libnfs-sys
libnfs rust bindings
NFS in userspace.
Note to users: Depending on your system you may need to install some extra libraries for this to link properly. Here's what I used on ubuntu 16.04:
dpkg -l | grep -i libnfs
ii libnfs-dev:amd64 1.9.8-1 amd64 NFS client library (development files)
ii libnfs8:amd64 1.9.8-1 amd64 NFS client library (shared library)