Pipelines: macOS 15 runners are now generally available

Starting today, macos-15 and macos-15-arm runner labels are generally available for every plan.

What changes

• The macos-latest label moves to macOS 15 over the next three weeks, in waves.

• Xcode 16.1 is the default toolchain; 15.4 stays installed for one more quarter.

• Arm runners boot roughly 40% faster than the Intel images in our tests.

jobs:
  build:
    runs-on: macos-15-arm
    steps:
      - uses: lattice/checkout@v4
      - run: xcodebuild -scheme App -destination 'platform=iOS Simulator,name=iPhone 16' test

If your workflow pins macos-13, nothing changes yet — we will post a separate notice before that image is retired.

Questions? Reply below and the runner team will pick them up.

Great news. Is there a timeline for larger arm runners (more than 6 cores)? Our test suite is CPU-bound.

Larger arm sizes are on the roadmap for early next quarter. We will announce them in this category first.

Confirmed our iOS build went from 14m to 8m on macos-15-arm. Thanks!