Customer impact

On June 28, 2026, between 16:00 and 18:00 UTC, a subset of customers using UiPath Maestro experienced increased latency in workflow executions. This included delays in the start of execution of Maestro instances, and slower task execution generally. The impact was concentrated in the Europe region, and the total customer-impact duration was approximately two hours. As a precaution, capacity adjustments were also applied in the US region. All times are in UTC.

Root cause

Maestro's workflow execution relies on an underlying workflow orchestration platform made up of multiple components — components that process and execute workflow tasks, and a central component that coordinates and dispatches that work between them.

In response to an earlier, unrelated load issue, the capacity of the task-processing components had been increased to handle higher demand. The capacity of the central coordinating component, however, was not increased in proportion. As the additional task-processing capacity came online, it generated more concurrent requests to the coordinating component than that was configured to accept. Once its concurrency limit was reached, the latter began rejecting (rate-limiting) a portion of the incoming task-polling requests.

When these requests were rejected, the system repeatedly retried, which triggered further rate-limiting, and slowed the overall pace of Maestro workflow execution.

Detection

The incident was detected from an internal report from of the UiPath internal teams. An incident bridge was started at 16:00 UTC. A public status update was posted at 16:39 UTC, notifying customers of increased latency affecting Maestro workflow executions in Europe.

Response

Immediately after detection, engineering began investigating. By 17:05 UTC, the team had identified the underlying cause as the workflow orchestration service's concurrency limit being exceeded. Mitigation was applied by increasing the capacity of the workflow execution and orchestration components in Europe. Performance improved significantly following the change, and the status page was updated to monitoring at 17:35 UTC. After confirming stability, the incident was marked as resolved at 18:00 UTC, with Maestro workflow executions returning to normal.

Follow-up

1. Capacity validation through load testing: Run focused load testing to establish the correct orchestration concurrency limits and capacity settings for Maestro under realistic production demand, so these limits are validated ahead of time rather than tuned during an incident.
2. Targeted alerting: Add earlier, more direct alerting on orchestration concurrency saturation and Maestro workflow-execution latency, so similar conditions are caught before they reach customer impact.