Pros of Wasmer

• Supports multiple backends (LLVM, Cranelift, Singlepass)
• More extensive language support (Python, PHP, Ruby, etc.)
• Active development and larger community

Cons of Wasmer

• Generally slower execution compared to Lucet
• Higher memory usage for runtime and compiled modules
• More complex setup and configuration

Code Comparison

Wasmer:

use wasmer::{Store, Module, Instance};

let module = Module::from_file(&store, "example.wasm")?;
let instance = Instance::new(&module, &imports)?;
let result = instance.exports.get_function("sum")?;

Lucet:

use lucet_runtime::{DlModule, Limits, Region};

let module = DlModule::load("example.so")?;
let region = Region::create(1, &Limits::default())?;
let instance = region.new_instance(module)?;
let result = instance.run("sum", &[])?;

Both Wasmer and Lucet provide WebAssembly runtimes, but they have different focuses and trade-offs. Wasmer aims for broader language and platform support, while Lucet prioritizes performance and security for server-side applications. The code examples demonstrate the slightly different approaches to loading and executing WebAssembly modules in each runtime.

Pros of WAVM

• Supports a wider range of WebAssembly features, including SIMD and threading
• Generally faster execution speed for complex WebAssembly modules
• More actively maintained with frequent updates and improvements

Cons of WAVM

• Larger runtime footprint and longer compilation times
• Less focus on sandboxing and security features
• More complex setup and integration process

Code Comparison

WAVM example:

#include "WAVM/Runtime/Runtime.h"
#include "WAVM/IR/Module.h"

WAVM::Runtime::ModuleRef compileModule(const std::vector<U8>& wasmBytes)
{
    return WAVM::Runtime::compileModule(wasmBytes);
}

Lucet example:

use lucet_runtime::{DlModule, Limits, MmapRegion, Region};

let region = MmapRegion::create(1, &Limits::default()).unwrap();
let module = DlModule::load("path/to/module.so").unwrap();
let instance = region.new_instance(module).unwrap();

Both WAVM and Lucet provide WebAssembly runtime environments, but they have different focuses and trade-offs. WAVM offers broader WebAssembly support and potentially faster execution for complex modules, while Lucet emphasizes sandboxing, security, and faster startup times. The choice between them depends on specific project requirements and priorities.

Pros of wasmi

• Written in pure Rust, offering better portability and integration with Rust projects
• Supports a wider range of WebAssembly features, including more recent proposals
• Easier to use and integrate as an interpreter, with a simpler API

Cons of wasmi

• Generally slower execution compared to Lucet's AOT compilation approach
• Higher memory usage during runtime due to interpretation overhead
• Less optimized for production environments with high-performance requirements

Code Comparison

wasmi example:

let module = Module::from_buffer(&wasm_binary)?;
let instance = ModuleInstance::new(&module, &ImportsBuilder::default())?;
let result = instance.invoke_export("add", &[RuntimeValue::I32(1), RuntimeValue::I32(2)], &mut NopExternals)?;

Lucet example:

let module = lucet_runtime::Module::load(&path)?;
let region = MmapRegion::create(1, &Limits::default())?;
let instance = region.new_instance(module)?;
let result = instance.run("add", &[1_i32.into(), 2_i32.into()])?;

Pros of wasm3

• Highly portable, runs on a wide range of platforms including microcontrollers
• Lightweight and fast interpreter, suitable for embedded systems
• Easy to integrate into existing projects

Cons of wasm3

• Interpreter-based, generally slower than AOT compilation
• Limited optimization capabilities compared to Lucet's AOT approach
• May not be suitable for high-performance server-side applications

Code Comparison

wasm3:

m3_env env = m3_NewEnvironment ();
m3_runtime runtime = m3_NewRuntime (env, 64*1024, NULL);
m3_module module;
m3_LinkRawFunction (module, "env", "print", "v(i)", &print);

Lucet:

let module = DlModule::load("my_module.so")?;
let region = MmapRegion::create(1, &Limits::default())?;
let instance = region.new_instance(module)?;
instance.run("main", &[])?;

Summary

wasm3 is a lightweight, portable WebAssembly interpreter suitable for embedded systems and easy integration. Lucet, on the other hand, is an AOT compiler focused on high-performance server-side applications. wasm3 offers broader platform support but may sacrifice performance, while Lucet provides better optimization and speed but with more limited portability.