A GUI framework for C# console applications
Free SLOC counts physical lines of code (SLOC) for many languages
Regex Windows GUI app to help learn, create,& test Regular Expressions
All-in-one web-based IDE specialized for machine learning
The smallest header-only GUI library(4 KLOC) for all platforms
Dynamic Extension for TCL/TK
A small C library for building user interfaces with C, XML and CSS
A simple, friendly framework for Free Pascal text mode GUI creation.
Free texture packer
OpenNum lets you distribute solvers with a nice graphical interface
A web UI client for managing git repos on the go
Object Oriented Language
iOS Automation Framework iOS Touch Simulation Library
Python bindings for the Chromium Embedded Framework (CEF)
Garnet Common Lisp GUI Library
Marathon supports testing of Java/Swing and Java/Fx applications.
Light & Dark Vim color schemes inspired by Google's Material Design
Build cross platform HTML desktop apps on .NET
AVR simulator IDE
Make yourself a GUI for DOS from QBasic
GUI maker for linux scripting using 'pipes' for full interaction
JPHP - an implementation of PHP on Java VM