Bloom filters shave 90% of negative lookups; HyperLogLog estimates cardinality without storing every user ID. Redis modules on ElastiCache for abuse detection and feed deduplication.
Why Aurora PostgreSQL loves B-tree indexes on OLTP but DynamoDB feels like an LSM—and how cost-based optimization surprises you when statistics go stale on RDS.
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.
Default Docker seccomp is not enough for regulated workloads. EKS Pod Security Standards, seccomp profiles, and Fargate platform version constraints.
Two goroutines updating adjacent counters can saturate memory bus on a c7g.8xlarge. Memory barriers, cache lines, and false sharing—why placement groups do not fix application-level contention.
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.
Too many "too many connections" pages are fixed by raising max_connections—which trades one outage for OOM on the writer. This guide traces deadlocks, pool sizing, RDS Proxy, and prepared statement caching on Aurora.
Cache-aside without an invalidation story ships stale pricing to 2% of users—the hardest 2% to debug. This guide layers CloudFront, ElastiCache, and DAX with TTL, event-driven purge, and when write-through beats cache-aside.
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.
Protobuf on the wire saves bytes; GraphQL saves round trips until resolvers N+1 your Aurora cluster. ALB gRPC, AppSync, and consumer-driven contracts with Pact.
