So yesterday (Sep 19) composters were working just fine as my partner was doing her garden but today I noted the Composters were not producing anything. If the composter was in reach of a sprinkler then the animation progress would just keep resetting and if I moved them somewhere else the animation would progress all the way to the end and an item was consumed but there was no output, nothing produced. 

There was an issue with "QuickSmelt" which caused this same issue at the start of the wipe and that was patched and is not the cause of hte current issue. I managed to narrow it to "CraftingController" when I remove this plugin the issue is resolved 

EDIT: Further investigation it appears to be fine. Just needs multiple units to make a single fert