Carbon Language's main repository: documents, design, implementation, and related tools. (NOTE: Carbon Language is experimental; see README)

Apache Arrow is a multi-language toolbox for accelerated data interchange and in-memory processing

Google's Operations Research tools:

cuDF - GPU DataFrame Library

The Fast Cross-Platform Package Manager

HeavyDB (formerly OmniSciDB)

Python compiler

Insight Toolkit (ITK) -- Official Repository. ITK builds on a proven, spatially-oriented architecture for processing, segmentation, and registration of scientific images in two, three, or more dime…

A simple header-only C++ argument parser library. Supposed to be flexible and powerful, and attempts to be compatible with the functionality of the Python standard argparse library (though not nec…

Official main repository for LFortran

Learn LLVM 12, published by Packt

C++ dynamic ndarray library, with Python exposure

A general dispatch and override mechanism for Python.

OpenQL: A Portable Quantum Programming Framework for Quantum Accelerators. https://dl.acm.org/doi/10.1145/3474222

A language made for a blog post, but that's also named after me

ArxLang compiler aims to provide arrow datatypes as native datatypes.