No, it's actually the opposite - it has very rigid build rules with rigid inputs and outputs so the toolchain can reason about dependencies and it doesn't reall

No, it's actually the opposite - it has very rigid build rules with rigid inputs and outputs so the toolchain can reason about dependencies and it doesn't really allow adding arbitrary execution in the BUILD files to prevent code messing up caching and remote builds. It was build to solve a problem of building software at scale across multiple languages, platforms in a single monorepo. And it's great at that. It becomes limiting as your use-case steps away from this "monorepo, across languages" approach.