This weekend, the PieFed community is hosting a Hackathon.
Head over to the Issues list and lend a helping hand where you can!
Python, CSS, Translations, all kinds of things. I've submitted a few issues recently and found the code easy to comprehend.
https://tarte.nuage-libre.fr/c/fediverse/p/221411/hackathon-this-week-7-8-febuary
https://codeberg.org/rimu/pyfedi/issues?state=open