Installation

To install this Cargo subcommand, first you'll want to install Rust and then you'll execute:

$ cargo install cargo-wasi

After that you can verify it works via:

$ cargo wasi --version

Read more about installation

Usage

The cargo wasi subcommand is a thin wrapper around cargo subcommands, providing optimized defaults for the wasm32-wasi target. Because of this usage of cargo wasi looks very similar to Cargo itself:

• cargo wasi build - build your code in debug mode for the wasi target.
• cargo wasi build --release - build the optimized version of your *.wasm.
• cargo wasi run - execute a binary
• cargo wasi test - run your tests in wasm32-wasi
• cargo wasi bench - run your benchmarks in wasm32-wasi

And that's just a taste! In general if you'd otherwise execute cargo foo --flag you can likely execute cargo wasi foo --flag and everything will "just work" for the wasi target. For more long-form documentation, examples, and more explanation, be sure to consult the book documentation for this subcommand as well.

To give it a spin yourself, try out the hello-world versions of programs!

$ cargo new wasi-hello-world
     Created binary (application) `wasi-hello-world` package
$ cd wasi-hello-world
$ cargo wasi run
   Compiling wasi-hello-world v0.1.0 (/code/wasi-hello-world)
    Finished dev [unoptimized + debuginfo] target(s) in 0.15s
     Running `cargo-wasi target/wasm32-wasi/debug/wasi-hello-world.wasm`
     Running `target/wasm32-wasi/debug/wasi-hello-world.wasm`
Hello, world!

or a library with some tests:

$ cargo new wasi-hello-world --lib
     Created library `wasi-hello-world` package
$ cd wasi-hello-world
$ cargo wasi test
   Compiling wasi-hello-world v0.1.0 (/code/wasi-hello-world)
    Finished dev [unoptimized + debuginfo] target(s) in 0.19s
     Running target/wasm32-wasi/debug/deps/wasi_hello_world-9aa88657c21196a1.wasm
     Running `/code/wasi-hello-world/target/wasm32-wasi/debug/deps/wasi_hello_world-9aa88657c21196a1.wasm`

running 1 test
test tests::it_works ... ok

test result: ok. 1 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out

Configuration

The cargo wasi subcommand takes no flags itself since it forwards all flags to Cargo itself. To configure cargo wasi you'll be editing your workspace Cargo.toml:

[package.metadata]
wasm-opt = false              # force wasm-opt to never run
wasm-name-section = false     # remove the name section from release artifacts
# ...

For a full list of configuration options see the documentation.

Updating cargo-wasi

If you already have cargo-wasi installed and you'd like to update your installation, you can execute:

$ cargo install cargo-wasi --force

Uninstalling cargo-wasi

If you'd like to remove cargo-wasi from your system, you'll want to first clear out the subcommand's caches and then remove the subcommand itself.

$ cargo wasi self clean
$ cargo uninstall cargo-wasi

License

This project is licensed under either of

• Apache License, Version 2.0, (LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0)
• MIT license (LICENSE-MIT or http://opensource.org/licenses/MIT)

at your option.

Contribution

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in this project by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.