Why SQLite has become a serious production database in 2026. Turso/libSQL, Litestream replication, Cloudflare D1, embedded replicas with microsecond reads, the workloads where it beats Postgres, and the ones where it doesn’t.
A practical comparison of Server-Sent Events and WebSockets in 2026. The protocol differences, AI token streaming, chat with cancellation, code in FastAPI, Hono, and Axum, scaling and CDN/proxy behavior, and a clear decision rule.
How OpenTelemetry actually works in 2026. The collector, traces / metrics / logs / context propagation, instrumenting Python, Go, and Rust services, sampling that doesn’t kill recall, and the production-grade end-to-end setup.
Production caching strategies — cache-aside vs write-through vs write-behind, stampede prevention, hot keys, TTL design, the Redis-vs-Valkey split, and a checklist for adding caching that doesn’t bite back.
Production patterns for idempotency keys, retry strategies, the outbox pattern, and the truth about exactly-once delivery. The patterns every backend engineer needs to handle network failure correctly.
When to pick Kafka vs NATS vs RabbitMQ. Semantics, throughput numbers, ordering and persistence guarantees, operational cost, and a decision tree based on what you’re actually building.
Build a production TypeScript backend with Hono on Bun. Type-safe routing, Zod-validated inputs, Drizzle ORM with Postgres, structured errors, OpenAPI from types, and a project layout that scales past the hello-world phase.
How to design a distributed rate limiter end-to-end. The four classic algorithms, when to pick each, a Redis Lua implementation, distributed coordination, and the gotchas (clock skew, hot keys, fairness).
A backend engineer’s working mental model for distributed systems. Failure modes, CAP, replication, partitioning, consistency, time and ordering, idempotency — explained without the textbook.
What async Rust feels like once it clicks — Tokio’s runtime, tasks vs futures, JoinSet, channels, cancellation, select!, and the shape of every concurrency pattern you’ll need on the backend.