Starlark (originally Skylark) is the configuration/extension language of Google's build tool Bazel.

It's a bespoke Python subset... functions but no recursion, dicts but no sets, etc.

It's also been adopted by the latest version of Buck (Meta's Bazel analog).

I use it daily.

It's an option for lightweight embeddable scripting language, with implementations in Java and Go. If you want Python familiarity, consider it as an option.