Cmake GitHub Repositories (2026) · Open Source Tools

An open source re-implementation of RollerCoaster Tycoon 2 🎢

FluentQt (Fluent-Qt): Fluent / WinUI-style Qt Widgets UI components and Gallery for native C++ desktop apps, with optional PySide6 bindings and WebAssembly.

Open-source engine for Heroes of Might and Magic III

Widelands is a free, open source real-time strategy game with singleplayer campaigns and a multiplayer mode. The game was inspired by Settlers II™ (© Bluebyte) but has significantly more variety and depth to it.

Command the forces of The Project in a battle to rebuild the world after mankind has been nearly destroyed by nuclear missiles. A 100% free and open source real-time strategy game for Windows, macOS, Linux, BSD+

A next generation Python CMake adaptor and Python API for plugins

Another CMake LSP

The Domain-Correct Quantities and Units Library for C++ — full quantity kind safety, ISO 80000 compliant, C++29 standardization candidate.

Free open-source modern C++20/23 framework to create console (CLI), forms (GUI like WinForms) and unit test (xUnit) applications and libraries on Windows, macOS, Linux, iOS, Android, FreeBSD, Haiku, and SerenityOS.

libOBS (OBS Studio) for Node.Js, Electron and similar tools

Cross-platform Swift implementation of UIKit, mostly for Android

Declarative UI toolkit for modern C++20

Return To The Roots (Settlers II(R) Clone)

Live Video Mixer

Next generation of ADIOS developed in the Exascale Computing Program

Examples for the Magnum C++11 graphics engine

A modern C++ module-first build tool — written in pure C++23 modules, fully self-hosted

C++23 client for Kalshi's Predictions API. Created from Kalshi's OpenAPI and AsyncAPI specs, it covers every REST operation and WebSocket channel. The WebSocket client reconnects and resubscribes. Optional transports add retries and rate limiting.

C++23 client for NOAA Storm Prediction Center convective and fire-weather outlooks, mesoscale discussions, watches, and storm reports.

A suite of tools for medical image processing focused on brain analysis