xmin/xmax

Notes on what I’m working on — Postgres internals, Windows, storage, and whatever else is on the bench.

Scripting a Live Postgres Backend with pg_scalpel

pg_scalpel puts a Janet interpreter inside a running Postgres backend. From there you can look up any function or struct by name, call the server’s own C, and swap a function out for your own code, with no recompile and no restart. Here’s how it works, and what it costs.

November 5, 2026 · 13 min

PostgreSQL Trace Probes on Windows with ETW

PostgreSQL has fifty-seven static trace probes, but no backend for Windows’ own tracing facility. A patch in the commitfest connects them to Event Tracing for Windows, so Postgres events and kernel events can be recorded in the same trace.

October 30, 2026 · 11 min