From the webpage:
A Clojure library designed to make it easy to work with embedded Titan graphs.
Check clojars for the latest jar. The best thing to do is set up lein checkouts and clone the library directly.
This is very much a work in progress. Titan is a young project and has yet to even hit 0.2. Hermes will probably always be a work in progress until Titan hits 1.0. So, use this in production at your own peril.
The best bet right now is to read the source code. We are still writing the docs and example projects.
If you are interested in graph databases, you should know about Titan graphs. If you don’t, correct that before reading about Hermes.
Avoid use in production but do consider contributing examples, documentation.