentCasingInFileNames": true,
    "noFallthroughCasesInSwitch": true,
    "noImplicitReturns": true,
    "noUnusedLocals": true,
    "noUnusedParameters": true,
    "noImplicitAny": true,
    "noImplicitThis": true,
    "strictNullChecks": true,
    "strictFunctionTypes": true,
    "preserveConstEnums": true,
    "experimentalDecorators": true,
    "emitDecoratorMetadata": true,
    "skipLibCheck": true,
    "esModuleInterop": true,
  },
  "include": ["src"],
  "exclude": ["node_modules", "**/__tests__/*"]
}