Jazz examples and real-world benchmarks

A Next.js app with Better Auth sign-in, where a room's creator admits or removes members and only members can read or post. Messages carry inline attachments and are created local-first. Its benchmarks cover what a chat does constantly: opening a private room through its membership policy, sending messages, scrolling back, unread rooms by recent activity, a new message while many rooms are open, and resuming a caught-up client.

• Create a room and admit a bandmate
• Send a message with an inline attachment
• Removing a member stops their later writes

A crew prepares shows together: each show has a board of stage-prep tasks with discussion and an activity log, and every crew member's dashboard mounts dozens of live department lists at once. Every write lands locally first and syncs in the background. Crews only see their own shows, enforced by inherited row-level permissions, and tasks can be archived and restored.

• Two crew members add and check off tasks and see each other's changes live
• Moving a card to Done updates every open filtered view
• A dashboard mounts dozens of live department lists at once
• Another crew's shows are invisible, enforced by inherited permissions

A band's shared notebook: members write pages, track issues, and belong to workspaces. A member may read their own pages plus those of every workspace they were admitted to. Its benchmarks load the newest 50 pages of a 100,000-page notebook under an explicit allow-all policy, an owner-only policy and the own-or-workspace policy, so the difference is the price of authorization.

• Show my pages, newest first
• Show my workspace's pages and issues
• Keep the page list live as pages change

A Vue app for planning a band's tour, with the schedule drawn on a dot-art globe. Members see the full calendar; the public sees confirmed dates only. Both are ordered, bounded three-week itinerary reads that include each stop's venue.

• The tour's stops are drawn on the globe
• Members see every date; the public calendar shows confirmed dates only

Bandmates edit a shared pattern together, watch its transport state and see who else is around. It makes hard local-first shapes concrete: an ordered, windowed step grid with many small subscriptions, concurrent edits to nearby and identical steps, and editor and viewer roles on one shared session.

• Two bandmates toggle steps in the same pattern at once
• Go offline, keep editing, and reconnect
• A viewer's edit is refused

The durable data a tldraw-like canvas needs, without tying it to a renderer: canvases, ordered layers, shapes, asset metadata and checkpoints. Layers, canvas, cursors, assets and checkpoints are independently subscribed, so a stream of cursor updates never re-runs the whole canvas query.

• Two editors add shapes to the same canvas
• Cursors move live without touching history
• Offline edits replay to peers after reconnecting

Albums are browsed in a CoverFlow view and collected into shared playlists. Audio is uploaded as streamed bytes, and invitations grant listener or editor access to a playlist. Concurrent additions from two people converge on the same list.

• Invite a friend to listen, or to edit
• Two people add tracks to one playlist at once
• Offline additions flush on reconnect

Uploads stream a browser File directly into Jazz, and a folder lists each file's name, type and size without loading any file contents. A cancelled upload publishes nothing, and a retry starts clean.

• Drop a large file and watch it stream in
• Browse a folder without downloading its files

The shop front of the Jamazon instrument store: browse and search a large catalogue, keep a cart that follows you across devices, and check out against live stock. It shares its data with the Jamazon Warehouse operations console.

• Browse and search the catalogue
• A cart that follows you across devices
• Check out against live stock levels

Warehouses, districts, stock, customers, orders and payments, with multi-row checkout, ordered and bounded operational reads, local-first retry, and an idempotent hand-off to external effects. Anyone can watch stock and orders; only a warehouse's operator can change them.

• Place an order that reserves stock across several rows
• Watch stock levels update live on the console

A provider-free agent harness that records a conversation, streams a long assistant turn, logs tool invocations and keeps uploaded audio as bytes. A deterministic fake agent makes the whole flow run without an API key.

• A long assistant reply streams in as it's written
• Tool calls and attachments are part of the transcript

BigLabel is a Next.js app with Better Auth sign-in, where each organization manages its artists and releases under admin-checked membership policies. It exercises what SaaS apps do all day: tenant-scoped lists, relations, cold loads and bulk imports.

• Sign in and land in your own organization
• Invite teammates and assign roles
• Import a catalogue of releases in bulk