CircleCI Status

Resolved: On July 13 between 15:30 UTC and 22:40 UTC, we experienced delays starting jobs on Docker (Gen 2) resource classes due to capacity constraints from our cloud provider. The same issue recurred on July 14 between 15:45 UTC and 22:50 UTC.

Delays reached up to 25 minutes on July 13 and up to 24 minutes on July 14. The medium+ and 2 X-large+ resource classes saw the longest waits. Earlier updates in this incident reported figures based on average wait times, which didn't reflect the maximum impact some customers may have experienced.

Wait times have now returned to normal. We are continuing to work with our cloud provider to add capacity ahead of the next peak period. Thank you for your patience.

Identified: On July 13 between 15:30 UTC and 22:40 UTC, we experienced delays starting jobs on Docker (Gen 2) resource classes due to capacity constraints from our cloud provider. Delays reached up to approximately 1 minute 48 seconds.

We are continuing to experience these delays again since approximately 15:45 UTC. So far, delays have reached up to approximately 1 minute 19 seconds.

We are working with our cloud provider to add capacity and will update this incident as the situation changes.

Postmortem: ## Summary

From 18:00 UTC on July 13, 2026 to 23:18 UTC on July 14, 2026, some customers running jobs on CircleCI's macOS fleet experienced jobs that hung or failed to progress during GitHub fetch steps. For these customers, GitHub fetch steps which would ordinarily take 1-2 minutes took 20-30 minutes, and timed out. The issue was caused by a capacity and routing problem on the network path between our Mac infrastructure provider and GitHub, and the associated intermittent networking issues slowed down fetches from GitHub. During the entire incident, our team worked directly with our Mac infrastructure provider to identify and reroute traffic away from the affected network paths. We resolved an initial occurrence at 19:40 UTC on July 13. The issue recurred at 21:52 UTC that same day, we reopened the incident, and it was fully resolved by 23:18 UTC on July 14.

Our macOS fleet had a similar issue several weeks ago. From 20:18 UTC on June 24, 2026 to 03:09 UTC on June 25, 2026, customers experienced a similar incident affecting the ability of macOS jobs to reach GitHub. That incident was also caused by a network routing problem in our Mac infrastructure provider.

We thank our customers for their patience while we worked through this incident. Please see below for specific actions which CircleCI and our Mac infrastructure provider will be taking. Please reach out to our support team with any questions or concerns.

The status pages for this incident can be found here and here.

Background

CircleCI's macOS jobs are hosted on a third-party Mac infrastructure provider. That provider connects to the broader internet, including services like GitHub, over multiple redundant upstream network paths. When one of those paths is experiencing reduced capacity or a routing problem, jobs that are fetching code or dependencies from a destination along that network path can slow down or hang intermittently, even when CircleCI's own platform, the third-party infrastructure provider, and the destination service are all operating normally.

What Happened

(All times UTC)

At 18:00 on July 13, some customers running macOS jobs began experiencing intermittent failures and delays fetching code and dependencies from GitHub. We opened an investigation and alerted our customers via our status page at 18:55. By 19:04, our Mac infrastructure provider identified increased latency on one of its network paths and rerouted traffic around it. Fetch times recovered, and we moved the incident to Monitoring at 19:29, and to Resolved at 19:40.

At 20:44 UTC, customers reported that the issue had returned. We reopened the incident and updated our status page to Investigating at 21:52. Over the following two hours, we worked closely with our infrastructure provider to gather diagnostic data in an effort to isolate the affected network path. In the meantime, we published guidance recommending that customers increase their no_output_timeout setting to 15–20 minutes, to allow more time for GitHub fetches to complete during the intermittent slowdowns, and moved the status page to Monitoring at 23:35.

After publishing the workaround guidance at 23:35 UTC on July 13, we expected the underlying network issue to improve overnight. It did not. At 13:59 UTC on July 14, we confirmed that customers were still experiencing intermittent failures and moved the status page back to Investigating. Our engineering team reproduced the failure directly using our own testing tools, which helped confirm this was a general git-fetch issue rather than something specific to any particular build tool, container image, or software update. At 15:35, we updated the status page to share that our infrastructure provider was testing changes to its network configuration to isolate the source of the issue. At 16:31, we updated the status page again to share that we'd identified the cause as reduced inbound bandwidth on a specific route, and that we were working with our provider to shift traffic to a different route. At 16:36, our infrastructure provider identified the affected network paths and shifted traffic away from them, fetch times recovered, and at 16:58, we updated the status page to Monitoring.

By early afternoon, some customers were again seeing slow fetch times, and we moved the status page back to Investigating at 20:18. Our infrastructure provider identified two additional network paths with degraded performance and shifted traffic away from them by 22:07. Fetch times stabilized over the following hour, and we marked the incident Resolved at 23:18.

In total, customers running Mac jobs may have experienced intermittent job slowdowns or failures for portions of the window between 18:00 UTC on July 13 and 23:18 UTC on July 14. Our infrastructure provider has since reported clean test results across its network and believes the underlying capacity issue originated further upstream, closer to GitHub, rather than within its own network. We are continuing to monitor this closely.

Future Prevention and Process Improvement

We are taking the following steps to prevent a recurrence and improve our response time:

We are building additional automated monitoring for macOS fleet GitHub-fetch performance. Our extensive automated monitoring did not catch this incident. We are now adding end-to-end monitoring for GitHub fetches in particular, in order to detect similar issues proactively.

We are working directly with our Mac infrastructure provider on faster, more proactive detection. We are asking our provider to build monitoring that can detect a degraded network path and reroute around it automatically, rather than relying on CircleCI to identify and request a reroute during an active incident.

We are turning the diagnostic tooling we built during this incident into a standing capability. This will let us detect and reproduce this class of network failure on demand going forward, rather than assembling test infrastructure during an active incident.

We are reviewing our incident response process for a sufficient confirmation window before marking a network-related incident Resolved. This incident briefly recurred after an early, premature resolution; we are formalizing a minimum period of confirmed-clean monitoring before closing incidents of this type. We will continue to provide regular updates along the way as investigation and remediation continues.

We are actively moving from a single provider for Mac infrastructure to multiple providers. This will allow CircleCI to route incoming customer workloads to the most available and best-performing provider.

Customer experience is our top priority, and we commit to continually improving the reliability of our systems to match the trust that our customers place in us. Please reach out to our support team with any questions or concerns.

Resolved: We continue to see significant VCS fetch time recovery over the last couple of hours. We're going to resolve this incident, and our engineering team will continue to monitor closely. We greatly appreciate your patience as we worked through this with our Mac infrastructure provider. Please reach out to our Support team if you have any issues.

Monitoring: Our Mac infrastructure provider has shifted more traffic to working network providers and we're starting to see significant recovery again in VCS fetch times. As always, our engineering team will continue to monitor this closely and we'll provide another update soon.

Investigating: We're starting to see VCS fetch times rising again. Our engineering team is actively investigating and working with our Mac infrastructure provider to resolve this. Again, we appreciate your patience.

Monitoring: We're continuing to see slow, progressive recovery in VCS fetch times. We're going to continuing monitoring and update again soon. We appreciate your patience.

Monitoring: Our Mac infrastructure provider has shifted the inbound routes and we are seeing recovery in VCS fetch times. We will be continuing to monitor this issue over the next few hours. We'll update again soon.

Identified: We've identified the issue as some inbound routes from the affected VCS provider causing significantly lower available bandwidth which is negatively impacting repo fetch times. We're working with our Mac infrastructure provider to attempt to shift inbound traffic to a different route, however this process may take an extended period of time to complete. We will continue to provide updates as they become available.

As we've shared in previous updates, increasing the no_output_timeout to 15-20 min continues to help: https://support.circleci.com/hc/en-us/articles/360007188574-Build-has-Hit-Timeout-Limit

Identified: Our Mac infrastructure provider is testing changes to their network configuration in an effort to isolate the source of the issue. We're actively validating whether this resolves the impact and will follow up with another update soon. In the meantime, increasing the no_output_timeout to 15-20 min continues to help: https://support.circleci.com/hc/en-us/articles/360007188574-Build-has-Hit-Timeout-Limit

Identified: Unfortunately there are still some customers that may be experiencing jobs that hang or fail to progress during Github fetch steps due to ongoing intermittent networking issues with our Mac infrastructure provider. Our engineers are actively working with them to resolve this. We appreciate your patience.

In the meantime, we've seen success with increasing the no_output_timeout to 15 - 20 min to allow more time for Github fetches. This can be done by following this community guide: https://support.circleci.com/hc/en-us/articles/360007188574-Build-has-Hit-Timeout-Limit

Monitoring: We've identified the issue. Some customers may experience jobs that hang or fail to progress during Github fetch steps due to intermittent networking issues. Our engineers are actively monitoring.

In the meantime, we've seen success with increasing the no_output_timeout to 15 - 20 min to allow more time for Github fetches. This can be done by following this community guide: https://support.circleci.com/hc/en-us/articles/360007188574-Build-has-Hit-Timeout-Limit

Investigating: We've been able to reproduce the issue, but it still appears to be very much intermittent. We're continuing to work with our Mac infrastructure provider to help diagnose the issue. We'll update again soon.

Investigating: We're still investigating these intermittent network issues. We'll update again shortly, we appreciate your patience.

Investigating: We're received some reports of intermittent network issues between our mac infrastructure and a VCS provider again. We are investigating and will provide updates.

Resolved: GitHub API error rates have recovered to normal levels.

During the incident, some customers may have seen pipelines fail to start or not receive status updates. Some pipelines may be stuck in a running state.

• You should re-push commits or use the UI to manually trigger pipelines that didn't start.
• Pipelines in a stuck running state should be canceled and rerun.

If you encounter any issues please contact CircleCI support.

Monitoring: We are seeing signs of recovery from the GitHub API.

We will stay in a monitoring state to verify that the API error rate has recovered.

Identified: We are also seeing errors processing push event webhooks due to the upstream API outage.

Users may need to retry pipelines for these push events.

Identified: We have identified an issue with GitHub API requests that may cause some customers to see workflows stuck in a running state or workflows fail to start.

GitHub has reported incidents on the APIs

https://www.githubstatus.com/incidents/ph5nns5y4gxj https://www.githubstatus.com/incidents/8vfyvq16hzh9

We are monitoring the stability of GitHub APIs and will update this page as more information is available.

Resolved: An incident affecting GitHub's API caused CircleCI customers to experience errors loading the web app and signing in, along with pipelines and scheduled workflows failing to start or running late. GitHub has resolved the underlying incident (https://www.githubstatus.com/) and all affected functionality has returned to normal.

Customers whose jobs or pipelines failed may rerun them. Scheduled pipelines and workflows that were missed during the incident will not run automatically and will need to be re-triggered.

We thank you for your patience.

Monitoring: What's happening The upstream incident affecting GitHub has been mitigated and is now being monitored on GitHub's side. You can follow GitHub's status at https://www.githubstatus.com/.

What can you expect Access to the CircleCI web app, sign-in, and pipeline and workflow processing are returning to normal. You may still see intermittent errors or delayed scheduled pipelines and workflows as systems stabilize. Thank you for your patience while we monitor for full recovery.

Identified: We are continuing to see high failure rates from GitHub APIs which are impacting login and workflow processing.

We will continue to monitor the GitHub API for recovery.

Investigating: We're investigating an issue where customers may see errors loading the CircleCI web app and signing in, along with pipelines and scheduled workflows failing to start or running late. This is related to an ongoing incident affecting GitHub. You can follow GitHub's status at https://www.githubstatus.com/incidents/gxycch3076xk. Our engineers are actively investigating.

We will provide another update as soon as we have more information to share.

Resolved: GitHub API error rates have recovered to normal levels.

During the incident, some customers may have seen pipelines fail to start or not receive status updates. Some pipelines may be stuck in a running state.

• You should re-push commits or use the UI to manually trigger pipelines that didn't start.
• Pipelines in a stuck running state should be canceled and rerun.

If you encounter any issues please contact CircleCI support.

Monitoring: We are seeing signs of recovery from the GitHub API.

We will stay in a monitoring state to verify that the API error rate has recovered.

Identified: We are also seeing errors processing push event webhooks due to the upstream API outage.

Users may need to retry pipelines for these push events.

Identified: We have identified an issue with GitHub API requests that may cause some customers to see workflows stuck in a running state or workflows fail to start.

GitHub has reported incidents on the APIs

https://www.githubstatus.com/incidents/ph5nns5y4gxj https://www.githubstatus.com/incidents/8vfyvq16hzh9

We are monitoring the stability of GitHub APIs and will update this page as more information is available.

Resolved: GitHub API error rates have recovered to normal levels.

During the incident, some customers may have seen pipelines fail to start or not receive status updates. Some pipelines may be stuck in a running state.

• You should re-push commits or use the UI to manually trigger pipelines that didn't start.
• Pipelines in a stuck running state should be canceled and rerun.

If you encounter any issues please contact CircleCI support.

Monitoring: We are seeing signs of recovery from the GitHub API.

We will stay in a monitoring state to verify that the API error rate has recovered.

Identified: We are also seeing errors processing push event webhooks due to the upstream API outage.

Users may need to retry pipelines for these push events.

Identified: We have identified an issue with GitHub API requests that may cause some customers to see workflows stuck in a running state or workflows fail to start.

GitHub has reported incidents on the APIs

https://www.githubstatus.com/incidents/ph5nns5y4gxj https://www.githubstatus.com/incidents/8vfyvq16hzh9

We are monitoring the stability of GitHub APIs and will update this page as more information is available.