Open source releases from Microsoft
Simple Encrypted Arithmetic Library (SEAL) is an easy-to-use but powerful homomorphic encryption library written in C++. It supports both the BFV and the CKKS encryption schemes.
ShaderConductor is a tool designed for cross-compiling HLSL to other shading languages
A fast, distributed, high performance gradient boosting (GBDT, GBRT, GBM or MART) framework based on decision tree algorithms, used for ranking, classification and many other machine learning tasks. It is under the umbrella of the DMTK(http://github.com/microsoft/dmtk) project of Microsoft.
Open source simulator for autonomous vehicles built on Unreal Engine / Unity, from Microsoft AI & Research
Service Fabric is a distributed systems platform for packaging, deploying, and managing stateless and stateful distributed applications and containers at large scale.