Tagged
CAP is not a trivia question—it is the reason your global DynamoDB table shows stale inventory or why Aurora Global reads lag 80 ms behind the writer. This guide maps partition tolerance, consistency, and availability trade-offs to concrete AWS controls.
You rarely implement Raft on EC2—you buy it in Aurora, DynamoDB, and EKS etcd. This guide explains quorum math so you trust managed services and avoid rolling your own coordinator.
Last-write-wins is not a CRDT—it is how Global Tables lose cart merges. When to use counters, OR-Sets, and conflict-free merges vs when to keep a single Aurora writer.
Redlock debates matter because ElastiCache is not a consensus system. Consistent hashing for sharding workers and ALB target stickiness—with DynamoDB conditional writes as the boring alternative.
Exactly-once is a myth end-to-end—but idempotent consumers plus event stores get you close. CQRS read models on DynamoDB streams, Kinesis, and EventBridge replay semantics.
July 2026 field note: Aurora failover windows still force app timeouts above tens of seconds; DynamoDB hot partitions and short transactions remain the scaling levers — with a partition-math worksheet you can reproduce.
A curated, production-tested guide to microservices patterns on AWS — what to use, what to skip, and what changed in 2026 (App Mesh EOL, VPC Lattice, Powertools idempotency, Step Functions sagas).