Have you looked into Bazel? https://bazel.build/start/cpp https://bazel.build/start/cpp It's not always easy to use, but the focus on reproducible builds and c

Have you looked into Bazel? https://bazel.build/start/cpp https://bazel.build/start/cpp It's not always easy to use, but the focus on reproducible builds and caching is really nice. Edit: I guess it doesn't fetch a specific compiler for you by default, but you could probably ship your toolchain somewhere and pin it in your WORKSPACE file.