Incident: Trouble with Search

Between 11:51 AM PST and 9:10 PM PST on December 2, 2025, some users experienced issues with the Slack search functionality. Affected users may have encountered a range of symptoms, including the display of incorrect search results, missing messages, noticeably degraded or slow performance, and in some cases, a complete failure to load any search content.We traced this back to a temporary, unexpected surge in resource demand that impacted a critical backend service responsible for processing search results. We increased resources for this service to mitigate impact and stabilize the search functionality, however, during this time, a backlog of unindexed content was created. This backlog prevented content from appearing in search results for some users.To resolve this, we began re-processing the accumulated backlog of unindexed content back into our search systems. Once the indexing process was complete, all messages and content shared during the initial impact window became fully searchable, resolving the issue for all users.