aarch64 and arm64 builds

Changed on 2024-03-04: Added this section as initial linux-aarch64 builds are starting

Changed on 2024-04-04: Information about osx-arm64 builds

Changed on 2026-08-02: Move linux-aarch64 builds to the same GitHub Actions matrices as linux-64 and enable multi-architecture container publication.

Bioconda supports opt-in linux-aarch64 and osx-arm64 builds (see Understanding platform nomenclature). Linux builds run in multi-architecture GitHub Actions matrices. The scarce macOS ARM runners used for PR and master builds remain on CircleCI, while bulk and nightly macOS ARM builds run on GitHub Actions.

This is being initially approached as an opt-in process as we make sure all the moving parts are working correctly. A recipe can be flagged for building on linux-aarch64 and/or osx-arm64 by adding the following to the meta.yaml file:

extra:
  additional-platforms:
    - linux-aarch64
    - osx-arm64

The CircleCI macOS ARM jobs stop before environment setup unless at least one recipe in the commit range includes osx-arm64 as an additional platform. Linux ARM jobs can start for every workflow invocation; bioconda-utils selects only recipes that opt in to linux-aarch64.

For recipes that produce mulled containers, Linux builds publish architecture images and then reconcile them into a multi-architecture manifest. The workflow uses conda package subdirectories such as linux-aarch64 as its public platform values; bioconda-utils derives OCI values such as linux/arm64 internally.