Getting Started

Installation

using Pkg
Pkg.add(url="https://github.com/GroupTherapyOrg/WasmTarget.jl")

Requirements:

• Julia 1.12 (required — IR format is version-specific)
• Node.js 22+ or a WasmGC-capable browser (Chrome 119+, Firefox 120+)

Optional:

• Binaryen (wasm-opt) for optimization
• wasm-tools for validation

First Compilation

using WasmTarget

add(a::Int32, b::Int32)::Int32 = a + b
bytes = compile(add, (Int32, Int32))
write("add.wasm", bytes)

node -e '
  const fs = require("fs");
  WebAssembly.instantiate(fs.readFileSync("add.wasm"))
    .then(m => console.log(m.instance.exports.add(3, 7)));
'
# => 10

Multiple Functions

square(x::Float64)::Float64 = x * x
cube(x::Float64)::Float64 = x * square(x)

bytes = compile_multi([
    (square, (Float64,)),
    (cube,   (Float64,)),
])

Both are exported. cube calls square inside the module.

Optimization

bytes = compile(sin, (Float64,); optimize=true)

Requires wasm-opt installed. Typical size reduction is 80-90%.