I'm the original author of pixie, and yeah, I'm a bit surprised to see this hit HN today.
It should be mentioned that I put about a year of work into this language, and then moved on about a year or so ago. One of the biggest reasons for my doing so is that I accomplished what I was looking for: a fast lisp that favored immutability and was built on the RPython toolchain (same as PyPy). But in the end the lack of supporting libraries and ecosystem became a battle I no longer wanted to fight.
Another goal I had was to see how far I could push immutability into the JIT. I learned a lot along the way, but it turns out that the RPython JITs aren't really that happy with VMs that are 99.99% pure. At one point I had a almost 100% immutable VM running for Pixie...as in each instruction executed created a new instance of the VM. It worked, but the JIT generated by RPython wasn't exactly happy with that execution model. There was so much noise in the maintenance of the immutable structures that the JIT couldn't figure out how to remove them all, and even when it could the JIT pauses were too high.
So anyways, after pouring 4 hours a day of my spare time into Pixie for a full year, I needed to move on.
Some other developers have commit rights and have pushed it along a bit, but I think it's somewhat a language looking for usecase.
And these days ClojureScript on Node.js could probably be made to handle most peoples needs.
As a somewhat different data point, we've been developing pycket, an implementation of Racket on top of rpython, for the past 3 years, and while it faces many of the same challenges, we've been very happy with the results. The JIT can remove almost all of the intermediate data structures caused by the functional nature of the language, and we support tail calls and first class continuations. Overall, pycket is almost as fast as chez scheme on average, and faster than every other scheme system we've compared with.
I hope this continues to be developed. I love coding in Racket. I remember when I first started coding in Python years ago and then I ran into Racket (Wanting to learn Functional programming) and I even liked Racket coding even more.
Pycket has different performance characteristics from many of the AOT systems we compared against. On average Pycket is ~2x faster than the Racket VM, ranging from ~3x slower to ~300x faster depending on the benchmark. Last I checked, Pycket's mean performance was about 10% slower than Chez Scheme. The cost you pay for this performance is a rather significant warmup time for many benchmarks.
As for libraries, the only major feature that Pycket does not support is Racket's FFI, most built in functions can be implemented pretty easily if missing.
Clojure developer here, was interested in Pixie since you announced it.
The only reason why I have not tried it out yet is
* No mention of installing it with `nix-env -i pixie`, `apt-get install pixie` or `brew install pixie`. Sorry, but I'm that lazy :(. If you make it Linux-only, a mac user can do `docker run -ti pixie -v /src:.` as well.
* No mention of how to connect from your editor. A small Emacs mode which let's you C-x C-e is all that would have made me use it.
It's lazy and dumb, but that is the truth. So for me the only reason for not being a Pixie developer full time are those 2 UX things.
It should be mentioned that I put about a year of work into this language, and then moved on about a year or so ago. One of the biggest reasons for my doing so is that I accomplished what I was looking for: a fast lisp that favored immutability and was built on the RPython toolchain (same as PyPy). But in the end the lack of supporting libraries and ecosystem became a battle I no longer wanted to fight.
Another goal I had was to see how far I could push immutability into the JIT. I learned a lot along the way, but it turns out that the RPython JITs aren't really that happy with VMs that are 99.99% pure. At one point I had a almost 100% immutable VM running for Pixie...as in each instruction executed created a new instance of the VM. It worked, but the JIT generated by RPython wasn't exactly happy with that execution model. There was so much noise in the maintenance of the immutable structures that the JIT couldn't figure out how to remove them all, and even when it could the JIT pauses were too high.
So anyways, after pouring 4 hours a day of my spare time into Pixie for a full year, I needed to move on.
Some other developers have commit rights and have pushed it along a bit, but I think it's somewhat a language looking for usecase.
And these days ClojureScript on Node.js could probably be made to handle most peoples needs.