Contributing to the SCION code base

Welcome to the SCION contribution guide! If you are interested in contributing to the project, this page will help you out on your journey to your first SCION commit.

Before starting out, just one thing: if you have any questions, you can always find us on our Slack workspace or on our Github project page. Do not hesitate to ask us anything, or feel free to just drop by and say “Hi”.


Note for Anapayans

This section contains general rules about how to contribute to the open-source SCION project. If you are an Anapaya employee, some additional rules may apply. Please see the internal Contribution Guide for more information.

What skills do you need to contribute?

SCION is a complex project, and uses a lot of different technologies. If you are unfamiliar with some of them, we have compiled a list containing some great resources to get you started.

Language Contribution area Tutorials
Go SCION Control-plane SCION Data-plane SCION Tools Resources for learning Go
Python Acceptance testing Helper scripts Coming soon
Starlark Bazel build/test system Coming soon

Contributing to the Python and Starlark code bases is a bit trickier, so if you’re just now starting out, we recommend going for Go first.

You might also see some Bash and Makefile code in the code base. While this code changes from time to time, we strongly discourage contributions to these areas. Code in these languages also has a high chance of getting deleted completely in a refactoring pass.

For version control, we use Git and GitHub. For more information about using Git (including links to resources to get you started if you’ve never used before), please visit How to Use Git and GitHub.

No matter what language you want to contribute to, one of the first steps to take is to set up a development environment. See Setting up the development environment for the needed steps. If you encounter issues, please visit Slack and ask for help.

Finding an issue to contribute to

We use GitHub labels to categorize issues in the SCION tracker. The two most interesting categories when searching for something to contribute to are:

  • Help wanted issues. These are issues that nobody is working on at the moment, and are up for grabs.
  • Good first issue issues. These are usually Help wanted uses that are somewhat simpler. These are a good place to start if you’ve never contributed to the project before.

Once you find something you like, post a comment on the issue announcing that you’re interested in working on it. This initial message signals to others that somebody is already working on it (and thus avoids duplicate work), and also is the first step in gathering more information about the issue from the SCION team.

From this point on, somebody from the SCION maintainers team will reach out to you and guide you for the rest of the process. If you have any questions, please remember to shoot us a question on our Slack.

Finally, make sure that the code you write adheres to the SCION project Language style guides.