Struct Engine 

pub struct Engine { /* private fields */ }

Shared wasmtime::Engine plus a background thread that ticks the epoch counter so per-store wall-clock deadlines can fire.

One Engine per process is enough; cloning a Plugin reuses the engine.

Implementations

impl Engine

pub fn new() -> Result<Self, EngineError>

Build an engine with no on-disk compilation cache. Every plugin is recompiled from scratch on load. Used by tests and the harness where a shared cache directory would add cross-run coupling.

pub fn with_cache(cache_dir: &Path) -> Result<Self, EngineError>

Build an engine backed by wasmtime’s on-disk compilation cache rooted at cache_dir. Compiling a plugin component (Plugin::load_*) is the dominant per-invocation cost — hundreds of milliseconds of Cranelift codegen for a multi-MB plugin — and it is pure: a function of the wasm bytes, the compiler config, and the wasmtime version. The cache keys on exactly those, so a second forge run (or a sibling process in a parallel regen) deserialises the prior artifact in single-digit milliseconds instead of recompiling.

Cache hits never change generated output: the cached entry is the same machine code Cranelift would have produced, and wasmtime’s own version/config fingerprint invalidates stale entries (a wasmtime bump simply misses and recompiles).

pub fn raw(&self) -> &WtEngine

Trait Implementations

impl Clone for Engine

fn clone(&self) -> Engine

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Engine

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.