The seL4.systems website is built with the static site generator Jekyll, which uses the Liquid templating engine.
We recommend using rbenv to install the correct Ruby version.
On Mac, using homebrew:
brew install ruby-build rbenv
On apt-based Linux distributions (e.g. Ubuntu, Debian):
apt install rbenv
# follow the instructions this command shows, and start a new shell afterwards
rbenv init
# in the docs directory (root of this repo):
rbenv install
After these, you should be able to forget about rbenv
, the Makefile
will now
see the correct Ruby version.
The site uses Tailwind CSS, which requires node
. Any node
version >= 20
should work, the automated build is using the latest patch release of version
22.
You can install node
on via brew install node
or apt install node
depending on your OS. If your OS comes with a too-old version of node
pre-installed, we recommend using the node version manager
nvm. Its README has a one-touch install script.
Once nvm
is installed, you can get the correct node
version by running nvm install
in the root directory of this repository.
To manually run the html5validator
script via make validate
, you need to
install
pip install --user html5validator
The validator also needs a working Java runtime installation, which you can get from https://java.com or via your package manager.
Running make build
will generate the pages and put them into the
_site/
directory. To preview the website locally, run
make serve
for the production build and make debug
for the development build. See make help
for all options.
There are two variants of the website to build. When running on seL4 the site includes an additional footer with a link to pages describing the setup. To build this variant, use
make on_seL4
The site will be generated into _site_on_seL4/
.
Contributions are welcome — if you find anything out of date, any typos or inaccuracies, please raise a pull request on this repository.
For the preview functionality on pull requests to work, all links to internal
pages and images need to be relative to the file they are made from. That
means, please do not use links that start with a /
such as
/Foundation/page.html
even though Jekyll encourages that.
There are two ways to use relative links: either directly use the relative path
(usually nicer), or use the relative_url
function in Jekyll/Liquid.
Examples:
<a href="../Foundation/a-page.html">
<img src="../images/something.jpg">
With relative_url
:
<a href="{{ '/Foundation/a-page.html' | relative_url }}">
Note: relative_url
only produces a site-relative URL not a path-relative URL,
but Jekyll has enough setup to prepend the correct prefix for the GitHub
previews to work, so it is fine to use.
link
tags in the front matter of pages are automatically used with
relative_url
, so it is fine to use absolute links there.
News items can potentially get included from multiple pages. Always use
relative_url
in those.
Files in this repository (with a few exceptions) are released under standard open source licences, identified by SPDX Licence tags. See individual file headers for details.
As a general rule, new code files should be under BSD-2-Clause, and documents under the [Creative Commons Licence CC-BY-SA 4.0 International licence in this repository.
Some files contain representations of trademarks. Irrespective of any licence markings, logos and trademarks in this repository are owned by their respective owners. No licenses or other rights in or to such logos and/or trademarks are granted. The Trademark guidelines for the seL4 Foundation can be found at https://sel4.systems/Legal/trademark.html
Permission to use pictures of people have been granted for display on the seL4.systems website only. Please do not use them for any other purpose.