HgInit is maintained as Jekyll website, using minor Jekyll features for templating, and GitHub Pages for publication.
For minor contributions, you can use the GitHub user-interface: https://docs.github.com/en/repositories/working-with-files/managing-files/editing-files
To get started with local development, Please install Jekyll. See detailed guides for your operating system.
To test your changes locally, you can run Jekyll:
jekyll serve -w --incremental
then open http://localhost:4000 in your browser.
You can use GitHub Codespaces to work on the repository remotely. Just run jekyll serve -w --incremental in the terminal window, and forward port 4000 to view your changes.