a301202b7d
When `Linker` was first created it was attempted to be created with the ability to instantiate any wasm modules, including those with duplicate import strings of different types. In an effort to support this a `Linker` supports defining the same names twice so long as they're defined with differently-typed values. This ended up causing wast testsuite failures module linking is enabled, however, because the wrong error message is returned. While it would be possible to fix this there's already the possibility for confusing error messages today due to the `Linker` trying to take on this type-level complexity. In a way this is yet-another type checker for wasm imports, but sort of a bad one because it only supports things like globals/functions, and otherwise you can only define one `Memory`, for example, with a particular name. This commit completely removes this feature from `Linker` to simplify the implementation and make error messages more straightforward. This means that any error message coming from a `Linker` is purely "this thing wasn't defined" rather than a hybrid of "maybe the types didn't match?". I think this also better aligns with the direction that we see conventional wasm modules going which is that duplicate imports are not ever present.
wasmtime
A standalone runtime for WebAssembly
A Bytecode Alliance project
Guide | Contributing | Website | Chat
Installation
The Wasmtime CLI can be installed on Linux and macOS with a small install script:
$ curl https://wasmtime.dev/install.sh -sSf | bash
Windows or otherwise interested users can download installers and binaries directly from the GitHub Releases page.
Example
If you've got the Rust compiler installed then you can take some Rust source code:
fn main() {
println!("Hello, world!");
}
and compile/run it with:
$ rustup target add wasm32-wasi
$ rustc hello.rs --target wasm32-wasi
$ wasmtime hello.wasm
Hello, world!
Features
-
Lightweight. Wasmtime is a standalone runtime for WebAssembly that scales with your needs. It fits on tiny chips as well as makes use of huge servers. Wasmtime can be embedded into almost any application too.
-
Fast. Wasmtime is built on the optimizing Cranelift code generator to quickly generate high-quality machine code at runtime.
-
Configurable. Whether you need to precompile your wasm ahead of time, generate code blazingly fast with Lightbeam, or interpret it at runtime, Wasmtime has you covered for all your wasm-executing needs.
-
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:
- Rust - the
wasmtimecrate - C - the
wasm.h,wasi.h, andwasmtime.hheaders - Python - the
wasmtimePyPI package - .NET - the
WasmtimeNuGet package - Go - the
wasmtime-gorepository
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.