[pron]

I don't think it's the implementation that's delaying Zig's stabilisation, but the design. I'm also not sure comptime makes the implementation all that complicated. Lisp macros are more powerful than comptime (comptime is weaker by design) and they don't make Lisp implementation complicated.

[LexiMax]

Fair. I'm not a compiler developer, so I'll defer to your expertise on that front.

That being said, I suppose my ultimate wonder is how small a Zig implementation could possibly be, if code size and implementation simplicity was the priority. In other words, could a hypothetical version of the Zig language have existed in the 80's or 90's, or was such a language simply out of reach of the computers of the time.

[pron]

It's not quite as minimal as C, but it definitely could have been made in the 80s or 90s (actually, 70s, too) :) There were far larger, more complex languages back then, including low-level languages such as C++ and Ada, not to mention even bigger high-level languages. High-level languages were already more elaborate even in the 70s (comptime is no more tricky than macro or other meta-programming facilities used in Lisp in the sixties or Smalltalk in the 70s; it certainly doesn't come even remotely close to the sophistication of 1970s Prolog).

I don't think there's any programming language today that couldn't have been implemented in the 90s, unless the language relies on LLMs.