- DOOM-iOS (C++, C, GPL-2.0, mature, inactive since 2012)
- Esenthel Engine (C, C++, Custom, beta)
- flixel-gdx (Java, 3-clause BSD, beta, inactive since 2017)
- Game Editor (C, C++, GPL-3.0, mature, inactive since 2014)
- GamePlay (C++, C, Apache-2.0, mature, inactive since 2016)
- Gorillas (Objective-C, JavaScript, Java Research License, mature, inactive since 2014)
- HaxePunk (Haxe, MIT, mature)
- Hedgewars (Lua, C, C++, Pascal, Haskell, GPL-2.0, mature)
- LÖVE (C++, zlib, mature)
- NOVA PINBALL (Lua, GPL-3.0, beta, inactive since 2017)
- OpenLara (C++, C, 2-clause BSD, mature)
- osu! (C#, MIT, beta)
- ouzel (C, C++, Objective-C, 2-clause BSD, beta)
- Playir (C++, Apache-2.0, mature, inactive since 2014)
- Ren'Py (C, Python, Ren'Py, LGPL-2.1, mature)
- Shattered Pixel Dungeon (Java, GPL-3.0, mature)
- Simon Tatham's Portable Puzzle Collection (C, MIT, mature)
- Solar2D (C++, MIT, mature)
- Stockfish (C++, GPL-3.0, mature)
- The Battle for Wesnoth (C, C++, Java, Python, Lua, GPL-2.0, mature)
- Tux Paint (C, C++, GPL-2.0, beta)
- Wagic, the Homebrew (C++, C, Objective-C, 3-clause BSD, beta)
- Yet Another Engine (MoonScript, Java, Lua, MIT, beta, inactive since 2016)