Azure Pipelines, our hosted CI/CD solution, has been offering developers the ability to build and test applications using Microsoft-hosted macOS and Xcode agents, including apps for iOS and watchOS.

Earlier this year, we were excited to share with you that the Hosted macOS agents were going to be upgraded to OS X 10.14 (Mojave). At the time of that announcement we said that we were plannig to drop support for High Sierra and Xcode versions below 9.4.1. Having spoken with a number of teams about their customers adoption of the latest macOS updates, we have decided to keep the High Sierra image available and maintained. This not only helps teams who need older versions of Xcode for their builds, but it also allows you to build with the latest bits on Mojave and then run automated tests with High Sierra as well.

Picking the right macOS Version

Based on your build needs, you can choose to use High Sierra or Mojave build agents. If your build requires an Xcode version prior to 9.4.1, choose High Sierra. On the other hand, builds using Xcode 10.2 and higher will only build on Mojave agents. You can always see the full list of tools installed in each image in our GitHub repository. After identifying which macOS version is right for you, you can select the version via the classic UI editor or by specifying the image in your YAML file.

If you had previously selected Hosted macOS in the Agent Pool dropdown in the UI editor, your builds are already running on Mojave. To switch back to High Sierra or target High Sierra for new pipelines, select Hosted macOS High Sierra in the Agent Pool dropdown.

For pipelines using YAML, simply specify the macOS version using the snippets below:

    jobs:
    - job: macOS
      pool:
        vmImage: 'macOS-10.14'
      steps:
      - script: echo hello from macOS Mojave
    - job: macOS
      pool:
        vmImage: 'macOS-10.13'
      steps:
      - script: echo hello from macOS High Sierra
    - job: macOS
      pool:
        vmImage: 'macOS-latest'
      steps:
      - script: echo hello from the latest version of macOS available

For additional information on our Hosted Agents, please refer to our documentation.

Next Steps for Hosted macOS Agents

We are looking forward to announcements to come from Apple’s Worldwide Developers Conference in June. We will continue to provide support for the latest macOS and Xcode versions to enable you to develop great experiences targeted to Apple’s ecosystem, including macOS, iOS, and watchOS. In addition to keeping our macOS build agents up-to-date, we will continue to look into and update other tools that are added to the agents. Open up an issue in our GitHub repositoryfor any tools you would like to see added or any issues you run into.

Reach out to us @AzureDevOps, or directly to me @nilli_minaj, for any questions or feedback. Happy building!