I have recently started to get involved helping out with the rust-bindgen program for generating rust bindings to C++ programs. It really is amazing the amount of work they put into creating issues for small things for new people to fix and mentoring them through the issue. I don't know of any programming languages that put this much work into helping new people get started. It really was a great experience to be have bite sized things to fix that actually feel like contributing to a project without worry that you are taking on more than you can chew.