[fl7305]

You could easily write a RISC-V CPU emulator for your older/smaller machines, and run the original Nethack code compiled to RISC-V.

[anthk]

Under a 286? At time-freezing speeds. Minix 2 under a homebrew 16 bit CPU already was so-so in usability:

https://homebrewcpu.com/

[fl7305]

I think it would be well enough for Nethack.

Would be interesting if even a Z80 could run Nethack in a CPU emulator.

[anthk]

Nethack 1.3c, maybe. The first release, I mean, the inmediate one after Hack 1.0.3 under BSD's. That with a lot of patience. Nethack 3.4.3... I doub't it even DOS could handle it with 640k and a 286.