JUCE is an open-source cross-platform C++ application framework
MAME is a multi-purpose emulation framework
Web Framework built on top of Qt, using the approach of Catalyst
Scripting platform, modding framework and VR support for RE Engine
NativeScript for Android using v8
Cross platform toolkit for creative coding in C++
A modern, C++-native, test framework for unit-tests, TDD and BDD
A framework for building native Windows apps with React
A flight software and embedded systems framework
Fastest feature-rich C++11/14/17/20 single-header testing framework
Static reflection for enums (to string, from string, iteration)
A lightweight game server framework implemented with Actor Model
TreeFrog Framework, High-speed C++ MVC Framework for Web Applications
Light and powerful C++ web framework for web applications
Open source framework simplifying the creation of C++ applications
Industrial-grade RPC framework used throughout Baidu
Cross-platform layout engine which implements Flexbox
MNN is a blazing fast, lightweight deep learning framework
Source code is here - https://sourceforge.net/projects/lcmd-git/
Original source code of Ultimate Toolbox, TCP/IP and Grid for MFC
Real-Time Event Frameworks based on active objects & state machines
A cross-platform GUI library
Borland's Object Windows Library for the modern age
ALFOUR Programming language. Simple, safe, power, multi-platform.