This is a simple online playground for wasm-tools parse and print, available at https://bytecodealliance.github.io/wasm-tools/parse / https://bytecodealliance.github.io/wasm-tools/print respectively.

In addition to cargo, you'll need to have node and cargo-component installed and on your path.

Then

npm ci

to install dependencies and

npm run build

to build.

Output will be placed under dist.

The ./component/wit/world.wit file defines the exported functions for use by the playground. After changing it you'll need to npm run build to regenerate the bindings file (the command will fail but still generate the bindings) and then implement the functions in ./component/src/lib.rs.

After npm run building again you can make use of those functions from ./src/worker.ts, with full type safety (thanks to jco).

It is also possible to use them outside of a worker, but since they run synchronously and block their thread the playground is designed to do all calls off the main thread.

To preview your changes after building you'll need to run a web server; the worker will not load from a file: URL. The simplest way to do this is by running npx http-server dist, but you can use whatever means you'd like.