shuttle-engine

This crate contains the core runtime of the Shuttle concurrency testing tool. It provides the building blocks for creating functionality on top of Shuttle: the execution engine, the Scheduler trait, and the primitives that schedulers and std replacements are built from. Reach for it when you want to build something new atop the runtime, such as a custom scheduler or a Shuttle-compatible version of a concurrency primitive.

Contents

This crate holds the machinery that executes and controls a Shuttle test:

• runtime — the execution engine: tasks, threads (built on corosensei continuations), thread-local storage, vector clocks, and failure reporting.
• scheduler — the Scheduler trait that every scheduler implements, along with schedule serialization, metrics, and the data-source traits used to control nondeterministic values. The built-in schedulers themselves live in shuttle-schedulers.
• config — Config and the associated knobs (MaxSteps, FailurePersistence, UngracefulShutdownConfig, ...).
• future — the async primitives underpinning Shuttle's executor, including BatchSemaphore.
• current, hint, sync_types, thread_support — the supporting APIs that shuttle-std builds its std mirrors on top of.

Features

• vector-clocks — track causality between tasks. Required for the current clock APIs.
• annotation — emit annotated schedules for the Shuttle Explorer extension.

Stability

This crate exposes considerably more of Shuttle's internals than the shuttle crate does, and that surface evolves alongside the runtime. Expect it to change more freely than a typical crate's public API, and pin a version if you build against it.