Events & Triggers

Inngest functions are triggered asynchronously by events coming from various sources, including:

Your application: Send an event from your application’s backend with the Inngest SDK.

Cron schedule: Run an Inngest function periodically with a trigger using cron syntax.

Webhook events: Use Inngest as a webhook consumer for any service to trigger functions.

Another Inngest function: Directly invoke other functions to compose more powerful functions.

You can also launch a specific function as fire-and-forget background work from inside another run with deferred functions.

You can customize each of these triggers in multiple ways:

• Filtering event triggers - Trigger a function for a subset of matching events sent.
• Delaying execution - Trigger a function to run at a specific timestamp in the future.
• Batching events - Process multiple events in a single function for more efficient systems.
• Multiple triggers - Use a single function to handle multiple event types.

Why events?

Using Events to trigger Inngest Functions instead of direct invocations offers a lot of flexibility:

• Events can trigger multiple Inngest Functions.
• Events can be used to synchronize Inngest Function runs with cancellation and “wait for event” step.
• Events can be leveraged to trigger Functions across multiple applications.
• Similar Events can be grouped together for faster processing.

Events act as a convenient mapping between your application actions (ex, user.signup) and your application's code (ex, sendWelcomeEmail() and importContacts()):

Learn more about Events

Blog post: How event Filtering works: Accidentally Quadratic: Evaluating trillions of event matches in real-time

Blog post: Events in practice: Building an Event Driven Video Processing Workflow with Next.js, tRPC, and Inngest