Molasses is the official gopher client of the ESS. It is a GUI client
that supports multiple tabs without sacrificing easy keyboard
navigation.  Molasses is open source. Source code and binaries for
Windows, Macintosh, and Linux are available on github.

If you're interested in hosting your own gopher, you may want to check
out Gopher21. Gopher21 is a modern gopher server and the software
hosting this very gopher. It is still under development and currently
lacks anything in the way of useful documentation. But the curious can
follow its progress on github.
Molasses github
Gopher21 github
Home page for new Molasses users