**box-box** is an F1 dashboard in Go with two frontends sharing the same data layer: a Bubble Tea TUI and a web app (`--web` flag) — a Go HTTP server in `internal/web/` serving a React SPA plus a REST/SSE API. It shows live timing, standings, race calendar, driver telemetry, track maps, and race replay — sourced from the OpenF1 API and a local domain SQLite DB filled by the ingestion CLI.
Each tab is a sub-model with `Init()`, `Update(msg)`, `View()`. The root `AppModel` in `app.go` holds all sub-models and routes messages by type. All state changes are message-driven — no direct mutation.
`box-box --web` starts an HTTP server (default `:8080`) with three surfaces:
- **REST API at `/api/v1/...`** — Handlers in `internal/web/api.go` wrap `OpenF1Client`; navigation/race-hub endpoints read the domain DB via `internal/query` (empty responses if the DB is missing). `?source=openf1|local|auto` picks the data source where supported. Register routes in `routes()` in `server.go` — Go ServeMux longest-prefix matching means more specific paths (e.g. `/api/v1/laps/comparison`) must be registered before their prefixes.
- **SSE live stream** — `internal/web/live.go` runs a background SignalR connection to the official F1 feed (exponential-backoff reconnect; disabled with `BOXBOX_DISABLE_LIVE=1`). An `SSEHub` broadcasts snapshots to browsers on `/api/v1/live/stream`, with `/api/v1/live/state` for the initial snapshot and a 20s heartbeat. `LiveTimingPage.tsx` consumes it; parsing helpers live in `frontend/src/lib/live.ts`.
- **Embedded SPA** — Static file server with SPA fallback to `index.html`. Prefers a `frontend/dist` directory found by walking up from cwd (so `npm run build` output is served without rebuilding Go); otherwise serves the legacy assets embedded via `//go:embed assets`.
- **Championship hub** — `/api/v1/championship/hub` aggregates official standings with derived stats (wins, podiums, poles, last-5 form, teammate head-to-head) and per-round cumulative points, computed from all season race results.
Frontend dev loop: run `go run cmd/main.go --web` and `npm run dev` in `frontend/` — Vite proxies `/api` to the Go server.
- **New tab**: Create model in `internal/ui/`, add to `AppModel` struct in `app.go`, add tab constant, implement `Init/Update/View`, handle message routing in `app.go Update()`
- **New API endpoint**: Add method to `openf1.go`, add response struct to `types.go`, set cache TTL in the method
- **New message type**: Define in `messages.go`, handle in relevant model's `Update()`
- **New keybinding**: Define in `keys.go`, handle in relevant model's `Update()`
- **New styles**: Add to `styles.go`, reference F1 palette constants
- **New web page/route**: Create page in `frontend/src/pages/`, register route in `frontend/src/router.tsx`, add nav link in `frontend/src/components/Nav.tsx`, add fetchers to `src/api.ts` and payload types to `src/types.ts`, add a test in `frontend/src/test/`
- **New web API endpoint**: Add handler in `internal/web/api.go` (or a new file in `internal/web/`), register it in `routes()` in `server.go` (mind prefix ordering), add a handler test alongside (see `championship_hub_test.go`)
- Go: tests in `openf1_test.go` hit the real OpenF1 API and use `skipOnRateLimit(t, err)` to skip on HTTP 429 (require internet). `internal/web` handler tests run offline.
- Frontend: Vitest + Testing Library in `frontend/src/test/` (`npm run test` inside `frontend/`).
- E2E/visual: Playwright at repo root (`npm run test:e2e`, `npm run test:visual`). Configs seed a temp domain DB and start the Go server with `BOXBOX_DISABLE_LIVE=1` plus a Vite dev server — no manual setup needed.
