Add a per-game rule chosen on New Game for Russian variants (default off = the
single-word rule; on = standard Scrabble). Off, only the main word along the play
direction is validated and scored; perpendicular cross-words are ignored,
including in robot move generation. The rule rides every create and enqueue
request and joins the matchmaking key, so games and auto-match stay one uniform
path; "Russian-only" is a UI affordance (English always sends standard and shows
no toggle).
- Engine: consume scrabble-solver v1.1.0's PlayOptions{IgnoreCrossWords}, threaded
through engine.Options.MultipleWordsPerTurn -> playOpts() into validate, score
and generate.
- Backend: thread the flag through game CreateParams/Game + store (games column),
lobby InvitationSettings + invitation row, and the matchmaker queue key (variant
+ rule); persisted, so a rebuilt-from-journal game keeps it. Baseline migration
gains multiple_words_per_turn (DB not versioned); jet regenerated.
- Edge: multiple_words_per_turn added to the EnqueueRequest / CreateInvitationRequest
FlatBuffers tables (Go + TS regenerated) and threaded through the gateway.
- UI: a "Multiple words per turn" toggle on New Game, shown for Russian variants
only (auto-match and friend invite), default off; English silently sends standard.
- Tests: backend engine/matchmaker; UI unit (gating) + Playwright e2e (solver
corner-case + GCG fixtures ship in v1.1.0). Docs + PRERELEASE tracker updated.
A single tile that only extended a word perpendicular to the client-declared
direction was rejected: the UI always sent dir=H for one-tile plays (the
dirOverride/Controls toggle was orphaned in the Stage 7 game rework), so placing
"А" above "БАК" to form "АБАК" failed the solver's main-word-length check even
though the word is in the dictionary.
Make the backend infer a play's orientation from the placed tiles and the board
(internal/engine.resolveDirection): two or more tiles by the line they share, a
lone tile by the axis it abuts (longer word wins, horizontal on a tie). Direction
becomes an output, not an input: drop dir from the SubmitPlay/Eval wire requests
and add it to EvalResult. Journal replay keeps trusting the stored "H"/"V"
(SubmitPlayDir) so a rebuilt game matches the one committed.
UI: stop computing/sending direction; the preview now shows the words a move
forms with its total score (game.previewWords); the make-move control is disabled
until the play is confirmed legal; the "your turn" label hides while tiles are
pending. Delete the orphaned Controls.svelte.
Regenerate the FlatBuffers bindings (Go + TS) and update the gateway transcode
and the loadtest edge client to the new contract. Bake the decision into
ARCHITECTURE.md (§5/§9.1), FUNCTIONAL.md (+ _ru) and the backend README.
A practical single-host ordering guide — CPU cores, RAM, disk at three tiers —
grounded in the R7 profile (~5.5 cores / ~2.5 GiB peak at 500 players) and the
measured on-disk footprint (images ~2.4 GB; Tempo 3.1 GB at 72 h; the game DB
23 MiB and growing). Notes which knobs move disk (Tempo/Prometheus retention,
Postgres growth) and that the gateway scales horizontally past one host.
- loadtest/REPORT-R7.md: the final stress-run report — method, the 500-player resource
profile, the agreed tuning, the validation (transport_error 2.49% -> 0.72% at 3 gateway
cores; the burst run showing connection-bound behavior), and the prod-sizing
recommendation for Stage 18.
- loadtest/README.md: per-player transports, --cpus capping, docker_stats (was cAdvisor),
the absolute BACKEND_DICT_DIR for ./loadtest/... , and report links.
- docs/TESTING.md + docs/ARCHITECTURE.md: observability now uses the otelcol docker_stats
receiver (cAdvisor removed); links to both trip reports.
- CLAUDE.md: repo-layout line reflects docker_stats + per-service limits.
- PRERELEASE.md: R7 marked done in the tracker + heading; a Refinements entry recording
the decisions, findings, applied tuning and validation.
This is the final pre-release hardening phase; Stage 18 (prod cutover) is next.
Each virtual player now builds its own edge.Client (its own h2c connection
carrying both the Subscribe stream and the Execute calls), instead of every
player multiplexing over a single shared http2.Transport. The R2 trip report
traced the ~14% transport_error on game.state at 500 players to that single
shared transport; per-player connections mirror real clients and isolate the
artifact. The assembly burst and the gateway-hammer each get their own client.
playTurn now reports when a game has finished so playerLoop drops it from the
rotation (slices.DeleteFunc); once no active game remains the player idles while
still holding its stream. This stops secondary ops from hammering game_finished
on already-ended games (the other R2 harness finding).
Ran the moderate early pass (50/200/500, 10 min/step) against the contour: ramped
clean to 500 players, 1.2 M edge calls, 48 870 plays, 2 798 games finished, no
crash/deadlock; cleanup removed all 11 000 seeded accounts. The per-user limiter held
under the gateway-hammer (99.97 % rejected, p99 2 ms).
Top finding: ~14 % transport_error on game.state at 500 players under CPU saturation
(backend/gateway/Postgres each ~1 core), amplified by the harness's single shared
http2.Transport (the harness itself peaked at 86 % of a core on the same host).
Observability finding: cAdvisor yields only the root cgroup on the contour host
(separate XFS /var/lib/docker); per-container metrics captured via docker stats; R7
should adopt the otelcol docker_stats receiver. Full report in loadtest/REPORT-R2.md;
PRERELEASE refinements logged; R2 marked done.
- display-name marker: letters-only 'Zzloadtest' (the editable-name validator
forbids digits/colons), so profile.update resends the seeded name successfully.
- draft.save: rack_order is a string in the backend draft DTO (was sent as []),
fixing the bad_request.
Both confirmed ok against the contour. chat_not_your_turn / nudge_own_turn are
by-design turn gates (backend/internal/social/chat.go), correctly exercised.
New scrabble/loadtest module (the pre-release stress harness): seeds 1000 guest +
10000 durable accounts with pre-created sessions directly in Postgres (token hash
matches backend/internal/session), drives virtual players through the edge protocol
(real 2-4p games assembled via invitations, mid-ranked legal moves generated locally
by the embedded scrabble-solver — the edge carries no board, so the client replays
history), plus nudge/chat/check-word/draft/profile/stats and a gateway-hammer that
verifies the rate limiter. Prints a trip-report summary (per-op latency percentiles,
result codes, live-event tally). Go unit tests cover the pure pieces; the DAWG-backed
move test runs under BACKEND_DICT_DIR.
Contour: add cAdvisor + postgres_exporter + a 'Scrabble - Resources' Grafana
dashboard and the two Prometheus scrape jobs, for the R2/R7 stress-run resource
baseline.
CI: gate ./loadtest/... (path filter + vet/build/test). Docs: TESTING, ARCHITECTURE,
project CLAUDE repo layout.
Ilia Denisov