I'd say that non turing complete languages are a bad fit for pipelines. Even mildly complex pipeline will eventually have loops and conditionals.
Better python than some originally-a-config-YAML language turned into an imperative monstrosity with loops and conditionals bolted on.
I don't understand this move to define infra and CI imperatively, and tool vendors moving to support umptine languages for their users... Say what the world should look like, not how to get there?
It's really a blessing for something like CUE to come (I've had some exposure to gcl/bcl and if it wasn't for the internal diffing tool, I would've been lost - https://pure.tue.nl/ws/portalfiles/portal/46927079/638953-1.... )
I've even started prototyping something like bazel/gn but based on cue, but no time to finish it up.
You loop and branch in ansible/terraform
I hate that setup but also I have a hard time thinking of something else
Adding more YAML to be parsed by other YAML is just terrible at scale.
Ansible / Terraform are great when you're declarative, but once you start adding too much logic, things get hairy.
The problem is the attempt to make a distinction when there cannot be one.