tsconfig.json

{
  "compilerOptions": {
    "alwaysStrict": true,
    "declaration": true,
    "esModuleInterop": true,
    "importHelpers": true,
    "jsx": "react",
    "lib": ["dom", "esnext"],
    "module": "esnext",
    "moduleResolution": "node",
    "noFallthroughCasesInSwitch": true,
    "noImplicitAny": true,
    "noImplicitReturns": true,
    "noImplicitThis": true,
    "noUnusedLocals": false,
    "noUnusedParameters": true,
    "resolveJsonModule": true,
    "sourceMap": true,
    "strict": true,
    "strictFunctionTypes": true,
    "strictNullChecks": true,
    "strictPropertyInitialization": true,
    "target": "es5"
  }
}