Selecting thumbs or flipping SINGLE <-> ALL THUMBS on a roll whose captions wrap to different heights crashed the shelf with React #185 ("Maximum update depth exceeded") and left the screen blank. useWallWindow read the step from one row to the next off the rows the window itself had drawn, and the average of a run of rows moves as the run grows: `to` traded places with a sum a row away — 35, 40, 35, 40, three milliseconds apart — every pass a render, until React gave up. The step is taken once per column count and kept, re-read when the wall re-columns, which is the only thing that changes a card own height (a caption wraps at the width it is given). The window is a function of the scroll and nothing else, so it settles. Reproduced with the storm probe against a 3000-frame roll of unevenly named frames: before, blank at round 1 with #185; after, 12 rounds of hard SINGLE/ALL THUMBS toggling plus a round trip through the studio — no error, no blank screen, and D18 unchanged (tile CHANGED, the shelf raising the studio frame 4px off centre, the studio link opening the same frame).
RecipesCam web — self-contained stack
A Docker-hosted web build of RecipesCam. Everything it needs is in this folder: move it to another machine, run two commands, and the app is up. It does not need the React Native project around it.
cp .env.example .env
docker compose up -d --build
# → http://localhost:8090
What runs where
| Service | Image | Role |
|---|---|---|
frontend |
nginx:1.27-alpine (built by frontend/Dockerfile) |
Static SPA + /api/ reverse proxy |
api |
node:22-slim (built by backend/Dockerfile) |
Accounts + saved recipes, SQLite on ./data |
frontend resolves api through Docker's embedded DNS and proxies /api/* to
it — that is why the API container is named api and why it is not published on
the host. Only ${WEB_PORT:-8090} is exposed.
Photos never leave the browser. The CanvasKit render pipeline (grade, frame, watermarks, JPEG encode) runs in the visitor's tab; the API only stores recipes as JSON.
Layout
docker-compose.yml the stack
.env.example WEB_PORT
data/ SQLite (created on first run, gitignored)
backend/ Fastify + better-sqlite3 API, own Dockerfile
frontend/ Vite + React + CanvasKit SPA, own Dockerfile + nginx.conf
shared/ vendored copies of the app's types + utils (see below)
src/engine/ skiaShim.ts (CanvasKit) + exportEngine.ts (render pipeline)
+ session.ts (localStorage/IndexedDB studio persistence)
Vendored files
frontend/shared/{types/index.ts,utils/*.ts} are byte-identical copies of
src/types/index.ts and ten src/utils/*.ts files from the React Native
project (@shopify/react-native-skia is aliased to src/engine/skiaShim.ts in
vite.config.ts + tsconfig.json, so those files compile unchanged):
cinemaShader colorUtils defaultRecipes exifWrite frameUtils jpegDpi
paramDefs recipeShare skiaImage toneShader.
The landing page needs no CDN: frontend/public/assets/fonts/*.woff2 are the
seven self-hosted faces behind the three font groups the Themes menu offers
(Plus Jakarta Sans / Inter / JetBrains Mono, Fraunces / Be Vietnam Pro /
Courier Prime, Be Vietnam Pro / Space Mono — all SIL OFL, pulled from Google
Fonts, vietnamese + latin + latin-ext subsets), and
frontend/public/assets/samples/s*.jpg are the six placeholder negatives the
film strip, preset tester and QR card show (swap them for real graded stills
whenever we have them). Its one foreign request is the QR image from
api.qrserver.com, which degrades to an empty slot offline.
When the app changes one of them, copy it back in — the renderer is only "parity" for as long as these stay in sync:
cd <repo>/docker/frontend/shared/utils
cp <repo>/src/utils/<name>.ts .
Operations
docker compose logs -f api # API log
docker compose restart api # after backend/src changes (rebuild: --build)
docker compose down # stop; ./data survives
Backup is the ./data folder — that is the whole database.
Checks
curl -s http://localhost:8090/api/health # {"ok":true}
curl -sI http://localhost:8090/ # 200, index.html
Then open the UI, drop a photo in, and confirm the preview shows the picture and
EXPORT downloads a JPEG that opens. The preview going solid black while the
export still reports a plausible size is the one failure mode worth knowing: it
means the CanvasKit GPU surfaces lost their shared GrDirectContext (see
frontend/src/engine/skiaShim.ts), and with no GPU the raster fallback renders
the same pipeline correctly, just slower.