Ask HN: What self-hostable CI system are you using?

I am currently using self-hosted Jenkins for my solo projects. I am considering switching to something new. Anything you can recommend? The only real requirement is that it needs to be easy to self host, not be too complicated (solo dev so I want most of my focus to go to developing not figuring out the CI) and be resource efficient (I only have 1 server).

I am fairly happy with Jenkins but mostly because I am familiar with it. Only real downside is the resource usage when idle. And some plugins are not really maintained anymore.