The current maintainers are officially Dmitry Polyanovsky and Jesse Gumm (same guy who maintains Nitrogen, from which N2O was forked, and also the SimpleBridge web server abstraction library), I believe.
You're right it's not terribly active at the moment. It has rough edges, but it's very much usable.
Phoenix arguably supports most of the same patterns as CB, but on top of Elixir.
EDIT: Oh, by the way, you can actually write Chicago Boss apps using Elixir and LFE instead of plain Erlang, if you'd like. This is officially supported.
Also interesting is that Evan Miller is the original developer of Chicago Boss, and he shows up a lot here. You will see it on the list of his software on the home page.
I think he has since moved on. Notice some nice CB components, like ErlyDTL, are also his work. He shows up a lot here, so I thought people would be interested in it with regards to his other pieces about statistics, modeling, and other topics.
Not surprising. Was not even familiar with the library until I saw the link in these threads to the Github wiki page for ChicagoBoss mentioning features and I saw ErlyDTL, and went to evanmiller's page.
I dug a little deeper because having used Django in a very small does years ago, I have no idea what made its templating so desirable or unique that over stacks copy it.
I assume up on deck: queue jokes about templating non-Erlang in Erlang and how people clamor for anything else.
You're right it's not terribly active at the moment. It has rough edges, but it's very much usable.
Phoenix arguably supports most of the same patterns as CB, but on top of Elixir.
EDIT: Oh, by the way, you can actually write Chicago Boss apps using Elixir and LFE instead of plain Erlang, if you'd like. This is officially supported.