Live

Buildkite service disruption

## Service Impact _All times UTC unless stated otherwise._ Customers experienced elevated errors and latency across the Buildkite web interface, REST API, Agent API, and job queue during two periods: 18:43:00–19:21:00 and 20:02:00–20:28:00 on September 9, 2026. During these periods, customers encountered failed API requests, delayed job dispatch, and errors in agent operations including authentication, job acceptance, and artifact uploads. Some jobs impacted by the incident did not recover automatically. These jobs had to be manually cancelled and retried to complete successfully. Between 18:43:00–19:21:00: Agent API had an error rate up to 11.2% with no latency impact. REST API had a 9.7% error rate with no latency impact. Web request had a 2.6% error rate with no latency impact. Job queues were delayed by up to 3 minutes. Between 20:02:00–20:28:00: Agent API had an error rate up to 24.7% with no latency impact. REST API had a 4.9% error rate with no latency impact. Web requests had a

The latest update from Buildkite.

State

Resolved

Started

53 d ago

2026-09-09 19:07 UTC

Lasted

6 h 47 min

until 2026-09-10 01:54 UTC

Worst impact

Partial outage

Timeline

6 updates
19:0720:4922:3000:1201:54
Partial outageUpdate postedTimes in UTC

Investigating

1 h 46 min 26%

Monitoring

5 h 1 min 74%

Updates

Times in UTC

As posted by Buildkite

Postmortem2026-09-11 06:03 UTC

## Service Impact _All times UTC unless stated otherwise._ Customers experienced elevated errors and latency across the Buildkite web interface, REST API, Agent API, and job queue during two periods: 18:43:00–19:21:00 and 20:02:00–20:28:00 on September 9, 2026. During these periods, customers encountered failed API requests, delayed job dispatch, and errors in agent operations including authentication, job acceptance, and artifact uploads. Some jobs impacted by the incident did not recover automatically. These jobs had to be manually cancelled and retried to complete successfully. Between 18:43:00–19:21:00: Agent API had an error rate up to 11.2% with no latency impact. REST API had a 9.7% error rate with no latency impact. Web request had a 2.6% error rate with no latency impact. Job queues were delayed by up to 3 minutes. Between 20:02:00–20:28:00: Agent API had an error rate up to 24.7% with no latency impact. REST API had a 4.9% error rate with no latency impact. Web requests had a

Resolved2026-09-10 01:54 UTC

We have seen full recovery for customers since 20:28 UTC. We experienced an autoscaling feedback loop which increased the number of connections to our redis cluster above its ability to respond. This had widespread impact for all of our customers with Web UI, Agent API, REST API and job queue impact between 18:43-19:21 UTC, and again between 20:02-20:28 UTC. A full post incident review will be available later this week.

Monitoring2026-09-09 20:53 UTC

We are seeing improvements across the affected services, and are seeing services return to normal functionality. We are continuing to monitor and are determining the root cause.

Investigating2026-09-09 20:28 UTC

We are continuing to investigate elevated error rates across multiple services, and are working to determine the cause.

Investigating2026-09-09 19:41 UTC

We are continuing to investigate this issue. We are seeing impact on the Agent API which will affect job scheduling, artifact uploads, and an increase in 5xx responses from the Agent API endpoints.

Investigating2026-09-09 19:07 UTC

We've spotted that something has gone wrong. We're currently investigating the issue, and will provide an update soon.

Affected components

4
REST APIWebAgent APIJob Queue

Buildkite in the last 90 days

Full history
90 days agoToday

Incidents in 90 days

26

Days with an incident

26

Median duration

1 h 9 min

This incident

5.9× the median

How long each incident lasted, on the day it started. The outlined bar is this incident.

24 h 25 min
median 1 h 9 min
90 days agoToday

Other Buildkite incidents

All incidents

Follow Buildkite

Your coding agent knows when Buildkite is down, and tells you when a failure is theirs, not yours. You can also get Buildkite incidents in a feed reader or in Slack.

Prompt
Install the outages.live MCP server, so that when something breaks you can tell if the cause is a provider we depend on and not my code. It reads the official status pages of cloud, AI, payment and developer providers and gives you their incidents as MCP tools.

Add it as a remote MCP server named "outages" at https://outages.cc/mcp (Streamable HTTP, no authentication), with your CLI command or your MCP config file.

Then:
1. Make sure it connects and shows the tools get_provider, list_feed and send_feedback.
2. Call get_provider with "buildkite" and tell me if Buildkite has a problem right now.
3. From now on, when a call to a third-party service fails or becomes slow, call get_provider for that service before you change my code.

Paste this into any coding agent. It adds the server with its own MCP setup.

RSS
https://outages.cc/feed.xml?providers=buildkite
Slack
/feed subscribe https://outages.cc/feed.xml?providers=buildkite

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