User site
Otus Lisp project page, a purely (mostly) functional dialect of Lisp (extended subset of Scheme R7RS). It's small, embeddable, and crossplatform (x86/x86_64, arm/aarch64, mips, ppc, …). Linux, Windows, BSD's, etc. Has own transparent ffi interface with callbacks.
OpenGL for Engineers tutorial page, a set of simple tutorials for engineers to OpenGL library (not in progress for now).