tsconfig.json

{
  "compilerOptions": {
    "declaration": true,
    "declarationDir": "./build",
    "allowSyntheticDefaultImports": true,
    "resolveJsonModule": true,
    "sourceMap": true,
    "strict": true,
    "module": "commonjs",
    "target": "es6",
    "moduleResolution": "node",
    "noUnusedParameters": true,
    "esModuleInterop": true,
    "outDir": "build"
  },
  "exclude": [
    "example",
    "build"
  ],
  "watchOptions": {
    // Use native file system events for files and directories
    "watchFile": "useFsEvents",
    "watchDirectory": "useFsEvents",
    // Poll files for updates more frequently
    // when they're updated a lot.
    "fallbackPolling": "dynamicPriority",
    // Don't coalesce watch notification
    "synchronousWatchDirectory": true,
    // Finally, two additional settings for reducing the amount of possible
    // files to track  work from these directories
    "excludeDirectories": ["**/node_modules", "build"]
  }
}