[Maxime Devos] > Also, somehow this version of the package builds on Debian sid, > so maybe Debian knows more, though I'm not finding anything > relevant in the Debian package myself. true, and I quickly ran a debian:sid container to see what they did, but they chose the same solution. That is, the exiv2 binary from their package returns the error as well (without the exception raising). So, I guess they dont run the test suite then as there's no change in their packaging. It gave me enough confidence though to use it locally and try to package it up in guix the same way. But I agree it's rather unsatisfactory. marcel