An XMPP to SMS gateway for Catapult (also known as Bandwidth AP), using XEP-0100. The "SGX" stands for "Soprani.ca Gateway to XMPP", as this is associated with the Soprani.ca project.
Note that the canonical location for this repository is https://gitlab.com/ossguy/sgx-catapult . Please use that location for all pull requests, issue reports, etc. Other locations are likely out-of-date.