Boards

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Demos

Focused single-feature reproducers. Each tile is tagged with its minimum svelte-realtime version requirement.

19 / 19

^0.5
Idempotency under double-click

Five rapid RPCs, one effect. live.idempotent.
^0.5
Reconnect-resume with no flicker

Drop network 10s, reconnect, no refetch. Session resume + replay buffer.
^0.5
Chat rooms with presence + denials

live.room bundles messages and presence; live.idempotent on send; FORBIDDEN banner on the members-only room.
^0.5
Optimistic mutate with rollback

rpc.createOptimistic + force-fail toggle. Spam x5 with force-fail on; placeholders roll back independently.
^0.5
Subscribe denials with org switcher

Two orgs (Acme / Globex), one identity cookie. Cross-org subscribes return FORBIDDEN at the wire gate.
^0.5
Admission-shedding control panel

Live platform.pressure readout + sparkline + load generator + shed log.
^0.5
Deterministic chaos

Seed + drop rate, fully reproducible. Same inputs, same green/red pattern.
^0.5
Push, reply, schedule

live.push request/reply across users, cluster registry wiring, and a 6-field live.cron tick draining the schedule queue.
^0.5
Top-K leaderboards: four windows, one config

live.aggregate({ windows }) with sliding, tumbling, and lifetime slices in parallel. Speed slider + bias controls drive the visual diff between window types.
^0.5
Newsroom: cron + windowed aggregate + derived + webhook

Four primitives in one page. live.cron firehose feeds live.aggregate({ windows }); live.derived tracks stats; HMAC-signed Publish form round-trips through live.webhook.
^0.5
Jobs: durable task runner with fence + retry + force-takeover

Postgres-backed createTaskRunner with Redis fence, retry policy, idempotency cache, and force-takeover. live.cron tick polls the table and fans out the row list + status counts.
^0.5
Cluster cron: one leader, one tick

Redis-backed leader election visualised. createLeader + live.configureCron({ leader }) gate a 1Hz live.cron so it fires once cluster-wide instead of once per worker.
^0.5
Upload: streaming uploads with content-addressed dedup

Streaming file uploads via live.upload. SHA-256 chunk hashes go through redis/idempotency so re-uploads skip storage; live.notify({ userId }) fires a fire-and-forget push to the same user's other tabs when a file lands.
^0.5
Auctions: deadline-bounded bid race

List a lot, server fans out live.push to every other tab in parallel, Promise.allSettled collects every reply by the deadline. Each accepted bid ctx.publishes 'updated' on the active stream so the waterfall fills in real time.
^0.5
Schema evolution: subscribe-time migrate hooks

One stream at version: 2 with migrate: { 1: v1ToV2 }. Two panels: a normal subscribe and one via subscribeAt(stream, { schemaVersion: 1 }) from svelte-realtime/test-client - the wire envelope claims v1, the server runs migrate[1] end-to-end, the migrated badge flips back to loader on each live publish.
^0.5
Flash sales: atomic inventory under contention

Three products, limited stock, multi-tab race. live.lock({ key, maxWaitMs }, ...) serializes per-item buys FIFO so stock never goes negative; bursts past the bound surface as LOCK_TIMEOUT. Coupon claim rides live.idempotent keyed on userId for one-per-user enforcement.
^0.5
Pagination: cursor-based load-more

A log feed with 200 entries served in pages of 25. Loader returns { data, hasMore, cursor }; client store exposes loadMore(). Live 'created' publishes merge into the visible list regardless of which pages have been loaded.
^0.5
Effects: server-side reactive side effects

An orders stream's publishes trigger a live.effect(['orders'], handler) that fans out to an audit feed and a notifications feed. Three streams in one page; the effect handler is fire-and-forget.
^0.5
Reconnect: three-tier gap fill via delta.fromSeq

A 1Hz event ticker; tab unsubscribes mid-flight; on resubscribe the server's bounded replay buffer covers short gaps and delta.fromSeq(sinceSeq) bridges to the durable store for older gaps. Each event is tagged with the tier that delivered it.