EtherCalc

EtherCalc is a real-time, multi-user spreadsheet server. This documentation covers the TypeScript rewrite that runs on Cloudflare Workers with Durable Objects, D1, KV, and R2 — and can also be self-hosted with a standalone workerd container.

Quick start

git clone https://github.com/audreyt/ethercalc
cd ethercalc && bun install
bun run --cwd packages/worker dev   # wrangler dev on http://127.0.0.1:8787

Open http://127.0.0.1:8787/_new to create a sheet.

What changed

Concern	Legacy (Node + Redis)	New (Workers)
HTTP	Express 3 / zappajs	Hono on Workers
Live state	in-memory + Redis	Durable Object per room
Realtime	socket.io 0.9/1.x	native WebSocket (JSON) + legacy shim
Self-host	Node + Redis compose	standalone workerd image

The public HTTP API is preserved byte-for-byte where deterministic. WebSocket clients speak raw JSON at /_ws/:room; the /socket.io/* shim remains for external embeds.

Next steps

• User guide — formulas, forms, tips (replaces the old GitHub wiki)
• Architecture — components, request flow, storage model
• Self-hosting — Docker, Helm, nginx hardening
• Oracle testing — equivalence fixtures against the legacy oracle