livediagram

A collaborative diagram editor that works without signing in. Open a link, draw, share. Real-time presence, cursors, comments, undo and redo. The canvas never sits behind an auth wall, so the friction to start is "open the link, start drawing."

Live at livediagram.app. MIT-licensed and self-hostable end-to-end.

apps/        marketing site + editor + telemetry dashboard + help centre + community + api + mcp server + router + cli
packages/    shared document model, wire-format types, UI primitives, icon + template catalogues + template previews, help-article registry, the Explorer filter lens, items and the Plan board projection, the api client and agent verbs, the edit-operations engine, document views, the diagram lint, sticky-note photo detection, telemetry client, test fakes, configs
scripts/     repo-wide dev tooling (shared Next.js dev launcher)
docs/        guides, product specs (docs/specs, read these before adding features) and instructions
marketing/   off-site copy + media for listings and promotion (see docs/specs/019-marketing/marketing-assets.md)

Start here

The 30-second tour

• Marketing at / is the pitch and feature tour.
• Editor is the canvas, served at clean routes (/new, /document/<id>, /explorer/...; no /live prefix). Guests get a per-browser identity and full persistence; signed-in users get the same plus cross-device sync. /explorer opens on the Timeline, a day-grouped feed of everything that happened across your documents, teams and account (Timeline); the Activity section beside it lists what is still outstanding for you (open actions assigned to or by you, comment threads you are in) across every document (Activity page). Signed-in users can mirror their Personal Space to their own Google Drive, kept in step both ways while a tab is open (Google Drive mirror).
• API at /api/* is a Cloudflare Worker (REST + WebSocket realtime room per document, backed by D1).
• Telemetry at /telemetry is the public anonymous-events dashboard (off in OSS forks by default).
• Help at /help is the static help centre (guides, feature docs, troubleshooting).
• Community at /community is the public gallery of shared documents: browse, like and copy what people publish (Community).
• MCP at mcp.livediagram.app is a Cloudflare Worker that exposes the document tools to AI clients (Claude and other MCP hosts) over OAuth — its own host, not a router path.
• Router stitches the six under one hostname.
• CLI (apps/cli) is livediagram, the command line agents and scripts read, lint and change documents with, published on npm as @livediagram/cli. It also links a repository to its diagrams and opens a document inside a developer tool (CLI, Repositories, Workbench embeds).

The whole stack runs on Cloudflare Workers (Static Assets for the Next.js apps). There's no Node-hosted backend, no SSR, no Next.js API routes.

The rules that keep the repo honest

• Specs first: every product decision lives in docs/specs/. Write or update the spec before the code. See docs/development/contributing.md.
• Static-only frontends: Next.js output: 'export'. Server logic goes in the api worker, never in Next.js.
• Reuse over duplication: shared code lives in packages/, never copied across apps.
• No secrets in source: the repo is public. Env vars, wrangler secret put, GitHub Actions secrets only. See docs/specs/002-project-scope/secrets-policy.md.

Security

Found a vulnerability? Please report it privately through GitHub's advisory form, never in a public issue. See SECURITY.md and the full policy.

License

MIT. Anyone can self-host. A free hosted version runs alongside at livediagram.app; there's no paid tier and no plan to introduce one (docs/specs/002-project-scope/open-source-and-business-model.md). Its SaaS integrations are all optional — Clerk (auth), Resend (transactional email), and OpenAI (the AI assistant), each gated on its own key — and the editor runs fully without any of them.

Icon artwork includes Lucide (ISC) and Feather (MIT); see THIRD_PARTY_NOTICES.md. Every third-party work the deployed apps ship is credited, with its licence and notices, on the generated /licences page (Third-party licences).