Add s390x (IBM Z) GitHub Actions runner to Erlang/OTP CI

Hi all,

I’d like to propose adding an s390x (IBM Z / LinuxONE) runner to the Erlang/OTP GitHub Actions CI pipeline.

Background

IBM has made hosted s390x GitHub Actions runners publicly available through their open-source sponsorship program. Details are here:

Why this matters

s390x is a big-endian 64-bit architecture. The existing CI covers little-endian platforms only (x86-64 and aarch64). Adding a big-endian runner closes a gap in architecture coverage.

What I’m asking

Would the team and community be open to:

  • Signing up for the IBM-hosted s390x runner via the onboarding guide above (it’s free for open-source projects).
  • Adding an s390x job to the existing GitHub Actions CI — either as a new workflow file or as an additional matrix entry in main.yaml.

I’m happy to help draft a PR once there’s interest. I can also help coordinate with IBM if there are questions about the runner program.

Thanks for considering this!