This is the very core of what our community is about. You don't need to know the ins and outs of a project to collaborate, you can make your own, somewhat independent improvements or you can join full-fledged brainstorm and planning meetings and involve yourself in planning the next milestone. Or start your own project and ask people to help out, start learning a language and ask seasoned veterans, or just play your way. In fact, this very website you are on happens to be a collaborative effort.

It is necessary to say though that the entire purpose of a community like this is to engage in each others' projects and collaborate on them, with the Gitlab instance serving as the center piece making it possible.