Folks, there's a new JSON Facet API in the just released Solr 5.1 (actually, a new facet module under the covers too).
It's marked as experimental so we have time to change the API based on your feedback. So let us know what you like, what you would change, what's missing, or any other ideas you may have! I've just started the documentation for the reference guide (on our confluence wiki), so for now the best doc is on my blog: http://yonik.com/json-facet-api/ http://yonik.com/solr-facet-functions/ http://yonik.com/solr-subfacets/ I'll also be hanging out more on the #solr-dev IRC channel on freenode if you want to hit me up there about any development ideas. -Yonik