01Idempotency keys, in practiceA field manual for the engineer who has been bitten once and is now annoyed.
02On the cost of being honest about latencyP99 is a story we tell ourselves. Here is a longer, less flattering one.
03A ledger that refuses to lose a centInvariants for a small double-entry system, and why balance is enforced rather than hoped for.
04Reconciliation as a fixed pointOn two ledgers that disagree politely, and the iteration that brings them to terms.