Let me chime in and say that plain Win32 API is a perfectly viable option if you are using C++ (or another "OO" language) and if you are willing to sink a couple of weeks into writing your own MFC-like wrapper.

Clearly this is not an option for those who are just starting up with Windows GUI work, but with little experience it is really a matter of 2-3 weeks of ground work and then you have full control over all nuances of the UI, yours to extend and mend as you wish.

If there's one thing that Microsoft is really good at, it's ensuring deep backward compatibility. So anything that's based on Win32 API is going to be stable. If it works now, it will work later.

I have some examples from 10+ years of development updates accumulated here - https://bvckup2.com/wip

The main thing that's hard going down this route is dark mode support. The Win32 USER and common controls just don't not support dark mode, but are actively hostile to it due to the amount of hardcoded light colors and backgrounds in the system. All of the system colors are light regardless of the dark/light system setting, highlights are hardcoded to light blue, disabled controls use a hardcoded color, half of the window messages for changing control colors are silently ignored with theming is enabled. Menus are among the more difficult to deal with as they require extensive owner draw.

On top of this, there are a small handful of system UIs that do support dark mode and make your program look inconsistent with dark mode regardless. Message boxes will switch to dark mode, and so will file dialogs -- which is a problem if you've used the Vista-style customization, as any syslinks will appear in a color of blue that's hard to read against the dark mode background.

The last time I built a native Windows app years ago, I used WTL 3.0. It’s a light weight wrapper on the native Win32 API, lighter than MFC. It took out the unpleasantness of working directly on Win32 API and wrapped it in a simple OO framework. It had access to all features of Win32. It could produce runtime binary in dozens of K, instead of MB or GB.

Microsoft released it open source later on. Looking at the repository, looks like it has been kept up and maintained, up to version 10 now.

Judging from the screenshots, that doesn't produce Windows 11 style UIs, right? I.e. it contributes to the problem exploree at https://ntdotdev.wordpress.com/2023/01/01/state-of-the-windo...

Why not just use C++ Builder or Delphi?

I don’t want to be that person, but if you can think of a decent API for your MFC-style wrapper, an AI should be able to write a decent implementation for you.

> If it works now, it will work later.

Wine is better at it than Windows itself. Especially for really old programs.