There are two different runtimes available for Krustlet: wascc or wasi.
The wascc runtime is a secure WebAssembly host runtime, connecting "actors" and "capability
providers" together to connect your WebAssembly runtime to cloud-native services like message
brokers, databases, or other external services normally unavailable to the WebAssembly runtime.
The wasi runtime uses a project called wasmtime.
wasmtime is a standalone JIT-style host runtime for WebAssembly modules. It is focused primarily on
standards compliance with the WASM specification as it relates to WASI. If your
WebAssembly module complies with the WebAssembly
specification, wasmtime can run it.
It's important to note that the WASI standard and wasmtime are still under heavy development.
There are some key features (like networking) that are currently missing, but will be made available
in future updates.