macOS 27 Golden Gate RC with Xcode 27.2 Now Available

macOS 27 Golden Gate is in Release Candidate, and it is on GetMac today under the new getmac-golden-gate-rc label: macOS 27.2 (26B123) with Xcode 27.2 (27B52). It is the first GetMac image on the macOS 27 generation, so you can find out what Golden Gate does to your build now rather than after it ships.

What's New

• Xcode 27.2 — Build 27B52, selected by default. Xcode 27.1, 27.0, 26.6 and 16.4 are installed alongside it, so one label covers five toolchains.
• The Metal toolchain is pre-installed for every Xcode 26+ version — see below. This is the change most likely to show up in your build times.
• 27.2 simulator runtimes across all four platforms — iOS 27.2, tvOS 27.2, watchOS 27.2 and visionOS 27.2, alongside the 27.0, 26.5 and legacy 18.x/11.x/2.x runtimes.
• Java 27.0.1 — Up from 26.0.2.1 on the RC image.
• Rust 1.99.1 and Go 1.27.3 — Up from 1.98.1 and 1.27.1.
• Updated CLIs — AWS CLI 2.39.6, Google Cloud SDK 592.0.0, and GitHub CLI 2.103.3.
• Mobile build tools — Fastlane 2.241.2 (from 2.240.1), CocoaPods 1.17.0.
• Node.js packages — TypeScript 7.0.2, pnpm 12.18.0, npm 11.20.0, and eslint 10.14.0.
• Ruby 4.0.9 under rbenv, with bundler 4.0.20.
• Android SDK — Emulator 37.2.13, Platform-Tools 37.0.1, Build-Tools 34 & 35, NDK 27, and SDK Manager 12.0.
• Google Chrome 157.0.8103.39 with a matching ChromeDriver 157.0.8103.38, at /usr/local/bin/chromedriver with CHROMEWEBDRIVER set to its directory.

The Metal Toolchain Is Already Installed

From Xcode 26, Apple stopped bundling the Metal compiler with Xcode and ships it as a separately downloadable component. On a stock runner that means the first xcrun metal in your build spends roughly 839 MB and several minutes fetching the toolchain from Apple before it compiles a single shader. Because the download comes from Apple's servers rather than ours, no build cache — ours or anyone's — can serve it for you.

On this image the toolchain is already mounted for every Xcode 26+ version, so a shader build starts compiling immediately:

If your project builds .metal files, or depends on anything that does — SceneKit, RealityKit, MetalFX, most game engines, a surprising number of image-processing packages — this is the difference between a job that compiles shaders and a job that downloads a compiler first.

Five Xcode Versions, One Label

Xcode 27.2 is selected by default. To build with any of the others, point DEVELOPER_DIR at it:

- name: Build with Xcode 27.1
  env:
    DEVELOPER_DIR: /Applications/Xcode_27.1.app/Contents/Developer
  run: xcodebuild -version

Short names resolve to the installed build, so /Applications/Xcode_27.1.app works without knowing the patch version.

Check Before You Switch

• This is a Release Candidate. macOS 27.2 and Xcode 27.2 are both pre-release generations. Run your full build and test suite here before you rely on it, and keep release builds on a stable label.
• Two iOS 27.2 simulator runtimes are installed. One is the general runtime; the other is a device-specific variant that Apple ships for a single hardware model and that rejects every other device. If a simctl create or an xcodebuild -destination starts answering "Incompatible device", you have landed on the device-specific one — select the runtime explicitly rather than taking the newest. The same applied to iOS 27.1 and the iPhone Duo.
• Docker and Colima are not installed, as on our other images.
• libffi and curl are no longer installed through Homebrew on this image. The system curl is still at /usr/bin/curl.
• Major version bumps. Java 27, Rust 1.99 and Ruby 4.0 are all new generations relative to our stable image.

Our Other Labels Move on 19 November

Separately from this release, on Thursday 19 November at 12:00 UTC three of our labels start pointing at a newer image. Nothing in your workflow file changes — each label keeps its name, and no image is rebuilt, because every one of these is already running on our fleet:

If you need to stay where getmac is today, move to getmac-tahoe-legacy — from the 19th that label is Tahoe 26.5.2 with Xcode 26.6, exactly where getmac is now. If you are already on getmac-tahoe-rc, nothing changes for you: getmac is catching up to the image you are on.

macOS Tahoe 26.3.2 with Xcode 26.4 is retired on the 19th. getmac-tahoe-legacy is the only label that still reaches it, and once that label moves to 26.5.2, nothing points at it. If you are pinned to Xcode 26.4 for a reason, tell us before then and we will work out where to put you.

GitHub Actions Integration

Use the following labels in your runs-on field:

• getmac, getmac-latest, or getmac-tahoe — macOS Tahoe 26.5.2 with Xcode 26.6 (current stable)
• getmac-golden-gate-rc — macOS 27.2 Golden Gate with Xcode 27.2 (Release Candidate)
• getmac-tahoe-rc — macOS Tahoe 26.6.2 with Xcode 27.0 and 27.1
• getmac-tahoe-legacy — macOS Tahoe 26.3.2 with Xcode 26.4

- runs-on: getmac-tahoe
+ runs-on: getmac-golden-gate-rc

To validate against Golden Gate without giving up your stable builds, run both side by side with a matrix:

jobs:
  build:
    strategy:
      matrix:
        runner: [getmac, getmac-golden-gate-rc]
    runs-on: ${{ matrix.runner }}

For the full list of available labels, see our Workflow Labels documentation. For a complete breakdown of pre-installed tools, simulators, and SDKs, see the Installed Tools & Libraries page.

Get Started

The image is live now. Point a job at getmac-golden-gate-rc to build and test against macOS 27 and Xcode 27.2.

As always, we'd love to hear your feedback — join our Discord community to share thoughts or request new tools.

— The GetMac Team