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~/spellbook the writing

Spellbook

Notes from the work, written as spells. Each has a school (its suit), a level (how deep it goes), a casting time (how long it takes to read) and the components you'll need. Pick one to see it on the scroll; unroll the scroll to read it whole.

The three-line pull request. cantrip, cups · inscribed 2 June 2026. casting time 1 minute, range any repository, components a diff, an honest summary

Idempotency keys for people in a hurry. 2nd level, swords · inscribed 20 Aug 2026, newest. casting time 6 minutes, range any client that retries, components Postgres, a unique index, patience
Idempotency keys for people in a hurry

~/spellbook/idempotency-keys-for-people-in-a-hurry.md

Idempotency keys for people in a hurry

2nd level, swords · inscribed 20 Aug 2026

casting time
6 minutes
range
any client that retries
components
Postgres, a unique index, patience

A payment request times out. The client retries. Did the first one go through? Without a key nobody knows, and the safest answer is the one that charges twice.

6 minutes · the whole spell inside