Guides

Short, checkable answers to the questions teams hit when they run macOS CI on GitHub Actions. Written from what we see running open-source iOS and macOS projects on Manzanita; every number links to where it can be verified.

• Manzanita vs GitHub-hosted macOS runners

  Hardware, Xcode pinning, queueing and per-minute vs flat-rate pricing, side by side.

• A Cirrus Runners alternative for macOS

  Label mapping, pricing and hardware next to Cirrus Runners, and a migration order that works.

• Which Xcode does macos-latest run?

  The alias moves under you. How to see what you are on and pin it on either kind of runner.

• Why macOS jobs queue on GitHub Actions

  Three different waits hide behind “Queued”. How to tell them apart and which ones you can fix.

• Running Xcode 26 on GitHub Actions

  A low-risk order for adding an Xcode 26 lane, reading the first failures, and flipping the default.

• iOS simulator tests on GitHub Actions

  Cold boots, destination naming, older runtimes, and the GUI session settings UI tests need.

• Caching SwiftPM and DerivedData on macOS runners

  A working actions/cache block, what to key on, and what not to cache on ephemeral runners.

• Runner image changelog

  Every image promotion with digest-pinned manifests.