Wasmer-JS

Wasmer-JS is a mono-repo of multiple JavaScript packages enabling easy use of WebAssembly Modules in Node and the Browser.

• @wasmer/wasi - WebAssembly WASI implementation for Node and browsers.

• @wasmer/cli - WebAssembly WASI CLI for Node.js (wasmer-js)

• @wasmer/wasmfs - WASI/Wasm FileSystem.

• @wasmer/io-devices - Implementation Support for the Wasmer Experimental I/O Devices for Wassmer-JS.

• @wasmer/wasm-transformer - the JS interface for the wasm_transformer crate

• @wasmer/wasm-terminal - A browser terminal/shell for interacting with WASI/Wasm Modules. It powers WebAssembly.sh.

Documentation

Documentation for the Wasmer-JS Stack, can be found on the Wasmer Docs.

Development

Contributing into Wasmer-JS it's very easy, just clone the repo and run:

npm install

NOTE: This will run lerna bootstrap, and bootstrap the JS Packages.

To start development mode, you can run the dev command:

npm run dev

This will serve the examples/wasm-shell example, which can be accessed with: http://localhost:1234/

Building the project

To build all the packages in the project, you can run the build command:

npm run build

This will bundle JS Packages into ./dist directory.

Tests

To make changes to any of the sub projects, they can be tested by either: Running their local tests with npm run test in their respective package directory, or running it the root:

npm run test

Contributing

For additional contribution guidelines, please see our CONTRIBUTING.md and our Code of Conduct.

Using Lerna

Please see the website for lerna for a quick introduction into what it is. Here are some general notes about using lerna in this project:

• Packages can be added by simply creating a new directory within the packages/ directory, and running npm init in this new package directory. Then, the new package must be botstraped using learna. For this project, this can be done running npm run lerna:bootstrap in the base project directory.

• To add new dependencies and keep build times low, devDependencies (not CLI dependencies) must be added to the root package.json file. Project installation / runtime dependencies are managed for each package individually.

• Sibling JS packages can depend on one another. You can do this by using @lerna/add. For example, lerna add @wasmer/package-1 --scope=@wasmer/package-2 will add @wasmer/package-1@^1.0.0 to @wasmer/package-2. However, there are issues when a published package tries to depend on a new unpublished package, please see this issue for the discussion. And, one should not be afraid of learna link convert, as file:// dependencies will be automatically converted by lerna on publish, for example see here.