LRU vs W-TinyLFU
Why a burst of one-hit-wonders evicts your most valuable keys under LRU, how Count-Min Sketch admission control fixes it, and when SLRU or 2Q are enough.
HTTP 301 vs 302
The exact trade-off between permanent and temporary redirects, why analytics and revocation force 302, and the hybrid that gets most of both.
Geohash hot shards
A step-by-step account of how uniform spatial grids fail on non-uniform populations, why quadtrees fail differently, and the three production fixes.
Edge KV specifics
Exact quotas, capacity arithmetic, propagation behaviour, and what the 5 MB ceiling means for an edge-terminated design.
Idempotency
Why exactly-once delivery is impossible, what exactly-once processing actually means, and the four mechanisms that make retries safe.