I don't know whether you'd want to work from scratch, to do things entirely your own way, or whether you'd look to extend an existing project. Either is of course reasonable.
If the latter, I get the impression AXPbox is currently the best maintained Alpha emulator. There have been a LOT of Alpha emulators over the years: http://www.avanthar.com/healyzh/decemulation/Alpha.html
Without wanting to sound entitled, my preference is NT for Alpha. That's because Visual Basic 6.0 for Alpha exists, but not for PowerPC. Of course, as a retro computing enthusiast, I'll gladly take any.
https://virtuallyfun.com/2021/11/10/revisiting-windows-nt-4-...
The OpenGL is more 1.0 than 1.1... so it makes for interesting ports. I need to touch on that one too. so much to do..