Post-mortems and failure reports — what happened, why, and how it was fixed.
View All TagsMailwoman couldn't find Tirana, or Yerevan, or 145 other capitals — not a wrong coordinate, silence. We were going to fix the parser. A ten-minute probe killed that plan, and a stale symlink nearly talked us into a GPU retrain to fix a model that was already fine. Two evals, two silent confounds, and the one dull habit that caught both.
You can point a Nominatim client at Mailwoman now and get a geocoder from a SQLite file, without PostgreSQL or a planet import. We did, and the US worked beautifully while the rest of the world resolved to its American namesake. The bug was one line: we'd told it the answer was always America. This post covers the line, the four cities that still won't move once you delete it, and the ranking database we forgot to switch on — which faked the entire scoreboard until a contradiction gave it away.
Mailwoman is an open-source address parser. This post is a training log entry from May 2026 documenting the v0.5.0 divergence investigation. For current project status, see what ships today.
Mailwoman is an open-source address parser. This post is a historical retrospective on the v0.4.0 training campaign (May 2026). For current project status, see what ships today.