plain files · live collaboration · zero migration

Your folder,
now multiplayer.

CollabMD serves your Obsidian vault, docs repo, or any folder of Markdown and diagrams as a realtime collaborative web app. No content migration — your filesystem stays the source of truth.

Open the guided demo Star on GitHub

No signup. Skip the name prompt to enter as a guest.

CollabMD live demo workspace: markdown editor with embedded Mermaid, PlantUML, Excalidraw, and draw.io files, rendered diagram preview, and six collaborators online.
Captured from the live public demo — six collaborators online, no signup required.
~/my-vault — zsh
$npx collabmd@latest ~/my-vault --no-tunnel
CollabMD v0.1.43
Vault:/Users/you/my-vault
Local:http://localhost:1234
Tunnel:disabled
● Ready for collaboration. Press Ctrl+C to stop.
$
  • MIT licensed
  • Yjs CRDTs
  • Filesystem = source of truth
  • Node 24 · Docker · Homebrew

~/features

Built like a dev tool,
not a document silo.

~/local-files-first

No migration. Files stay files.

Point CollabMD at an existing Obsidian vault, docs repo, or plain folder. It reads and writes supported files in place instead of importing them into a proprietary content store. Edits made in Obsidian, your editor, or by git pull reconcile straight back into open sessions and the file explorer.

  • Markdown and diagram sources remain ordinary files on disk
  • Opening a file does not rewrite its source content
  • Ignores .obsidian, .git, node_modules

~/realtime-collaboration

Everyone on the same line, live.

Yjs merges concurrent edits without locks or conflict dialogs. See who's online, follow a collaborator's cursor across files, and hash things out in room chat without leaving the workspace.

  • Presence, follow mode, and room chat built in
  • Edits stream over WebSocket, persist to disk continuously
  • Works over a LAN or a shared tunnel link

~/source-anchored-comments

Feedback pinned to the exact words.

Comment on a line or a selected phrase. Threads sit beside the source with inline markers and preview bubbles — reviewers see the sentence, not a screenshot of it. Resolve when the work lands.

  • Inline editor markers and rendered preview bubbles
  • Workspace-wide comment overview grouped by file
  • Markdown, Mermaid, and PlantUML sources

~/diagrams

Diagrams are first-class files.

Mermaid, PlantUML, Excalidraw, and draw.io render inline in previews and open as standalone files — so they stay versionable, diffable, and shareable like everything else in the vault.

  • Fenced blocks and standalone .mmd / .puml side-by-side editing
  • Shared Excalidraw canvas; hosted or self-hosted diagrams.net editor
  • Configurable PlantUML renderer — public by default, self-hostable

[[wiki-links]]

Navigate the whole vault

Wiki-links, backlinks, outline, and a quick switcher keep every note close.

rg --files

Search every file

Ripgrep-backed results stay fast and arrive grouped by file.

git push

Review, commit, publish

Inspect diffs and publish from the app while history stays in your repo.

~/see-it-in-action

Don't take our word for it.
Take the wheel.

This is a recording of the guided README at demo.collabmd.app — a real shared vault open to anyone. Type something and watch it render.

demo.collabmd.app Start in the guided README. No signup; join as a guest.

~/how-it-works

Three steps.
The middle one is a browser.

  1. 1

    Point at a folder

    Any directory of Markdown works — an Obsidian vault, a docs repo, a pile of notes.

    npx collabmd@latest ~/my-vault
  2. 2

    Open the browser

    Explorer, editor, live preview, comments, and chat are waiting at localhost:1234.

    open http://localhost:1234
  3. 3

    Share the link

    Add a password and let the quick tunnel print a URL your collaborators can open.

    collabmd ~/my-vault --auth password

~/install

Choose how to run it.

macOS, Linux, or Windows via WSL2. Requires Node.js 24 for the npx path; ripgrep powers global search.

npx collabmd@latest ~/my-vault --no-tunnel

Then open http://localhost:1234. No global install required.

--auth

Control access

Use a LAN, shared password, or Google OIDC with per-user identity.

docker run

Deploy your way

Run the published image, Compose stack, or Helm chart.

cloudflared

Share a link

An optional quick tunnel exposes HTTP and WebSocket together.

Stop migrating your docs.
Start collaborating on them.

Open the guided demo andes90/collabmd