tsconfig.json

{
  "compilerOptions": {
    "target": "ES2020",
    "useDefineForClassFields": true,
    "module": "ESNext",
    "lib": ["ES2020", "DOM", "DOM.Iterable"],
    "outDir": "dist",
    "skipLibCheck": true,
    "paths": {
      "react": ["./node_modules/preact/compat/"],
      "react-dom": ["./node_modules/preact/compat/"]
    },

    /* Bundler mode */
    "moduleResolution": "bundler",
    // "allowImportingTsExtensions": true,
    "resolveJsonModule": true,
    "isolatedModules": true,
    // "emitDeclarationOnly": true,
    "declaration": true,
    "jsx": "react-jsx",
    "jsxImportSource": "preact",

    /* Linting */
    "strict": true,
    "noUnusedLocals": true,
    "noUnusedParameters": true,
    "noFallthroughCasesInSwitch": true
  },
  "include": ["src"],
  "exclude": ["src/main.tsx"],
  "references": [{ "path": "./tsconfig.node.json" }]
}