Looks like it's trying to use pkg-config to find the necessary flags for the library: https://github.com/sionescu/iolib/blob/master/src/syscalls/ffi-types-unix.

Looks like it's trying to use pkg-config to find the necessary flags for the library: https://github.com/sionescu/iolib/blob/master/src/syscalls/ffi-types-unix.lisp#L8 https://github.com/sionescu/iolib/blob/master/src/syscalls/f... The proper solution would be to install it somewhere and configure pkg-config to find it, but you could just try putting the headers in /usr/local/include and see if it finds them. I think your system package manager has installed your SBCL/asdf in some weird way. It would be best to just uninstall it all and build SBCL from sources yourself (it has asdf bundled with it). The binary releases for FreeBSD on sbcl.org seem to be ancient versions.