Stack guides / Realtime
Live updates, chat, presence and collaborative editing.
6 options. Free tiers, catches and prices checked by hand on 2026-10-27; each one links to its sources.
A hosted realtime pub/sub platform for chat, presence and live updates.
Best for: Pub/sub, presence and chat with a generous free message allowance. Skip it if: You want flat, usage-free pricing.
`ably init` installs Ably Agent Skills into Claude Code, Cursor, VS Code and Windsurf; llms.txt.
Free
200 peak connections is the real ceiling.
Stateful serverless objects with WebSockets and SQLite on Cloudflare; PartyServer is the successor to PartyKit.
Best for: Multiplayer rooms and chat using hibernating WebSockets. Skip it if: You want a hosted realtime API with no server code.
Official Cloudflare MCP; PartyServer/PartySocket libraries are ISC-licensed.
Workers Free (SQLite-backed only)
Past any free limit, those operations fail until the 00:00 UTC reset.
Workers Paid $5/mo (1M requests, 400K GB-s included)
Checked 2026-10-27: developers.cloudflare.com, github.com, partykit.io
Google’s hosted JSON database that syncs data to clients in realtime.
Best for: Simple live sync for Firebase mobile apps. Skip it if: You need relational queries.
Official Firebase MCP server in firebase-tools.
Spark
Only 100 simultaneous connections; on Blaze it’s $5/GB stored and $1/GB downloaded.
Blaze pay-as-you-go
Checked 2026-10-27: firebase.google.com, firebase.google.com
Hosted infrastructure for multiplayer editing, presence, comments and notifications.
Best for: Figma- or Notion-style collaboration in React apps. Skip it if: You need production self-hosting (Enterprise add-on; the AGPL-3.0 server release targets local dev).
liveblocks-mcp-server repo; llms.txt.
Free
Each meter is hard-capped (the feature pauses until next cycle) and Liveblocks branding is required.
Pro $30/mo ($25 annually), includes $30 usage
Checked 2026-10-27: liveblocks.io, liveblocks.io
A hosted pub/sub WebSocket API for realtime events.
Best for: Simple server-to-browser event pushes. Skip it if: You need more than 100 live users for free.
Sandbox
100 concurrent connections caps it at prototype scale.
Startup $49/mo (1M messages/day, 500 connections)
Checked 2026-10-27: pusher.com
Supabase’s WebSocket service for broadcast, presence and Postgres change streams.
Best for: Live updates, presence and chat in Supabase apps. Skip it if: You expect hundreds of simultaneous users on Free.
Official Supabase MCP (mcp.supabase.com); llms.txt.
Free
The project pauses after 1 week of inactivity.
Pro $25/mo (500 connections, 5M messages)
Checked 2026-10-27: supabase.com, supabase.com
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