This is a simple collaborative Markdown editor built in React, with inline format preview and inline commenting.
It's built on automerge and automerge-repo for CRDT-based storage and sync. It uses Codemirror for markdown editing UI, and automerge-codemirror to connect to Codemirror.

This app is primarily intended for internal use at Ink & Switch for editing essays, so there are some features that are specialized towards that use case. We don't plan to develop it into a general-purpose editor that anyone can use for anything. But of course, it can edit any Markdown document too. If you want to actually use this editor in earnest, you might want to fork it to build your own ideas.
Hopefully the code serves as a useful sample for building apps based on automerge-repo, automerge-codemirror, and React.
- If you visit the root domain the app will make a new doc. Or you can hit the New button.
- Once you have a doc, the URL will update with a doc ID. If you share that URL to another browser/device, it should sync live. Hold on to the URL if you want to come back to that doc!
- Edit Markdown with inline format preview
- Write inline comments + replies
- Live sync through Automerge
- Save out .md file with a Download button
- Typeset similarly to Ink & Switch essays
yarn
yarn dev
when the vendored version of automerge or automerge-repo are updated you need to run:
yarn clean cache
rm yarn.lock
yarn
This is necessary because we want to install automerge / automerge-repo on a specific branch without having to bump the version every time. Unfortunately yarn caches tarballs based on the version number in the package.json and the yarn file has a integretiy checksum that prohibits installing a different version if the version number hasn't changed.
This app is designed for normal webapp deployment as well as experimental deployment to an internal I&S platform. The code is almost entirely shared but there are two entry points:
src/main.tsx
is the normal app entry pointsrc/index.ts
is an experimental entry point which just exports some functions to a host environment
We are using vendored version for automerge and automerge-repo so we can use experimental features. These are checked into the repo as tarballs in the folder vendor/tarballs
. Usually you don't have to worry about this.
First you need to clone automerge and automerge-repo. The following command will clone both into the vendor/repos
folder
yarn run vendor:init
Checkout the version you want in vendor/repos/automerge-repo
. Then you can run:
yarn run vendor:build-automerge-repo
If you want to vendor in a different version of automerge you need to make sure that you have installed the necessary dependencies. Instructions for that are in repo of automerge (https://github.com/automerge/automerge).
Once you have done that you can checkout the version you want in vendor/repos/automerge
. Then you can run:
yarn run vendor:build-automerge