jupyterlab-myst-syntax

MyST Markdown syntax highlighting in JupyterLab 4, in notebook Markdown cells and in .md file editors.

It highlights the MyST syntax in the CodeMirror column of the syntax package’s table, on top of Lab’s own Markdown highlighting. It only highlights. MyST Author’s Lab extension handles preview and cross-references.

Install¶

It isn’t published yet, so build it from source as below. Once it is:

pip install jupyterlab-myst-syntax

How it works¶

Lab’s notebook Markdown cells and .md files both use its ipythongfm language. Lab registers that language itself, and the language registry has no supported way to replace it. Editors load the language from the registration’s support field when they open. So the extension rebuilds Lab’s Markdown parser with myst-syntax/codemirror added, and sets support to that.

Build¶

You need Node 24 and a python with JupyterLab installed, because build.mjs reads Lab’s list of shared packages from it. From the repository root:

npm install
npm run build -w packages/jupyterlab    # writes jupyterlab_myst_syntax/labextension

To try it in your own Lab without a wheel:

mkdir -p "$(jupyter --data-dir)/labextensions"
ln -sfn "$PWD/packages/jupyterlab/jupyterlab_myst_syntax/labextension" "$(jupyter --data-dir)/labextensions/jupyterlab-myst-syntax"

Rebuild and reload the page after changes.

Releasing is described in the repository README.