I’ve been making the regular (accidentally) six-yearly update to Minara, my vector graphics program.
The new version switches from GLUT to Gtk for the windowing system, from GLU to Cairo for the renderer, and from C to pure Scheme for the core application. It’s all written in The GNU project’s Guile Scheme system.
Minara is Lisp all the way down: the application, tools, and graphics files are all written in Scheme. It’s designed as an environment for 2D generative vector art hacking.