June/July 2019’s Cloudflare incidents got the world thinking about additional safeguards against ‘unlikely’ DNS failure. The article below sheds light on five strategies for coping with these unlikely - but possible - DNS failures, as well as general advice for service reliability.

Efficient rate limiting with a growing distributed cluster is hard. These are the challenges we faced when building a horizontally scalable rate limiter.

Ably is a distributed realtime messaging platform. To ensure load and data are distributed evenly and consistently we use consistent hashing algorithms.

In this article we explore the juxtaposition of a Pub/Sub fan-out pattern and a Queue based pattern and why both are sometimes needed.

How Ably's engineers overcome one of the hardest aspects of a globally-distributed realtime messaging service: connection state recovery and stream continuity.