track /04-sql-lost-updates

Two Writers, One Row

Concurrency does not announce itself in tests that run one request at a time. Oversell the inventory on purpose, then make it impossible.

Intermediate ~7h postgresqlpythondocker

Your design doc lives here

Sign in, enroll, and decide the shape before you build it — then find out, in the write-up, how much of it survived contact.