Neo4j is a high-performance, NOSQL graph database with all the features of a mature and robust database. The programmer works with an object-oriented, flexible network structure rather than with strict and static tables — yet enjoys all the benefits of a fully transactional, enterprise-strength database. For many applications, Neo4j offers performance improvements on the order of 1000x or more compared to relational DBs.
Neo4j is an open source (you're reading it) project available in a GPLv3 Community edition, with Advanced and Enterprise editions available under both the AGPLv3 and commercial licenses, supported by Neo Technology.
More about Neo4j.
Neo4j is available both as a standalone server, or an embedded component. You can download or try online.
We encourage everyone to experiment with Neo4j. You can build extensions to Neo4j, or make contributions to the product itself. Please note that you'll need to sign a Contributor License Agreement in order for us to accept your patches.
Please note that this GitHub repository contains mixed GPL and AGPL code. Our community edition (in the community/ directory) is GPL. Our advanced and enterprise editions (advanced/ and enterprise/, you get the drill) are Affero GPL and so have different licensing implications.
This build will build all of our product, including documentation. If you don't have the tools for documentation (e.g. asciidoc, LaTeX), then use pass the -DskipNativeDeps flag to Maven.
We also supply commercial licenses. Please contact Neo Technology for more information.