Starlark is one of those things that reminds you about how trends in computing are totally circular. In the early days, people strung together configuration through imperative shell scripts and Lua scripts and the like. Then there was this massive push toward declarative configuration DSLs and configuration-as-code and we got Terraform and a whole mess of YAML in every "cloud-native" open source project. And now we're shifting back to writing configuration imperatively as regular programs with Starlark and similar languages. No doubt another 5 years from now we'll just switch everything back to declarative once programmers get bored of the current trend.