Some packages rely on FUSE to provide support for additional filesystems not supported by the kernel.
In general, FUSE software are primarily developed for Linux but many of them can also run on macOS. Nixpkgs supports FUSE packages on macOS, but it requires macFUSE to be installed outside of Nix. macFUSE currently isn't packaged in Nixpkgs mainly because it includes a kernel extension, which isn't supported by Nix outside of NixOS.
If a package fails to run on macOS with an error message similar to the following, it's a likely sign that you need to have macFUSE installed.
dyld: Library not loaded: /usr/local/lib/libfuse.2.dylib Referenced from: /nix/store/w8bi72bssv0bnxhwfw3xr1mvn7myf37x-sshfs-fuse-2.10/bin/sshfs Reason: image not found  92299 abort /nix/store/w8bi72bssv0bnxhwfw3xr1mvn7myf37x-sshfs-fuse-2.10/bin/sshfs
Package maintainers may often encounter the following error when building FUSE packages on macOS:
checking for fuse.h... no configure: error: No fuse.h found.
This happens on autoconf based projects that use
AC_CHECK_LIBS to detect libfuse, and will occur even when the
is included in
buildInputs. It happens because libfuse headers throw an error
on macOS if the
FUSE_USE_VERSION macro is undefined. Many projects do define
FUSE_USE_VERSION, but only inside C source files. This results in the above
error at configure time because the configure script would attempt to compile
sample FUSE programs without defining
There are two possible solutions for this problem in Nixpkgs:
FUSE_USE_VERSIONto the configure script by adding
configureFlags. The actual value would have to match the definition used in the upstream source code.
However, a better solution might be to fix the build script upstream to use
PKG_CHECK_MODULES instead. This approach wouldn't suffer from the problem that
AC_CHECK_LIBS has at the price of introducing a dependency