This is a great project - is the goal to be more like Gitlab, i.e. no plugins/marketplace or like Jenkins and GitHub Actions?
I am looking forward to a mix of both - I am hoping to add a concept called "operator" which would be a go-plugin [1], just like terraform providers, but build backends. So, someone would be able to, say, write a Slack plugin (in Go, or anything over RPC) which sends a message once a build is complete - like Jenkins/GitHub actions, or just scripts that we can reuse like GitLab CI through `modules`.
Perhaps a new registry where we can push custom modules and providers (operators in this case), I'm curious to know about if we have any existing implementations we could reuse for the registry.