I've been sitting on the fence wrt Terraform and other such tools for quite some time now. After being _forced_ to finally write massive k8s YAML files (and ansible YAML files) for a consulting gig, I've been wondering whether these tools should be developed as _libraries_, that you glue together using a full-fledged programming language, instead of shoe-horning a programming language in YAML.

For example, could the following be library functions that you could glue together in the programming language of your choice: (a) get current state of infra, (b) calculate diff between desired state and current state, (c) perform a single step (safely) that represents a granular change in infra, (d) perform a series of steps representing infra changes with safe rollback?

Does something like this already exist?