I'm looking at upgrading python-sip, since I think Calibre may need it, and presumably it needs updating anyway. Updating the package its self was trivial, but when building packages with it I came across some issues that seem unique to Guix/Nix's directory structure. SIP 5/6 uses sip-build instead of `python configure.py ...'. Updating python-pyqt to use sip@6 mailto:sip@6 with sip-build results in some binaries being installed to a doubled up /gnu/store/.../gnu/store/...-python-wrapper.../bin/... path, since I used INSTALL_ROOT = %output, and set sip-build --target-dir to a relative path. Building python-pyqtwebengine, it is unable to find the .sip files needed since it only searches one global path: openat(AT_FDCWD, "QtCore/QtCoremod.sip", O_RDONLY) = -1 ENOENT (No such file or directory) openat(AT_FDCWD, "/tmp/guix-build-python-pyqtwebengine-5.15.2.drv-0/PyQtWebEngine-5.15.2/sip/QtWebEngineCore/QtCore/QtCoremod.sip", O_RDONLY) = -1 ENOENT (No such file or directory) openat(AT_FDCWD, "/tmp/guix-build-python-pyqtwebengine-5.15.2.drv-0/PyQtWebEngine-5.15.2/sip/QtCore/QtCoremod.sip", O_RDONLY) = -1 ENOENT (No such file or directory) openat(AT_FDCWD, "/tmp/guix-build-python-pyqtwebengine-5.15.2.drv-0/PyQtWebEngine-5.15.2/build/bindings/QtCore/QtCoremod.sip", O_RDONLY) = -1 ENOENT (No such file or directory) openat(AT_FDCWD, "/lib/python3.8/site-packages/PyQt5/PyQt5/bindings/QtCore/QtCoremod.sip", O_RDONLY) = -1 ENOENT (No such file or directory) write(2, ".sip-build-real: Unable to find "..., 61.sip-build-real: Unable to find file "QtCore/QtCoremod.sip" So I'm wondering what the solution to this is. Does SIP 5 & 6 simply not support the Nix style of package management, or is there some simple way for us to make it work?