End-to-end flow
Follow one action through the whole system, step by step.
Pick a tab and press Play. Each step lights up the nodes involved and narrates what moves: a guest drawing that never leaves the device, a signed-in save through the HTTP server into the database, or a room edit travelling from one browser through the socket, Redis, and the flush worker into Postgres while cursors and previews take a separate path that is never stored.
Step 1 of 4 — Draw. Strokes become elements in the Editor.
Sources: apps/web/src/lib/sync/roomSync.ts, apps/web/src/lib/sync/outbox.ts, apps/web/src/lib/sync/commits.ts, apps/web/src/lib/persistence/indexedDb.ts, apps/http-server/src/routes/scenes.ts, apps/http-server/src/routes/rooms.ts, apps/ws-server/src/server.ts, packages/backend-common/src/collaboration.ts, packages/redis/src/index.ts, apps/flush-worker/src/index.ts, packages/common/src/sync.ts (documented at commit b0026d9)