Estimation

Back-of-the-envelope math: turning users and payloads into QPS, storage, bandwidth, and cache — the arithmetic that picks an architecture.

Explainers

• Back-of-the-Envelope: the Numbers That Design Systems — Before you draw a box, you do the arithmetic. Powers of two, the latency ladder, and a live calculator that turns daily users and payload size into QPS, storage, bandwidth, and cache — every formula shown.