Bazel 8 and MPI

[lucasgrjn]

Hello everyone!

I'm new to Bazel and would like to use it for its cross-compilation and dependency management features.

My current goal is to build the Palace project, which is a C++ application that depends on MPI for parallel computing. For that, I would need to configure Bazel with OpenMPI (including its installation).

My questions are:

1. What is the recommended way to use Bazel with MPI? (Using a system-installed could be easier, but it goes against the principles of reproducibility… So ideally, I would like to build it from source)
2. I did not find any existing Bazel rulesets (like a rules_mpi)… Do you know any projects relying on it I could take a look at?
3. Any other advice?

Thanks for your help and your insights!
Lucas