rules_ruby

Formerly canonical rules for ruby, that are about 2-3 years behind current Bazel. If they work for you great, but if not — please try the new rules ruby by Alex Radionov: https://github.com/bazel-contrib/rules_ruby. Maintained by bazelruby on GitHub, where it has earned 99 stars from the community.

It's actively developed around bazel, bazel-examples, build-systems, and is a solid reference for anyone building with these tools.