8) Graph Engine (Trinity)

Architecture: Distributed in-memory with strongly-typed key-value store

Graph Engine, formerly Microsoft Trinity, provides distributed in-memory graph processing. The C# and C++ implementation enables cluster-scale deployments.

Key Features

• Distributed architecture: Memory shared across cluster nodes

• Strongly-typed storage: Key-value store with type safety

• MIT license: Fully open-source

• Microsoft heritage: Production-tested at scale

Why It Made the List

Graph Engine represents Microsoft Research's approach to distributed in-memory graphs. The architecture remains relevant for academic and research applications requiring distributed memory capabilities.