Struct CompiledModule 

pub struct CompiledModule { /* private fields */ }

The pre-compiled QuickJS WASM module.

Created once, reused across executions. Thread-safe. Each execution instantiates a fresh WASM instance from this module.

Implementations

impl CompiledModule

pub fn new() -> Result<Self>

Compile the embedded QuickJS WASM binary.

This is the expensive operation (~10-50ms). Do it once at startup. For repeated runs, use load_cached() with a serialized module.

Errors

Returns an error if the WASM fails to compile or instantiate.

pub fn serialize(&self) -> Result<Vec<u8>>

Serialize the compiled module to bytes for caching.

Save the result to disk. On next startup, use load_cached() to skip compilation (~50ms → ~1ms).

Errors

Returns an error if the underlying module serialization fails.

pub fn load_cached(bytes: &[u8]) -> Result<Self>

Load a pre-compiled module from serialized bytes.

Safety

The serialized bytes must have been produced by serialize() from the same wasmtime version. Loading tampered bytes is memory-safe (wasmtime validates) but may produce unexpected behavior.

Errors

Returns an error if the engine or module deserialization fails.

pub fn new_cached(cache_path: &Path) -> Result<Self>

Compile and cache to disk. On next call, loads from cache.

The cache file carries an 8-byte integrity tag so that trivially tampered files are rejected before reaching the unsafe deserialize path. On Unix, the file is created with mode 0o600.

Errors

Returns an error if compilation fails.

pub fn engine(&self) -> &Engine

Get a reference to the wasmtime Engine.

pub fn module_ref(&self) -> &Module

Get a reference to the compiled WASM Module.

pub fn execute( &self, scripts: &[String], bridge: Arc<dyn Bridge>, config: &SandboxConfig, ) -> Result<ExecutionResult>

Execute JavaScript in a fresh sandboxed instance.

Each call creates a new WASM instance with isolated memory. No state leaks between executions.

Errors

Returns an error if WASM execution traps or resources are exhausted.

pub fn execute_in_context( &self, scripts: &[String], bridge: Arc<dyn Bridge>, config: &SandboxConfig, context_id: &ContextId, message_bus: Option<&Mutex<MessageBus>>, ) -> Result<ExecutionResult>

Execute in a named context with access to the message bus.

Errors

Returns an error if WASM execution traps or resources are exhausted.

pub fn snapshot_memory(store: &Store<HostState>, memory: &Memory) -> Vec<u8>

Snapshot the WASM linear memory for state save/restore.

Returns a byte vector that can be restored later. Cost: ~1μs for a 4MB instance (just memcpy).

pub fn restore_memory( store: &mut Store<HostState>, memory: &Memory, snapshot: &[u8], )

Restore WASM linear memory from a snapshot.