Previous incidents

Resolved.

From 08:47 to 09:11 UTC, all incoming web traffic returned 500 errors.

We have stopped the deployment and rolled-back to the previous version. We're no longer seeing dropped requests.

A previous deployment changed some indexes to make some queries faster, but it also resulted in slower queries in other areas.
We have performed a series of optimizations that should lead to faster queries overall.
We've added load testing for the most common queries to catch future regressions and are monitoring timings in production.