The issue has been resolved, and the API is fully operational again.
We are currently reviewing the incident and implementing measures to prevent such incidents from happening in the future.

At 09:01 we began sending out a large email-newsletter for a customer, using new high-capacity email infrastructure we have been building to increase email throughput and reliability.

At 09:04 the first emails began being opened, and traffic increased from open- and click-tracking.

At 09:07 we the combined traffic had increased the amount of traffic to one of our customer database-shards to increase almost hundred-fold over the regular traffic and it began slowing down as it reached it’s co...