Zipkin is a distributed tracing system

📈 Capturing JVM- and application-level metrics. So you know what's going on.

CrateDB is a distributed and scalable SQL database for storing and analyzing massive amounts of data in near real-time, even with complex queries. It is PostgreSQL-compatible, and based on Lucene.

A low-level integer compression library in Java

Content Based Image Retrieval Plugin for Elasticsearch. It allows users to index images and search for similar images.

Graphify is a Neo4j unmanaged extension used for document and text classification using graph-based hierarchical pattern recognition.

Metrics reporter, which reports to elasticsearch