tsconfig.json

{
  "compilerOptions": {
    "target": "es2017",
    "module": "commonjs",
    "declaration": true,
    "outDir": "./built/",
    "removeComments": true,
    "strict": true,
    "strictFunctionTypes": true,
    "strictNullChecks": true,
    "experimentalDecorators": true,
    "noImplicitReturns": true,
    "esModuleInterop": true,
  },
  "include": [
    "src/**/*",
  ],
  "exclude": [
    "node_modules",
    "test/**/*",
  ]
}