tsconfig.json

{
  "compilerOptions": {
    // ── Environment & latest features ────────────────────────────────────
    "lib": ["ESNext"],
    "target": "ESNext",
    "module": "Preserve",
    "moduleDetection": "force",
    "jsx": "react-jsx",
    "allowJs": true,

    // ── Bundler mode ─────────────────────────────────────────────────────
    "moduleResolution": "bundler",
    "allowImportingTsExtensions": true,
    "verbatimModuleSyntax": true,
    "noEmit": true,

    // ── Full strict mode — every single strict flag ON ───────────────────
    "strict": true,
    "strictNullChecks": true,
    "strictFunctionTypes": true,
    "strictBindCallApply": true,
    "strictPropertyInitialization": true,
    "noImplicitAny": true,
    "noImplicitThis": true,
    "alwaysStrict": true,
    "useUnknownInCatchVariables": true,

    // ── Additional strictness ────────────────────────────────────────────
    "exactOptionalPropertyTypes": true,
    "noUncheckedIndexedAccess": true,
    "noImplicitOverride": true,
    "noPropertyAccessFromIndexSignature": true,
    "noUnusedLocals": true,
    "noUnusedParameters": true,
    "noFallthroughCasesInSwitch": true,
    "noUncheckedSideEffectImports": true,
    "strictBuiltinIteratorReturn": true,
    "isolatedModules": true,
    "forceConsistentCasingInFileNames": true,

    // skipLibCheck is load-bearing, not incidental (issue #429): with it off,
    // tsc6 reports ~177 errors, all inside third-party .d.ts files (elysia dist
    // types do not compile under TS 6 stricter generics checks) and zero in
    // first-party code. Re-probe with
    // `tsc6 --noEmit --skipLibCheck false` before flipping this.
    "skipLibCheck": true
  }
}