Trying to build udev-hid-bpf package but failing because meson can't find a file from the source code directory

I’ve been trying to compile https://gitlab.freedesktop.org/libevdev/udev-hid-bpf/ as a custom package, but it keeps failing to compile due to not being able to find a python script that by all accounts should be in the source directory and is reported by meson as being there before the building starts and it then complains it can’t find it anymore. nix file for the package: { lib,stdenv, fetchFromGitLab, rustPlatform , buildPackages , elfutils, udev, libbpf, zlib , pkg-config, cargo, rustc, ...