Some of them on a regular basis (Rust and Go people especially), others frequently pop up when their languages are discussed.
Most users on Hacker News use pseudonyms to better avoid the problems possible with having an online presence anywhere, though not all of us can be bothered. I suspect one regular commenter here, though, is associated with the Groovy/Grails developers at Pivotal.
Back in 2009, Grails was the big theme in many JUGs in Germany.
We even added Groovy support to our JSF internal SDK as a means to buy into the "has Groovy support" checklist.
Nowadays, if it wasn't for Graddle, I guess it would be just maintenance related projects. At least from what I see as JUG talks.
[1] http://groovy.329449.n5.nabble.com/You-can-now-write-Android...