OpenRefine is a free, open source power tool for working with messy data and improving it

Ribbon is a Inter Process Communication (remote procedure calls) library with built in software load balancers. The primary usage model involves REST calls with various serialization scheme support.

An XMPP server licensed under the Open Source Apache License.

Stream summarizer and cardinality estimator.

A collection of tutorials for the OpenTracing API

Facebook's Realtime Distributed FS based on Apache Hadoop 0.20-append

A Stack Overflow clone for teams (self-hosted or hosted)

Indexing engine for IndexTank

An open source framework for building data analytic applications.

The metric correlation component of Etsy's Kale system

concurrency, collections, stats/analytics, config, testing, etc

Airlift framework for building REST services

A template-based cluster provisioning system

Tiledesk Android App. Tiledesk Android allows agents to chat with visitors directly from their Android device