Changelog

The Xcode 26.2.0 image is now available to be used in CircleCI pipelines on the M4 Pro resource classes.

Please see the full manifest for information about the software included with this image release.

Known issues:

• iOS 26 simulators sporadically freeze during boot and may fail to start. We recommend pre-booting simulators and, if they don’t start within 60 seconds, terminate them and restart them.
• Device IDs are inconsistently changing across VMs in Xcode 26. This is an OS-level issue that can affect builds relying on consistent device identifiers. We’ve opened a support ticket with Apple and encourage affected users to do the same to help prioritize a fix.

The Xcode 26.2 Beta 2 image is now available to be used in CircleCI pipelines on the M4 Pro resource classes.

Please see the full manifest for information about the software included with this image release.

Known issues:

• iOS 26 simulators sporadically freeze during boot and may fail to start. We recommend pre-booting simulators and, if they don’t start within 60 seconds, terminate them and restart them.
• Metal Toolchain is currently non-functional. A workaround is available by running the following commands before use:

    xcodebuild -downloadComponent metalToolchain -exportPath /tmp/MetalExport/
    sed -i '' -e 's/17C5038g/17A5241e/g' /tmp/MetalExport/MetalToolchain-17C5038g.exportedBundle/ExportMetadata.plist
    xcodebuild -importComponent metalToolchain -importPath /tmp/MetalExport/MetalToolchain-17C5038g.exportedBundle

• Device IDs are inconsistently changing across VMs in Xcode 26. This is an OS-level issue that can affect builds relying on consistent device identifiers. We’ve opened a support ticket with Apple and encourage affected users to do the same to help prioritize a fix.

The Xcode 26.1.1 image is now available to be used in CircleCI pipelines on the M4 Pro resource classes.

Please see the full manifest for information about the software included with this image release.

Known issues:

• OS 26 simulators sporadically freeze during boot and may fail to start. We recommend pre-booting simulators and, if they don’t start within 60 seconds, terminate them and restart them.
• Metal Toolchain is currently non-functional. A workaround is available by running the following commands before use:

    xcodebuild -downloadComponent metalToolchain -exportPath /tmp/MetalExport/
    sed -i '' -e 's/17A5295f/17A5241e/g' /tmp/MetalExport/MetalToolchain-17A5295f.exportedBundle/ExportMetadata.plist
    xcodebuild -importComponent metalToolchain -importPath /tmp/MetalExport/MetalToolchain-17A5295f.exportedBundle

• Device IDs are inconsistently changing across VMs in Xcode 26. This is an OS-level issue that can affect builds relying on consistent device identifiers. We’ve opened a support ticket with Apple and encourage affected users to do the same to help prioritize a fix.

The Xcode 26.1 image is now available to be used in CircleCI pipelines on the M4 Pro resource classes.

Please see the full manifest for information about the software included with this image release.

Known issues:

• OS 26 simulators sporadically freeze during boot and may fail to start. We recommend pre-booting simulators and, if they don’t start within 60 seconds, terminate them and restart them.
• Metal Toolchain is currently non-functional. A workaround is available by running the following commands before use:

    xcodebuild -downloadComponent metalToolchain -exportPath /tmp/MetalExport/
    sed -i '' -e 's/17A5295f/17A5241e/g' /tmp/MetalExport/MetalToolchain-17A5295f.exportedBundle/ExportMetadata.plist
    xcodebuild -importComponent metalToolchain -importPath /tmp/MetalExport/MetalToolchain-17A5295f.exportedBundle

• Device IDs are inconsistently changing across VMs in Xcode 26. This is an OS-level issue that can affect builds relying on consistent device identifiers. We’ve opened a support ticket with Apple and encourage affected users to do the same to help prioritize a fix.

The Xcode 26.1 RC (Release Candidate) image is now available to be used in CircleCI pipelines on the M4 Pro resource classes.

Please see the full manifest for information about the software included with this image release.

Known issues:

• OS 26 simulators sporadically freeze during boot and may fail to start. We recommend pre-booting simulators and, if they don’t start within 60 seconds, terminate them and restart them.
• Metal Toolchain is currently non-functional. A workaround is available by running the following commands before use:

    xcodebuild -downloadComponent metalToolchain -exportPath /tmp/MetalExport/
    sed -i '' -e 's/17A5295f/17A5241e/g' /tmp/MetalExport/MetalToolchain-17A5295f.exportedBundle/ExportMetadata.plist
    xcodebuild -importComponent metalToolchain -importPath /tmp/MetalExport/MetalToolchain-17A5295f.exportedBundle

• Device IDs are inconsistently changing across VMs in Xcode 26. This is an OS-level issue that can affect builds relying on consistent device identifiers. We’ve opened a support ticket with Apple and encourage affected users to do the same to help prioritize a fix.

The Xcode 26.1 Beta 3 image is now available to be used in CircleCI pipelines on the M4 Pro resource classes.

Please see the full manifest for information about the software included with this image release.

Known issues:

• OS 26 simulators sporadically freeze during boot and may fail to start. We recommend pre-booting simulators and, if they don’t start within 60 seconds, terminate them and restart them.
• Metal Toolchain is currently non-functional. A workaround is available by running the following commands before use:

    xcodebuild -downloadComponent metalToolchain -exportPath /tmp/MetalExport/
    sed -i '' -e 's/17A5295f/17A5241e/g' /tmp/MetalExport/MetalToolchain-17A5295f.exportedBundle/ExportMetadata.plist
    xcodebuild -importComponent metalToolchain -importPath /tmp/MetalExport/MetalToolchain-17A5295f.exportedBundle

• Device IDs are inconsistently changing across VMs in Xcode 26. This is an OS-level issue that can affect builds relying on consistent device identifiers. We’ve opened a support ticket with Apple and encourage affected users to do the same to help prioritize a fix.

The Xcode 26.1 Beta 2 image is now available to be used in CircleCI pipelines on the M4 Pro resource classes.

Please see the full manifest for information about the software included with this image release.

Known Issues:

• OS 26 simulators sporadically freeze during boot and may fail to start. We recommend pre-booting simulators and, if they don’t start within 60 seconds, terminate them and restart them.
• Metal Toolchain is currently non-functional. A workaround is available by running the following commands before use:

    xcodebuild -downloadComponent metalToolchain -exportPath /tmp/MetalExport/
    sed -i '' -e 's/17A5295f/17A5241e/g' /tmp/MetalExport/MetalToolchain-17A5295f.exportedBundle/ExportMetadata.plist
    xcodebuild -importComponent metalToolchain -importPath /tmp/MetalExport/MetalToolchain-17A5295f.exportedBundle

• Device IDs are inconsistently changing across VMs in Xcode 26. This is an OS-level issue that can affect builds relying on consistent device identifiers. We’ve opened a support ticket with Apple and encourage affected users to do the same to help prioritize a fix.

The Xcode 26.0.1 image is now available to be used in CircleCI pipelines on the M4 Pro resource classes.

Please see the full manifest for information about the software included with this image release.

Known Issues:

• iOS 26 simulators sporadically freeze during boot and may fail to start. We recommend pre-booting simulators and, if they don’t start within 60 seconds, terminate them and restart them.
• Metal Toolchain is currently non-functional. A workaround is available by running the following commands before use:

    xcodebuild -downloadComponent metalToolchain -exportPath /tmp/MetalExport/
    sed -i '' -e 's/17A5295f/17A5241e/g' /tmp/MetalExport/MetalToolchain-17A5295f.exportedBundle/ExportMetadata.plist
    xcodebuild -importComponent metalToolchain -importPath /tmp/MetalExport/MetalToolchain-17A5295f.exportedBundle
  

• Device IDs are inconsistently changing across VMs in Xcode 26. This is an OS-level issue that can affect builds relying on consistent device identifiers. We’ve opened a support ticket with Apple and encourage affected users to do the same to help prioritize a fix.

The Xcode 26.1 Beta 1 image is now available to be used in CircleCI pipelines on the M4 Pro resource classes.

Please see the full manifest for information about the software included with this image release.

Known Issues:

• iOS 26 simulators sporadically freeze during boot and may fail to start. We recommend pre-booting simulators and, if they don’t start within 60 seconds, terminate them and restart them.
• Metal Toolchain is currently non-functional. A workaround is available by running the following commands before use:

    xcodebuild -downloadComponent metalToolchain -exportPath /tmp/MetalExport/
    sed -i '' -e 's/17A5295f/17A5241e/g' /tmp/MetalExport/MetalToolchain-17A5295f.exportedBundle/ExportMetadata.plist
    xcodebuild -importComponent metalToolchain -importPath /tmp/MetalExport/MetalToolchain-17A5295f.exportedBundle
  

• Device IDs are inconsistently changing across VMs in Xcode 26. This is an OS-level issue that can affect builds relying on consistent device identifiers. We’ve opened a support ticket with Apple and encourage affected users to do the same to help prioritize a fix.

The Xcode 26.0 GA image is now available to be used in CircleCI pipelines on the M4 Pro resource classes.

Please see the full manifest for information about the software included with this image release.

Known Issues:

• iOS 26 simulators sporadically freeze during boot and may fail to start. We recommend pre-booting simulators and, if they don’t start within 60 seconds, terminate them and restart them.
• Metal Toolchain is currently non-functional. A workaround is available by running the following commands before use:

    xcodebuild -downloadComponent metalToolchain -exportPath /tmp/MetalExport/
    sed -i '' -e 's/17A5295f/17A5241e/g' /tmp/MetalExport/MetalToolchain-17A5295f.exportedBundle/ExportMetadata.plist
    xcodebuild -importComponent metalToolchain -importPath /tmp/MetalExport/MetalToolchain-17A5295f.exportedBundle
  

• Device IDs are inconsistently changing across VMs in Xcode 26. This is an OS-level issue that can affect builds relying on consistent device identifiers. We’ve opened a support ticket with Apple and encourage affected users to do the same to help prioritize a fix.
• See this community forum post for a workaround to a bug in the iOS 26 simulator device.

The Xcode 26.0 Beta 7 image is now available to be used in CircleCI pipelines on the M4 Pro resource classes.

Please see the full manifest for information about the software included with this image release.

Known Issues:

• iOS 26 simulators sporadically freeze during boot and may fail to start. We recommend pre-booting simulators and, if they don’t start within 60 seconds, terminate them and restart them.
• Metal Toolchain is currently non-functional. A workaround is available by running the following commands before use:

    xcodebuild -downloadComponent metalToolchain -exportPath /tmp/MetalExport/
    sed -i '' -e 's/17A5295f/17A5241e/g' /tmp/MetalExport/MetalToolchain-17A5295f.exportedBundle/ExportMetadata.plist
    xcodebuild -importComponent metalToolchain -importPath /tmp/MetalExport/MetalToolchain-17A5295f.exportedBundle
  

The Xcode 26.0 Beta 6 image is now available to be used in CircleCI pipelines on the M4 Pro resource classes.

Please see the full manifest for information about the software included with this image release.

Known Issues:

• iOS 26 simulators sporadically freeze during boot and may fail to start. We recommend pre-booting simulators and, if they don’t start within 60 seconds, terminate them and restart them.
• Metal Toolchain is currently non-functional. A workaround is available by running the following commands before use:

    xcodebuild -downloadComponent metalToolchain -exportPath /tmp/MetalExport/
    sed -i '' -e 's/17A5295f/17A5241e/g' /tmp/MetalExport/MetalToolchain-17A5295f.exportedBundle/ExportMetadata.plist
    xcodebuild -importComponent metalToolchain -importPath /tmp/MetalExport/MetalToolchain-17A5295f.exportedBundle
  

The Xcode 26.0 Beta 5 image is now available to be used in CircleCI pipelines on the M4 Pro resource classes.

Please see the full manifest for information about the software included with this image release.

Known Issues:

• iOS 26 simulators sporadically freeze during boot and may fail to start. We recommend pre-booting simulators and, if they don’t start within 60 seconds, terminate them and restart them.
• Metal Toolchain is currently non-functional. A workaround is available by running the following commands before use:

    xcodebuild -downloadComponent metalToolchain -exportPath /tmp/MetalExport/
    sed -i '' -e 's/17A5295f/17A5241e/g' /tmp/MetalExport/MetalToolchain-17A5295f.exportedBundle/ExportMetadata.plist
    xcodebuild -importComponent metalToolchain -importPath /tmp/MetalExport/MetalToolchain-17A5295f.exportedBundle
  

CircleCI server v4.0.0 is now generally available. The feature set for this release are equal to server v3.x. The installation and upgrade processes for v4.x have changed significantly.

Server v4.x offers greatly improved security handling, installation, and update processes. Server v4.x is installed using helm charts and images that can be pulled ahead of time to comply with your security processes. Installation processes can also use artifacts pulled from customer-managed registries. Server v4.x makes improved use of Kubernetes secrets and removes the requirement to grant permissions and network access to third-party tools.

Before upgrading

See the CircleCI server 4.x release notes for upgrade notes for this release.

What’s new in release 4.0.0

New features

• Two new Arm resource classes are now available xlarge and 2xlarge. For more information on using Arm, see the Arm docs.
• CircleCI server v4.x images and helm charts are available for licenced users.

Fixes

• Fixed a bug that was causing a huge quantity of error logs in the distributer-internal pod.
• Prometheus is no longer included by default in CircleCI server v4.x.
• The default concurrency limit has been increased to avoid it being reached.
• Docker layer caching volumes are now deleted after 3 days if unused. Previously they were deleted after 7 days.
• kong is now placed behind NGINX to simplify loadbalancer setup.
• The loadbalancer has been renamed from circleci-traefik to circleci-proxy.
• Workflow configurations that are stored in PostgreSQL will migrated to the Object Storage.

Known issues

• Telegraf needs to have its configuration overwritten and base64 encoded.
• When migrating from 3.x to 4.x, workflow configuration migrations will run as an init job and the workflows-conductor-event-consumer and the workflows-conductor-grpc-handler pods will not start until the migration completes. Customers with large PostgreSQL databases should plan accordingly. Migration time can be reduced by scaling the workflow-conductor pods.
• Webhook-service may not work with an externalized Vault.
• Vault may not refresh its client token after a month of uptime.
• Retry with SSH for jobs using the machine executor advertises a private IP address. For this reason, retry with SSH for jobs using the machine executor works as standard for public installations, but for private installs you would need to ensure that you can access the private IP advertised. For example, by using a VPN into your VPC.
• CircleCI 1.0 builds are not supported. If an attempt is made to run a 1.0 build, no feedback will be available in the application to indicate the cause of the issue. If a build is run on your installation and does not show up in the CircleCI application, users should be directed to use the CircleCI CLI to validate the project configuration and get details of the possible cause of the issue.

To learn more about Server 4.x installation, migration, or operations please see our documentation.

CircleCI 2.0 is a completely updated CI/CD platform that starts every run with a clean image which is automatically provisioned just-in-time for Linux jobs on the CircleCI application installed in your private cloud. The CircleCI 2.0 platform includes significant performance, stability, and reliability improvements along with first-class Docker support, Workflows (pipelines), Resource Allocation, and Contexts. The Management Console (Replicated) also includes new options for enabling 2.0 Builders and appropriate default settings.

If you have CircleCI installed you may access CircleCI 2.0 features on your current installation with no restrictions under your current agreement and support level. However, you must contact your CircleCI account representative for assistance with upgrading, to obtain migration scripts, and to receive a new license channel.

• CircleCI 2.0.0 is only available on AWS and may be installed with Terraform or manually.
• Teams may create a CircleCI 2.0 .circleci/config.yml file in their repositories to add new 2.0 projects incrementally while continuing to build 1.0 projects which use a circle.yml configuration file.

Documentation for the installable 2.0 application is available at CircleCI 2.0 Documentation for the following topics:

• Administrator’s Overview
• Administration FAQ
• Security Features
• Installing CircleCI 2.0 on Amazon Web Services with Terraform
• Configuring High Availability
• Administrative Variables, Monitoring, and Logging
• Introduction to Nomad Cluster Operation
• Backing up CircleCI Data

CircleCI 2.0 is a completely updated CI/CD platform that starts every run with a clean image which is automatically provisioned just-in-time for Linux and Android jobs on the hosted CircleCI application.

Configuration moves into the code in 2.0, so every developer can configure jobs directly in their working branch, teams can try new things without the risk of slowing anyone else down, and business leaders have the ability to operate large global teams with minimal overhead. CircleCI 2.0 prevents you from writing clean-up scripts because every run starts in the same state, eliminating the risk of polluting a test database or leaving files in places that cause problems for the next run.

The CircleCI 2.0 platform includes significant performance, stability, and reliability improvements along with the following new features:

• First-class Docker Support: Choose any image to run your job steps, customizable on a per-job basis on a particular Git branch. Speed up your run times with advanced layer caching. Build docker images with full docker CLI support and full support for docker compose. Support for all programming languages and custom environments that offer more predictable output. See Specifying Container Images for instructions.

• Workflows: Orchestrate jobs and steps with great flexibility using a simple set of new keys in your configuration. Share temporary files between jobs with workspaces for fan-in, fan-out, parallel, and sequential runs. Hold a workflow for a manual approval and restart a workflow from a failed job. See Orchestrating Workflows for details.

• Resource Allocation: Configure your CPU and RAM needs on a per-job basis at the branch level, see the resource_class documentation for instructions. Paid accounts may request this feature from their Customer Success Manager, non-paid users may request to get started by sending email to support@circleci.com.

• Insights: Access interactive charts and analyses in seconds. Visualize trends in your build history to identify and pinpoint bottlenecks. Understand all of your builds at a glance. View the builds that fail most, so you can fix the slowest tests to improve efficiency. See the Collecting Test Metadata documentation for information.

• Debugging with SSH and CLI: Perform local job runs, configuration validation and SSH in to builds for access to log files and debugging running processes. See Using the CLI documentation to learn about running local jobs and refer to Debugging Jobs over SSH for SSH instructions.

• Parallelism: Automatic provisioning of containers as they are freed without waiting for other jobs to finish. See the Parallel Job Execution documentation for examples.

• Advanced Caching: Speed up builds by caching files from run to run using keys that are easy to control with granular caching options for cache save and restore points throughout your jobs. Cache any files from run to run using keys you can control, see the Caching Dependencies documentation for strategies and steps.

• Demonstration Applications: See the Language Guides and Demo Repos to learn CircleCI configuration by example for applications written in Go, Javascript, PHP, Python (Django and Flask), Ruby on Rails, Java, Elixir, and Clojure.

• New Documentation: New and restructured documentation including an Overview, Hello World, Sample 2.0 config.yml File, simplified instructions for Migrating from 1.0 to 2.0, plus examples for Configuring Databases and Creating Custom Docker Images. Refer to the Migration FAQ for common questions and known limitations.