Coveralls incident
Increased latency for Large Repos (5k+ source files)
Coveralls experienced a minor incident on September 30, 2026 affecting Coveralls.io Web and Coveralls.io API, lasting 6h 52m. The incident has been resolved; the full update timeline is below.
Affected components
Update timeline
- monitoring Sep 30, 2026, 01:19 PM UTC
User in Europe and US east coast with large repos (5k+ repos) experienced slow build completion, starting around 2am PST / 5am EST. We have identified the issue and allocated resources to clear a backlog of background jobs. Jobs should clear and builds should complete in the next 45min - 1hr.
- monitoring Sep 30, 2026, 04:25 PM UTC
The root cause of issues with large repos has been fully addressed. We are continuing to clear some backlogged background jobs. We will continue to monitor and report updates here.
- resolved Sep 30, 2026, 08:11 PM UTC
This incident has been resolved.
- postmortem Oct 11, 2026, 06:55 PM UTC
# Update: Major Performance Optimization Released for Heavy Repo Builds Triggered by this latest incident, we've released a major optimization to our code that processes large \(aka. “heavy”\) repos \(>=5K source files\). Tests over the weekend of Fri, Oct 9-Sun, Oct 11 show a near 20x improvement in performance per heavy repos build at lower, weekend volumes. While we expect the optimization to continue to drastically improve build times for these repos \(and reduce instances of increased latency for them\), we won’t know what the aggregate improvement is until we are at full volume this week. We are monitoring to get a sense of where the performance improvement lands, but are hopeful we’ve crossed a significant milestone in how efficiently these builds are processed given the unique challenges many of them pose.