Hi Barry, Did you consider creating whl files at install time¹ rather than pip's build time? This way whl can be regenerated whenever one of needed packages is updated and there's no need to rebuild pip package.
[¹] using dpkg (file) triggers (/usr/share/doc/dpkg-dev/triggers.txt.gz) -- Piotr Ożarowski Debian GNU/Linux Developer www.ozarowski.pl www.griffith.cc www.debian.org GPG Fingerprint: 1D2F A898 58DA AF62 1786 2DF7 AEF6 F1A2 A745 7645
