@jas At the moment you need to manually connect worker nodes to controller nodes by generating and sharing tokens. Other than that it seems as a perfectly normal kubernetes installation.
Not sure what do you mean by gitlab connection to k8s cluster.
There is a partial and very bare-bone implementation of cloud init we use:
https://git.sr.ht/~abcdw/rde/tree/11fb136c/src/rde/system/services/cloud-init.scm#L50
Written by David Dashyan and @krevedkokun.