Stu, if you are new to F/OSS and not yet rooted in a particular project, look out for those that have decent continuous integration toolchains. Look for projects whose GitHub master branches are protected, and where no patches land without a Travis or Jenkins build. Look for those that have good testing coverage and where developers evidently make an effort to have a unit and functional test for everything.

This is not just a technical issue. It doesn’t just make contributing easier for you without the fear of breaking something, although that is, admittedly, a nice side effect. It also tells you that the existing developers care about code quality, and that they prefer to trust an automated quality toolchain more than politics, when it comes to the decision of what patches go in and what don’t.