Blazen Core

The workflow engine at the heart of the Blazen framework.

This crate provides:

• [Context] -- shared, typed key/value state accessible by all steps.
• [StepFn] / [StepOutput] / [StepRegistration] -- step definition primitives.
• [WorkflowBuilder] / [Workflow] -- fluent construction and execution of event-driven workflows.
• [WorkflowHandler] -- handle for awaiting results and streaming intermediate events.
• [WorkflowError] -- comprehensive error type for everything that can go wrong during workflow execution.

Architecture

A workflow is a directed graph of steps. Each step declares which event types it accepts and what it may emit. The runtime maintains an internal event queue; when an event arrives, the engine looks up matching step handlers and spawns them concurrently. Step outputs are fed back into the queue until a StopEvent terminates the loop.