@cblgh I don't know that much about the arcane art of dynamic library loading sadly. I think on Guix an FHS container is probably the best you can do, because the libraries it needs are not put in user profiles, so you can't just rely on some path variable.
As for Alpine... hmm... I guess just hardcoding a fallback to the musl loader is one option. 🤔
@cblgh Did more testing, it's looking for libwebkit2gtk-4.0.so.37, Guix has libwebkitgtk-6.0.so.4.0.3 and libwebkit2gtk-4.1.so.0.8.3, and some symlinked variants with simpler names, but no libwebkit2gtk-4.0. So all the webkitgtk libraries are newer.
Most generically named one is libwebkit2gtk-4.1.so.