On 2021-06-16 at 8:30 CET, our engineers identified an issue with elevated 500 errors on some non-essential client-script API calls.

What happened?
After our scheduled maintenance, some non-essential client-script API calls were getting elevated 500 errors. This didn't have any impact on Hotjar users. Visitors to sites using Hotjar could have seen some 500 errors in case they checked their DevTools Console, but it wouldn't affect their experience while navigating the site.

Why did this issue occur?

When coming out of maintenance mode, one internal service was overloaded and failed to scale up properly.

What will we do to prevent this from happening in the future?
We will hold an internal postmortem to establish any relevant follow-up actions.