tsconfig.json

{
  "compilerOptions": {
    "rootDir": "src",
    // "outDir": "out",
    "lib": ["es2020", "dom", "dom.iterable"],
    "module": "commonjs",
    "target": "es2020",
    "declaration": true,
    "sourceMap": true,
    "strict": true /* enable all strict type-checking options */,
    "moduleResolution": "node",
    "noFallthroughCasesInSwitch": true /* Report errors for fallthrough cases in switch statement. */,
    "esModuleInterop": true,
    "incremental": true, // default is true when composite: true
    "composite": true,
    "useDefineForClassFields": true,
    "allowJs": false,
    "skipLibCheck": true,
    "allowSyntheticDefaultImports": true,
    "resolveJsonModule": true,
    "noUnusedParameters": false,
    "noUnusedLocals": false,
    "isolatedModules": true,
    "noEmit": true, // because esbuild will emit the output (in bundle form)
    "jsx": "preserve"
    // "jsxFactory": "h",
    // "jsxFragmentFactory": "Fragment"
  }
}