That's a shame, because Github actions is IME the worst productivity killer since you can't test locally- which makes iterating painfully long.
I haven't used GitLab CI runner too often, but the carrot of being able to use a runner on my local machine is extremely appealing.
Lots of room for innovation for sure. But if you think actions is bad try iterating on Windows slip streaming.
I haven't used personally but curious if it has some shortcomings they don't mention.
GA workflows are basically yaml lists of docker container names to run. I thought it would've been trivial to emulate. At least much easier than any other system.
Then to test locally you just do "make check".
The problem comes if you start using pre-made actions instead of simple commands.