Introduce a minimum-supported-client gate so a future incompatible wire change can turn away installed builds too old to speak it, cleanly, instead of letting them crash on decode. It rides the outermost stable layer (an HTTP header), never the FlatBuffers payload. Gateway: - New internal/clientver: dependency-free parse + compare of the leading MAJOR.MINOR.PATCH (a git-describe suffix is tolerated). - GATEWAY_MIN_CLIENT_VERSION config (empty => gate dormant; validated at load). - connectsrv checks the X-Client-Version header before decoding the payload: Execute returns result_code="update_required" (before the registry lookup), Subscribe returns FailedPrecondition. It fails open on an absent or garbled header — the header is a client-controlled compatibility signal, not an access control. Client: - Attach X-Client-Version on every call. - A terminal update.svelte.ts store + a non-dismissable UpdateOverlay (native opens VITE_STORE_URL, web reloads); retry.ts maps FailedPrecondition to the update_required sentinel; a mock __update hook drives the e2e. Wire-additive and contour-safe: no FBS/proto regen, no schema migration; the gate stays dormant until GATEWAY_MIN_CLIENT_VERSION is deliberately set, so web / VK / Telegram behaviour is unchanged. The silent reconciliation seam is deferred to the offline-first work (its only caller). Tests: Go clientver/config/connectsrv gate tests, retry.test.ts, Playwright update.spec.ts.
scrabble-ui
Pure-HTML5 game client — plain Svelte 5 (runes) + TypeScript + Vite, no
SvelteKit. Talks to the gateway over Connect-RPC + FlatBuffers; embeddable in
platform webviews and packageable to native via Capacitor.
The playable slice: sign in (guest / email), the "my games" lobby, auto-match, the board (place tiles by drag or tap, pass, exchange, resign), hint, word-check + complaint, per-game chat and nudge, the live in-app stream, i18n (en/ru), theme, and the profile. Social surfaces add friends/blocks (with one-time friend codes), friend-game invitations, profile editing + email binding, the statistics screen, the lobby notification badge, and the in-game history + GCG export (share or download, finished games only).
Scripts
pnpm install
pnpm start # mock mode (VITE_MOCK): lobby -> game with no backend, :5173
pnpm dev # against a running gateway (Vite proxies /scrabble.edge.v1.Gateway -> :8081)
pnpm check # svelte-check / tsc
pnpm test:unit # Vitest (pure logic + FlatBuffers codec)
pnpm test:e2e # Playwright smoke against the mock
pnpm build # static bundle into dist/ (prod app ~97 KB gzip JS; per-chunk budget: scripts/bundle-size.mjs)
pnpm codegen # regenerate src/gen from edge.proto + scrabble.fbs (dev-time)
GATEWAY_URL overrides the dev proxy target; VITE_GATEWAY_URL sets the runtime
gateway origin for a packaged (non-proxied) build. VITE_TELEGRAM_BOT_ID
enables the "Link Telegram" web sign-in (the Login Widget) — inert until the site
domain is registered with BotFather (/setdomain); VITE_TELEGRAM_LINK is the
friend-invite Mini App link for the single bot (full URL https://t.me/<bot>/<app>).
VITE_TELEGRAM_GAME_CHANNEL_NAME is the "Play in Telegram" link shown on the landing page.
The build has two entries: the game SPA (index.html, served at /app/ and
/telegram/) and a lightweight landing page (landing.html, served at /).
How it talks to the gateway
A single Connect Execute(message_type, payload) carries every unary op; the request
and response bodies are FlatBuffers tables (pkg/fbs/scrabble.fbs) in payload.
The session token rides in Authorization: Bearer; a domain failure comes back in
result_code. Subscribe is the live event stream; its game events carry a state delta
that lib/gamedelta.ts applies to the per-game cache (lib/gamecache.ts), so a move renders without
a follow-up game.state (a gap falls back to a refetch). lib/transport.ts is the real
client; lib/mock/ is an in-memory fake selected by MODE === 'mock' (and tree-shaken
out of production). Both speak the plain lib/model.ts types via lib/codec.ts.
No board on the wire: StateView is a summary + rack only, so the client
reconstructs the 15×15 board by replaying the decoded move journal (game.history).
The play loop is alphabet-agnostic: the rack and the play / exchange /
word-check requests carry alphabet indices, and the client caches each variant's
(index, letter, value) table — sent once behind StateRequest.include_alphabet — in
lib/alphabet.ts, rendering the rack and blank chooser from it. Premium squares
(lib/premiums.ts) stay a client-side geometry map ported from
scrabble-solver/rules/rules.go (pinned by a Vitest parity test); tile values and the
alphabet now come from the server table (their parity lives in the Go engine.AlphabetTable
test). Board, tiles and effects are pure CSS + Unicode — no image/font/SVG assets.
Codegen
src/gen/ is committed; CI builds it, it is not regenerated there (the same model
as the Go committed jet/fbs output). pnpm codegen runs flatc --ts on
../pkg/fbs/scrabble.fbs and buf generate (protoc-gen-es) on the edge proto. Needs
flatc 23.5.26 and buf on PATH.
Theming
Design tokens are CSS custom properties (src/app.css); light/dark follows
prefers-color-scheme or an explicit choice in Settings. The token system is
Telegram-themeParams-ready (lib/theme.ts) — a Mini App can override the tokens at
runtime; the Telegram SDK itself is wired in the Telegram stage.
Layout
src/
lib/ model, client facade, transport (+ mock), codec, board replay,
placement state machine, premiums (geometry), alphabet cache, stats, share,
i18n, theme, session, router, app store
components/ Header, Menu (+ badge), Modal, Toast, TabBar, Screen
screens/ Login, Lobby, NewGame, Profile, Settings, About, Friends, Stats
game/ Game, Board, Rack, Controls, MakeMove, Chat
gen/ committed edge codegen (FlatBuffers + Connect)
e2e/ Playwright smoke + social specs (mock)