FLTK Fast Light Toolkit

GTK QT FLTK is a cross-platform GUI toolkit for UNIX/Linux* (X11 and Wayland), Microsoft Windows, and macOS. FLTK provides true GUI functionality without the bloat and supports 3D graphics via OpenGL, and its built-in GLUT emulation. FLTK is designed to be small and modular enough to be statically linked, but works fine as a shared library. FLTK also includes an excellent full builder called fluid that can be used to create graphical interfaces in minutes. FLTK is provided under the terms of the GNU Lesser Public License, Version 2.1 with exceptions that allow linking. Fast Light Toolkit FLTK

The image compares GTK and Qt, represented by slow snails, with FLTK represented by Sonic the Hedgehog moving at extreme speed. The joke is that FLTK is lightweight and fast compared with larger GUI toolkits, so it is sent as a humorous reaction to performance-focused software choices or debates about framework bloat.

• @gentoomemes / 21225 2026-06-27