Installation
The Wasmtime CLI can be installed on Linux and macOS (locally) with a small install
script:
curl https://wasmtime.dev/install.sh -sSf | bash
This script installs into $WASMTIME_HOME (defaults to $HOME/.wasmtime), and executable is placed in $WASMTIME_HOME/bin.
After running the install script above, follow the on-screen instructions.
Windows or otherwise interested users can download installers and
binaries directly from the GitHub
Releases page.
For additional installation options, refer to the online book CLI installation page.
Documentation on Wasmtime's currently supported versions can be found in the
online book
documentation.
Example
If you've got the Rust compiler
installed then you can take some Rust
source code:
fn main() {
println!("Hello, world!");
}
and compile it into a WebAssembly component with:
rustup target add wasm32-wasip2
rustc hello.rs --target wasm32-wasip2
Once compiled, you can run your component:
wasmtime hello.wasm
You should see the following output:
Hello, world!
(Note: make sure you installed Rust using the rustup method in the official
instructions above, and do not have a copy of the Rust toolchain installed on
your system in some other way as well (e.g. the system package manager). Otherwise, the rustup target add...
command may not install the target for the correct copy of Rust.)
Features
Fast. Wasmtime is built on the optimizing Cranelift code generator to
quickly generate high-quality machine code either at runtime or
ahead-of-time. Wasmtime is optimized for efficient instantiation, low-overhead
calls between the embedder and wasm, and scalability of concurrent instances.
Secure. Wasmtime's development is strongly focused on correctness and
security. Building on top of Rust's runtime safety guarantees, each Wasmtime
feature goes through careful review and consideration via an RFC
process. Once features are designed and implemented, they undergo 24/7
fuzzing donated by Google's OSS Fuzz. As features stabilize they become part
of a release, and when things go wrong we have a
well-defined security policy in place to quickly mitigate and patch any
issues. We follow best practices for defense-in-depth and integrate
protections and mitigations for issues like Spectre. Finally, we're working to
push the state-of-the-art by collaborating with academic researchers to
formally verify critical parts of Wasmtime and Cranelift.
Configurable. Wasmtime uses sensible defaults, but can also be
configured to provide more fine-grained control over things like CPU and
memory consumption. Whether you want to run Wasmtime in a tiny environment or
on massive servers with many concurrent instances, we've got you covered.
WASI. Wasmtime supports a rich set of APIs for interacting with the host
environment through the WASI standard.
Standards Compliant. Wasmtime passes the official WebAssembly test
suite, implements the official C
API of wasm, and implements
future proposals to WebAssembly as
well. Wasmtime developers are intimately engaged with the WebAssembly
standards process all along the way too.
Language Support
You can use Wasmtime from a variety of different languages through embeddings of
the implementation.
Languages supported by the Bytecode Alliance:
Languages supported by the community:
Documentation
📚 Read the Wasmtime guide here! 📚
The wasmtime guide is the best starting point to learn about what
Wasmtime can do for you or help answer your questions about Wasmtime. If you're
curious in contributing to Wasmtime, it can also help you do
that!
It's Wasmtime.
Wasmtime 是一个轻量级的 WebAssembly 运行时：它能快速且安全地执行 WebAssembly（wasm）程序。它用 Rust 编写，由 Bytecode Alliance（字节码联盟）主导开发。