Wasmtime is a WebAssembly runtime and sandboxed bytecode executor designed to run WebAssembly bytecode on a host system. It functions as an embeddable engine that integrates into applications through native APIs and language-specific bindings, as well as a standalone execution environment accessible via a command line interface. It is a WASI compatible runtime, implementing the WebAssembly System Interface to provide portable access to system resources.
The engine utilizes a JIT compilation model to translate intermediate representation into optimized machine code for various CPU architectures. To balance performance and startup time, it supports multiple execution strategies, including a single-pass baseline compiler for fast startup and a portable interpreter for immediate execution without compilation.
The runtime provides secure code sandboxing and resource consumption limits for CPU and memory to ensure host stability. Security is further managed through bounds-checked memory access to mitigate side-channel attacks. Additionally, the project supports polyglot component integration, allowing software components written in different programming languages to communicate via standardized binary formats and interfaces.
