Hey There! I lead the Engineering Recruiting Team at GitLab. In addition to emilycook's reply, which I think summed up your question, I would say that we require aptitude in certain programming languages, which we measure with coding challenges, not years of experience. Many of us here are self-taught programmers (including the VPE of Engineering). You are welcome to apply and take the code challenge, or also start contributing to the open source project.