In preparation for #SFD2025, I thought it might be fun to discuss lightweight GUIs. Maybe some of them will inspire you to create your own #FreeSoftware for #SoftwareFreedomDay2025. Please share your favorite Free Software with this list in preparation for Software Freedom 2025 in September. One of my favorites, #raylib. It's designed so students can start programming quickly without having to spend a lot of time learning how to get text and graphics on screen: https://github.com/raysan5/raygui Check out some of the games created for it: https://www.raylib.com/games.html #SDL is a popular graphics library: https://www.libsdl.org/ With addons like sdl3_ttf, sdl3_mixer, sdl3_image, sdl3_gfx, you can easily get text and graphics on screen or listen to music. Have SDL2 programs you want to keep enjoying? Check out the compatibility layer: https://github.com/libsdl-org/sdl2-compat #FLTK has a lot of the features of standard #GUI libraries but still manages to be lightweight with few dependencies. It's been used with #nano-x to create #XFDOS and #nanolinux. #TinyCore also features FLTK applications. FLTK applications even work on handheld and mobile devices. Here's a list of FLTK programs: https://www.fltk.org/links.php?LC+P22+Q While some are designed for older versions of FLTK, I've had no trouble updating many of them to later versions of the library. #nuklear doesn't have as many applications as many other GUIs, but it ports to an impressive number of systems. Here's a list of some programs written with it including a CAD program: https://github.com/vurtun/nuklear/issues/202 nuklear ( https://github.com/Immediate-Mode-UI/Nuklear ) is lightweight but still offers a lot of functionality. If you're looking for a GUI library that works with your #OpenGL programs, I really like #OTK: https://sourceforge.net/projects/otk/ There are some interesting sample programs for this library. #pdcurses ( https://pdcurses.org/ ) brings the ease of use of the classic curses library to a wide variety of platforms. It can even use a SDL backend so that you can run pdcurses applications with X Windows, Wayland, Android or anywhere else SDL works. Use BSD #form and #menu libraries with it to add more GUI functionality.