Compiling Scheme to WebAssembly(eli.thegreenplace.net)
eli.thegreenplace.net
Compiling Scheme to WebAssembly
https://eli.thegreenplace.net/2026/compiling-scheme-to-webassembly/
14 comments
If you're open to Forth,
https://github.com/remko/waforth
> WAForth is entirely written in (raw) WebAssembly*, and the compiler generates WebAssembly code on the fly.
* https://github.com/remko/waforth/blob/master/src/waforth.wat
https://github.com/remko/waforth
> WAForth is entirely written in (raw) WebAssembly*, and the compiler generates WebAssembly code on the fly.
* https://github.com/remko/waforth/blob/master/src/waforth.wat
Ben Lynn's page https://crypto.stanford.edu/~blynn/compiler/ compiles (a large subset of) Haskell to web assembly (which you can download; a prime number sieve yielded 40KB of code) and runs it in the browser.
That is exactly the kind of thing I was looking for. Thanks you!
WebAssembly Text Format (wat) is fine to use. You declare functions that run imperative code over primitive i32/i64/f32/f64 values, and write to a block of memory. Many algorithms are easy enough to port, and LLMs are pretty great at generating wat now.
I made Orb as a DSL over raw WebAssembly in Elixir. This gives you extract niceties like |> piping, macros so you can add language features like arenas or tuples, and reusability of code in modules (you can even publish to the package manager Hex). By manipulating the raw WebAssembly instructions it lets you compile to kilobytes instead of megabytes. I’m tinkering on the project over at: https://github.com/RoyalIcing/Orb
I made Orb as a DSL over raw WebAssembly in Elixir. This gives you extract niceties like |> piping, macros so you can add language features like arenas or tuples, and reusability of code in modules (you can even publish to the package manager Hex). By manipulating the raw WebAssembly instructions it lets you compile to kilobytes instead of megabytes. I’m tinkering on the project over at: https://github.com/RoyalIcing/Orb
I'm working on a TypeScript/Swift/Dart style language, and currently this hello-world is 1444 bytes:
I think it really helps to have a language designed from the ground-up to obsess over bytes for WASM. Trying to do that with a familiar high-level language with a rich standard library is tricky.
export let main = () => {
console.log("Hello, World!");
};
I think it really helps to have a language designed from the ground-up to obsess over bytes for WASM. Trying to do that with a familiar high-level language with a rich standard library is tricky.
you can just compile c/c++ to wasm in the browser - there are wasi/emscripten builds of clang itself around (yosys, clang-repl, etc).
Yes, those are fascinating technologies. But way too big to be running in a small app in the browser.
> compiles to wasm in less than 1Mb of wasm
Janet, a Clojure-like Lisp compiles a whole playground of itself and the std lib in 823kb: https://janetdocs.org/playground
https://codeberg.org/veqq/janetdocs/src/branch/master/public...
you can do smaller for other things.
Janet, a Clojure-like Lisp compiles a whole playground of itself and the std lib in 823kb: https://janetdocs.org/playground
https://codeberg.org/veqq/janetdocs/src/branch/master/public...
you can do smaller for other things.
C based Mandelbrot WASM demos can be ~1 KB total. Assuming you mean a simple scripting language though, Assembly Script does exactly that.
AssemblyScript ships its own garbage collector and doesn't seem to making progress on supporting WASM GC.
AssemblyScript in general seems to have stopped making much progress. Unless you benefit greatly from having exact width numeric types it's very difficult to justify using it over normal TS.
Related: the uLisp assembler. It's small, elegant, and well-documented.
http://www.ulisp.com/show?2Z88
http://www.ulisp.com/show?2Z88
Also (on the bigger than this rather than smaller), Hoot, Spritely's Guile-on-Wasm project https://spritely.institute/hoot/
I really would like to see a small language that compiles to wasm in the browser.
Of course you can use things like Lua that has it's own vm also in wasm. Or Rhai with it's own interpreter. But I am looking for a language that compiles to wasm in less than 1Mb of wasm