Inngest is an event-driven durable execution platform that allows you to run fast, reliable code on any platform, without managing queues, infra, or state.

Write functions in TypeScript, Python or Go to power background and scheduled jobs, with steps built in.

Inngest handles the backend infra, queueing, scaling, concurrency, throttling, rate limiting, and observability for you.

The system is composed of the following services:

Event API - Receives events from SDKs via HTTP requests. Authenticates client requests via Event Keys. The Event API publishes event payloads to an internal event stream. Event stream - Acts as buffer between the Event API and the Runner. Runner - Consumes incoming events and performs several actions: Scheduling of new “function runs” (aka jobs) given the event type, creating initial run state in the State store database. Runs are added to queues given the function's flow control configuration. Resume functions paused via waitForEvent with matching expressions. Cancels running functions with matching cancelOn expressions Writes ingested events to a database for historical record and future replay. Queue - A multi-tenant aware, multi-tier queue designed for fairness and various flow control methods (concurrency, throttling, prioritization, debouncing, rate limiting) and batching. Executor - Responsible for executing functions, from initial execution, step execution, writing incremental function run state to the State store, and retries after failures. State store (database) - Persists data for pending and ongoing function runs. Data includes initial triggering event(s), step output and step errors. Database - Persists system data and history including Apps, Functions, Events, Function run results. API - GraphQL and REST APIs for programmatic access and management of system resources. Dashboard UI - The UI to manage apps, functions and view function run history. The source code for Inngest and all services is available on GitHub

https://www.inngest.com/docs/self-hosting