Saturday May 1, 2021


Degraded performance issues for some customers

Issue summary:
On May 1, 2021 between 3:51 a.m. to 4:16 a.m. PDT and 5:30 a.m. to 5:54 a.m. PDT, a small number of customers experienced intermittent failures loading and sending messages in Slack. This included errors loading user names and channel names.

We identified the infrastructure that was causing these errors and retired it from our systems. During the remediation, specifically from 6:28 a.m. to 6:34 a.m. PDT, a small number of customers were unable to load Slack, send messages, or update their profiles.

This issue is now fully resolved.

Note: We have updated some timestamps below to more accurately reflect this event.

11:06 AM PST

We’ve confirmed that performance in Slack should be fully restored. Customers should no longer be experiencing trouble with connecting or logging in. Apologies again for any disruption caused, and we’ll follow-up here with a summary soon.

If you notice any problems, please contact us at

6:34 AM PST

Some customers may be experiencing degraded performance issues. We're currently investigating, and we'll keep you posted as soon as we have more information.

3:51 AM PST

Services affected