[sofixa]

All the VCS providers come with an included CI, which usually blows Jenkins out of the water. Even if I'm not fond of GitHub Actions' syntax, it's still better than Jenkins. The native integrations, if nothing else with MR/PRs and identity and access management are great.

So in a way, an external CI system is a very niche thing. If for some reason that is still needed, I've heard good things about Concourse CI. The last separate CI I've used was Drone CI for fun, but AFAIK it's no longer open source after they got acquired by Harness.