Glimmer DSL for LibUI - Prerequisite-Free Ruby Desktop Development Cross-Platform Native GUI Library - The Quickest Way From Zero To GUI - If You Liked Shoes, You'll Love Glimmer! - No need to pre-install any prerequisites. Just install the gem and have platform-independent GUI that just works on Mac, Windows, and Linux.
Why do you think that https://github.com/andlabs/libui is a good alternative to glimmer-dsl-libui