You'll need Node.js to run the site. Check the version in `package.json`. To install Node.js, [download the "LTS" installer from nodejs.org](https://nodejs.org). If you're using [`nodenv`](https://github.com/nodenv/nodenv), read the [`nodenv` docs](https://github.com/nodenv/nodenv#readme) for instructions on switching Node.js versions.
As an alternative, you can simply use [GitHub Codespaces](https://docs.github.com/en/codespaces/overview). For more information about using a codespace for working on GitHub documentation, see "[Working in a codespace](https://github.com/github/docs/blob/main/contributing/codespace.md)."
The [`script/bookmarklets`](../script/bookmarklets) directory contains some browser shortcuts that can help with reviewing GitHub documentation. See [`script/bookmarklets/README.md`](../script/bookmarklets/README.md) for details.
By default the local server won't run with all supported languages enabled. If you need to run the server with a particular language, you can temporarily edit the `start` script in `package.json` and update the `ENABLED_LANGUAGES` variable. For example, to enable Japanese and Portuguese, you can set it to `ENABLED_LANGUAGES='en,ja,pt'` and then you need to restart the server for the change to take effect.
This site was originally a Ruby on Rails web application. Some time later it was converted into a static site powered by [Jekyll](https://jekyllrb.com/). A few years after that it was migrated to [Nanoc](https://nanoc.app/), another Ruby static site generator.
Today it's a dynamic Node.js webserver powered by Express, using [middleware](../middleware/README.md) to support proper HTTP redirects, language header detection, and dynamic content generation to support the various flavors of GitHub's product documentation, like GitHub.com and GitHub Enterprise Server.
The tooling for this site has changed over the years, but many of the tried-and-true authoring conventions of the original Jekyll site have been preserved:
- Content is written in Markdown files, which live in the `content` directory.
- Content can use the [Liquid templating language](liquid-helpers.md).
- Files in the `data` directory are available to templates via the `{% data %}` tag.
- Markdown files can contain [frontmatter](https://jekyllrb.com/docs/front-matter).
- The [`redirect_from`](https://github.com/jekyll/jekyll-redirect-from) Jekyll plugin behavior is supported.
