What about Guile?
Guile is another great Scheme implementation, one I use quite often since it works quite well on Windows and is included on many *nix systems already. Additionally it has fantastic documentation (as seems to be the case for most GNU Projects) which I like to read quite often to learn more about Scheme.
(define (test i ret)
(cond ((>= i 10000000) ret)
(else (test (+ 1 i) (+ ret i)))))
(display (test 0 0))
(newline)
Running this script takes about ~0.08s on my Laptop with 3.0.8, or ~0.15s with 2.2.7 as compared to Nujel which takes ~1.3s for a similar Program making it about 10x faster than the current Nujel tree walker!
Pros
- Continuations!
- Batteries included, contains pretty much everything needed
- Quite fast, although the Lua Interpreter is still ~2x faster than Guile 2.2.7, Guile 3.0.8 seems to be about as fast as the Lua interpreter.
Cons
- SLOW build time, took ~13 Minutes with 8 Cores full blazing, can't even use all cores since then my entire machine locks up...
- ? Emscripten/WASM support is unclear right now
- Quite big, guile 3.0.8 has a .so that is 5.5M on my system, the one included by Arch built from 2.2.7 is only 1.2M, but is quite a bit slower
In general I think for WolkenWelten Guile 2.X is more interesting than 3.X since it seems that the addition of a JIT is the main change which won't help for WASM and might be the cause for the increase in .so size. Additionally Guile 2.2.7 can be builtin ~3m23s on my Laptop with 8 Cores. Mainly I think that the main problem is WASM compatibility, since that is something I am not willing to give up. So that means looking into compiling Guile with Emscripten.