# Tech Stack Decisions — Unit 1: Project Scaffold & Infrastructure

## Existing Stack (from ZIP example + requirements)
All prior choices retained:
- **Vite 6** — Build tool
- **React 18** — UI library
- **TypeScript 5** — Type safety
- **TanStack Router v1** — File-based routing (replaces React Router)
- **Tailwind CSS v4** + **shadcn/ui** — Styling & components (primary color `#ac0000`)
- **pnpm** — Package manager
- **ESLint + Prettier** (4-space indent) — Formatting

---

## New: Testing Framework

| Decision | Choice | Rationale |
|----------|--------|-----------|
| Test runner | Vitest | Native ESM, fast, Vite-native, excellent TypeScript support |
| Component testing | React Testing Library | Industry standard for React; focuses on user behavior |
| API mocking | MSW (Mock Service Worker) | Works in browser + Node; realistic network layer for auth flows |
| Test command | `pnpm test` | Consistent with existing pnpm scripts |

---

## New: Internationalization

| Decision | Choice | Rationale |
|----------|--------|-----------|
| i18n library | react-i18next + i18next-browser-languagedetector | Most popular React i18n solution; automatic language detection |
| Translation files | JSON under `public/locales/{en,nl}/` | Standard, easy to edit, works with Vite static assets |
| Language switcher | Custom component in user menu | Keeps UI consistent with shadcn/ui |

---

## New: Environment Configuration

| Decision | Choice | Rationale |
|----------|--------|-----------|
| Env variables | Vite `import.meta.env.VITE_*` | Official, type-safe, exposed to client |
| Example file | `.env.example` (committed) | Documents required variables for new developers |
| Local overrides | `.env.local` (gitignored) | Follows Vite + dotenv conventions |

---

## Explicitly NOT included (per answers)

- No Sentry / OpenTelemetry in scaffold
- No husky + lint-staged pre-commit hooks
- No WCAG 2.2 AA/AAA a11y requirements beyond basic keyboard support
- No hard bundle-size budget (optimize for smallest possible)

---

## appsettings / env additions (frontend only)

`.env.example` (committed):
```env
VITE_API_BASE_URL=http://localhost:5000
```

`.env.local` (developer only, gitignored):
```env
VITE_API_BASE_URL=http://localhost:5000
```

No changes needed to backend `appsettings.json` for Unit 1.