Core Concepts

Before diving deeper into Stepflow, it's helpful to understand the key concepts that make up the system.

Workflows

A workflow is a durable function that orchestrates a series of steps. Workflows are:

• Durable: State is persisted, so workflows survive restarts
• Resumable: If a workflow fails, it resumes from the last successful step
• Type-safe: Full TypeScript support with inferred types

const workflow = createWorkflow(
  { id: "my-workflow" },
  async ({ step, sleep }) => {
    // Workflow logic here
  },
);

Steps

A step is an atomic unit of work within a workflow. Steps are:

• Checkpointed: Results are saved, so steps never re-execute on retry
• Idempotent: Safe to retry without side effects
• Named: Each step has a unique name for tracking

const result = await step.run("process-order", async () => {
  return await processOrder(orderId);
});

Durable Sleep

Unlike regular setTimeout, Stepflow's sleep is durable:

• Survives process restarts
• Can span days, weeks, or months
• Workflow resumes exactly when the sleep ends

await sleep("wait-3-days", "3d");

Events

Workflows can wait for external events with optional timeouts:

const payment = await waitForEvent("payment-received", {
  timeout: "1h",
});

Events are sent from outside the workflow:

await stepflow.notify(eventId, { status: "paid" });

Storage Adapters

Stepflow uses pluggable storage to persist workflow state:

Framework Adapters

Framework adapters expose Stepflow as HTTP endpoints:

• Trigger workflows via REST API
• Stream real-time updates via SSE
• Integrate with any web framework

Client SDKs

Client SDKs make it easy to interact with Stepflow from your frontend:

• TypeScript client for any environment
• React hooks for web apps
• React Native hooks for mobile apps

Execution Model

When a workflow runs:

1. Trigger: Workflow is triggered with input data
2. Execute: Steps run sequentially (or in parallel)
3. Checkpoint: Each step result is saved
4. Sleep/Wait: Workflow pauses for sleeps or events
5. Resume: Workflow continues from where it left off
6. Complete: Final result is returned

Trigger → Step 1 → Step 2 → Sleep → Step 3 → Complete
                              ↓
                         (persisted)
                              ↓
                    Process restarts...
                              ↓
                         Resume → Step 3 → Complete

Next Steps

• Workflows - Deep dive into workflow definitions
• Steps - Learn about step execution
• Storage - Choose a storage adapter