GNU social : GNU social is a continuation of the StatusNet project. It is social communication software for both public and private communications. It is widely su...
Celery : Celery is an asynchronous task queue/job queue based on distributed message passing. It is focused on real-time operation, but supports scheduling as ...
pump.io : Social server with an ActivityStreams API. It's a stream server that does most of what people really want from a social network.
Faktory : Faktory is a language-agnostic, persistent background job system.
MediaGoblin : MediaGoblin is a free software media publishing platform that anyone can run. You can think of it as a decentralized alternative to Flickr, YouTube, S...
Fireworq is a lightweight, high-performance, language-independent job queue system.
