pg-interleave

About

pg-interleave is a PostgreSQL wire-protocol proxy that lets tests pause a specific statement, hold its response, drop a connection after a commit, or inject a deadlock error in a fixed order, without changing application code. It also has a schedule fuzzer that reorders queries to expose races, and record and replay of traces. In the README's benchmark, lost updates appeared in 85 to 98 of 100 runs with the fuzzer versus 0 to 5 without.