My first tsconfig.json source: https://github.com/caki0915/my-awesome-greeter/blob/master/tsconfig.json

tsconfig.json

{
  "compilerOptions": {
    "target": "es5",
    "module": "commonjs",
    "declaration": true,
    "outDir": "./lib",
    "strict": true
  },
  "include": ["src"],
  "exclude": ["node_modules", "**/__tests__/*"]
}