YouTrackDB https://github.com/JetBrains/youtrackdb is a fork of OrientDB document+graph database that was second in popularity before SAP's sunset.
The YouTrack team forked OrientDB code, but it wants to keep OrientDB's initial goals. This is a general-use open-source database. It excels in usability for EE application developers by implementing a unique mix of document and graph database features with the addition of support for OOP concepts such as inheritance and polymorphism out of the box.
YTDB supports all major Java types, including primitive and semi-primitive types such as dates or strings, and all types of embedded heterogeneous collections: sets, lists, and maps.
Unlike OrientDB, we rely on the TinkerPop https://tinkerpop.apache.org/gremlin.html infrastructure and the Gremlin language, which we extend using our steps and types.
As our team member, you will work on:
Implementation of the cascading deletions feature in YouTrackDB.
Implementation of our proposal for a match step in TinkerPop ( https://lists.apache.org/thread/m4yf6sq9hch933c7bc563ygpb72rkonm ). That includes the implementation of the ANTLR4 parser for a GQL MATCH statement for the match step and executing the resulting AST.
Strong Core Java/ C/ C++ programming skills.
Applied knowledge of common data structures, algorithms, and architectures.
The ability to analyze and debug complex problems.