Gitlab feels also a bit weird to me, though.

The git part is perfectly fine, but at my job we're trying to get our cloud tool landscape to work with gitlab CI and it's really a struggle.

Something as simple as packaging the same artifact in two different ways or running tests in docker images before pushing them is really hard. Gitlab seems to insist on having a single commit as its entire context and communication between stages (especially on different runners) is almost laughably limited.

Jenkins on the other hand has at least the option to have a shared workspace. Yes, this has its downsides, but at least I have the option. Gitlab forces you to use outside tools in very involved ways or follow exactly their own, highly opinionated approach.