The original .gitignore caught *.deb in the source tree but not:
- debian/.debhelper/ (cache populated by every dh_* helper)
- debian/debhelper-build-stamp, debian/postit.debhelper.log,
debian/postit.substvars (regenerated per build)
- debian/tmp/ (staging tree for dh_install)
- postit_*.{deb,changes,buildinfo} in the parent workspace
(where dpkg-buildpackage drops artifacts)