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GitHub Actions macOS: Changes in 2025

July 11, 2025

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by Macfleet Team

GitHub is implementing significant changes to its macOS hosted runners infrastructure starting August 2025. These updates will affect how developers build, test, and deploy their applications using GitHub Actions. Here's everything you need to know about these changes and how to prepare your workflows.

Major Changes Coming to macOS Runners

macos-latest Migration to macOS 15

Starting August 4, 2025, GitHub will begin migrating the macos-latest label to point to macOS 15 runner images. This migration affects:

• macos-latest
• macos-latest-large
• macos-latest-xlarge

Timeline:

• Migration begins: August 4, 2025
• Migration completes: September 1, 2025
• Once migrated, workflows will no longer run on macOS 14

Xcode Support Policy Update

Beginning August 11, 2025, GitHub is changing its Xcode support policy:

• Continued support: All bare bones Xcode versions will remain available
• Limited simulators: Maximum of 3 runtimes (simulators) will be maintained
• Beta support: Beta runtimes will be available on a best-effort basis only

This change aims to optimize image performance and reduce maintenance overhead.

macOS 13 Retirement

Following GitHub's N-1 OS support policy, macOS 13 hosted runners are being phased out:

• Retirement begins: September 1, 2025
• Full retirement: November 14, 2025
• Recommendation: Migrate to macos-14 or macos-15

Impact on Your CI/CD Workflows

These changes may affect your workflows in several ways:

Immediate Actions Required

1. Review your workflows that use macos-latest labels
2. Test compatibility with macOS 15 for your applications
3. Update dependencies that may not be compatible with newer macOS versions
4. Check Xcode version requirements for your projects

Potential Issues

• Breaking changes: Some tools may not work on macOS 15
• Xcode compatibility: Limited simulator availability may affect testing
• Performance changes: Different behavior on newer macOS versions
• Third-party dependencies: May need updates for macOS 15 compatibility

Best Practices for the Transition

For GitHub Actions Users

1. Pin specific versions instead of using macos-latest:

   jobs:
     build:
       runs-on: macos-14  # Instead of macos-latest

2. Test early: Start testing on macOS 15 before the migration

3. Monitor workflows: Watch for failures during the transition period

For Xcode Projects

1. Audit simulator dependencies: Ensure your tests work with limited simulators
2. Update CI scripts: Adapt to new Xcode support policies
3. Test beta compatibility: Don't rely on beta Xcode versions in production

Timeline Summary

Date	Change
August 4, 2025	macos-latest migration begins
August 11, 2025	New Xcode support policy takes effect
September 1, 2025	macos-latest migration completes, macOS 13 retirement begins
November 14, 2025	macOS 13 fully retired

Get Started

Ready to ensure your macOS builds remain stable through GitHub's changes? Sign up for Macfleet today and take control of your CI/CD infrastructure.