It's Go!  It's PAM (Pluggable Authentication Modules)!  It's GoPAM!

This is a Go wrapper for the PAM application API.  There's not much
else to be said.  PAM is a simple API and now it's available for use in Go
applications.

There's an example of a "fake login" program in the examples
directory.  Look at the pam module's godocs for details about the Go
API; for a more general PAM application API reference, peep

http://www.kernel.org/pub/linux/libs/pam/Linux-PAM-html/adg-interface-by-app-expected.html

In the future, maybe the module API will be wrapped too.  I don't know!