The REST API design decisions that make or break developer experience — versioning strategy, error format, pagination, idempotency keys, rate limiting headers, and the spec-first workflow that prevents breaking changes.

Rust is the most admired language for four years running, but most JS and Python developers do not know where to start. This guide explains ownership with analogies, when Rust is the right tool, and the use cases where it beats everything else.

The system design interview framework that consistently gets offers at FAANG — requirements scoping, capacity estimation, API design, component breakdown, database selection, and scaling. With worked examples.

Go concurrency is powerful and dangerous in equal measure. These goroutine and channel patterns — worker pools, fan-out/fan-in, context cancellation, errgroup — are what senior Go engineers actually use in production.

Designing a URL shortener is a classic system design question — but building one that handles 100M requests/day requires careful decisions about encoding, caching, database choice, and read/write separation.

Token bucket, sliding window, fixed window — rate limiting algorithms explained with actual implementation code in Node.js and Redis, plus the distributed systems gotchas that catch everyone out.