(require :system) is wrong for Allegro

[e40]

This line:
https://github.com/sellout/external-program/blob/master/src/allegro.lisp#L11
Is not correct in Allegro. The system module is always loaded. If there is a patch for it, you can't just load it with require, you need to rebuild the lisps with update.exe or update.sh.
A customer of ours wrote in about a failure loading your package and this was the problem. Thanks.