esper

Esper is really curious. I looked at it while getting a feel for the general landscape of streaming data tools in late 2013 - to be clear, it was a very cursory look, on the timescale of a few hours at most. I quote what my final take-away was at the time: > Seems good but... such a weird project. Codehaus, svn, not high activity, but consistent, stable releases for five years. Maybe just not the kind of thing webdevs get into? Not sure if that's a strike against or not. With the demise of Codehaus it looks like they've moved to github: https://github.com/espertechinc/esper But oddly they don't seem to have migrated their svn history, and the README implies they don't plan to... I certainly hope they didn't lose it when Codehaus shut down. There was, as noted, already 9 years worth of code changes in that repo. That would be unfortunate.

Neat: sounds like an event stream processor. I've done this in the past with temperature sensors using open source libraries like Esper (https://github.com/espertechinc/esper) and in exchange for a bit of additional complexity you can do really interesting things like convert almost natural language alert definitions into running code.