Per-Region Service Routing with NATS Subject Mappings
Apps publish to one subject everywhere. Server-side subject mappings, scoped per cluster in a super-cluster, route to the active regional service without application changes.
Writing
Technical articles, observations, and occasional personal reflections.
Why Your JetStream Handler Runs Twice
JetStream message redelivery is not a bug. But the defaults will surprise you.
What Flush() Actually Does in NATS
NATS Flush is not what you think. It's a round-trip confirmation, not a buffer dump.
Recovering a JetStream Cluster After Quorum Loss
A step-by-step guide to recognizing and recovering from JetStream quorum loss.
Why NATS SubscribeSync Uses 512KB Per Subscription
A customer reported NATS using ~100x more memory per subscription than Redis. They were right -- and it's by design.
How NATS Lame Duck Mode Actually Works
The protocol coordination behind zero-downtime NATS server restarts.
Designing NATS Subject Schemas
Subject design is the first decision in a NATS deployment and the hardest to change later. Here's how to get it right.