Two really good looking GUI libraries that can work for D

[aberba]

This two GUI libs written in C I just found are really good 
looking and looks production ready.

Embedded systems:
LittlevGL is a free and open-source graphics library providing 
everything you need to create embedded GUI with easy-to-use 
graphical elements, beautiful visual effects and low memory 
footprint.

Powerful building blocks: buttons, charts, lists, sliders, images 
etc
Advanced graphics with animations, anti-aliasing, opacity, smooth 
scrolling
Various input devices: touch pad, mouse, keyboard, encoder etc
Multi language support with UTF-8 decoding
Fully customizable graphical elements

https://littlevgl.com/





General Usage:
Nuklear is a minimal state immediate mode graphical user 
interface toolkit written in ANSI C and licensed under public 
domain. It was designed as a simple embeddable user interface for 
application and does not have any dependencies, a default render 
backend or OS window and input handling but instead provides a 
very modular library approach by using simple input state for 
input and draw commands describing primitive shapes as output. So 
instead of providing a layered library that tries to abstract 
over a number of platform and render backends it only focuses on 
the actual UI.

Features
Immediate mode graphical user interface toolkit
Single header library
Written in C89 (ANSI C)
Small codebase (~18kLOC)
Focus on portability, efficiency and simplicity
No dependencies (not even the standard library if not wanted)
Fully skinnable and customizable
Low memory footprint with total memory control if needed or wanted
UTF-8 support
No global or hidden state
Customizable library modules (you can compile and use only what 
you need)
Optional font baker and vertex buffer output

https://github.com/vurtun/nuklear


They are both good looking and modern in their respective 
domains. Both written in C so they may each need a D binding for 
convenient use.