---
title: "What is Trigger.dev?"
sidebarTitle: "What is Trigger.dev?"
---

Trigger.dev is a platform, SDK and API for building and running Jobs in your codebase, triggered by various sources, but without having to worry about managing any complicated orchestration infrastructure.

It can be used from _any_ Node.js (support versions) or TypeScript backend application (including serverless applications and microservices).

## What we take care of for you:

- We make it possible to run long-running Jobs on serverless platforms that have short timeouts (e.g. 30 seconds).
- We provide an SDK for building Jobs in your codebase, triggered by various sources such as [events](/documentation/concepts/triggers/events), [scheduled events](/documentation/concepts/triggers/scheduled), and [webhooks](/documentation/concepts/triggers/webhooks).
- We provide an orchestration platform for running Jobs in your codebase.
- We provide out-of-the-box Integrations with popular services such as [Slack](/integrations/apis/slack), [OpenAI](/integrations/apis/openai), [GitHub](/integrations/apis/github) and [more](/integrations), which vastly simplifies the process interacting with 3rd-party services.
  - We handle OAuth for you
- We provide a nice UI for viewing and debugging your Jobs.

## What you take care of:

- You write your Jobs in your codebase.
- You get a Trigger.dev API Key and add it to your codebase.
- You deploy your codebase.

## How it works

To get an idea of how Trigger.dev works, let's take a look at a simple Job that sends a Slack message when a GitHub issue is labelled as `critical`:

```ts
import { Job } from "@trigger.dev/sdk";
import { Github, events } from "@trigger.dev/github";
import { Slack } from "@trigger.dev/slack";

//GitHub integration with API Key (it supports OAuth too)
const github = new Github({
  id: "github",
  token: process.env.GITHUB_API_KEY!,
});

//Slack integration with OAuth
const slack = new Slack({
  id: "slack",
});

client.defineJob({
  id: "critical-issue-alert",
  name: "Critical Issue Alert",
  version: "0.1.0",
  //When a GitHub issue is modified on the triggerdotdev/trigger.dev repo
  trigger: github.triggers.repo({
    event: events.onIssue,
    owner: "triggerdotdev",
    repo: "trigger.dev",
  }),
  //include any integrations you want to use
  integrations: {
    slack,
  },
  //this function gets executed when the trigger fires
  run: async (payload, io, ctx) => {
    await io.logger.info(`Action was ${payload.action}`);

    if (payload.action === "labeled" && payload.label?.name === "critical") {
      //use the Slack integration to post a message
      await io.slack.postMessage("post message", {
        channel: "C04GWUTDC3W",
        text: `Issue ${payload.issue.number}: ${payload.issue.title} is critical!`,
      });
    }
  },
});
```

This code lives in a file inside your project repo.

It is listening for the [issueEvent](/integrations/apis/github-triggers#onissue) GitHub webhook, and when it receives one, we will take care of calling the `run` function supplied to the `Job` constructor with the webhook payload. This gives you the following advantages over traditional webhooks:

- We will automatically register the webhook with GitHub for you, and verify the payload signature.
- We provide a nicely typed `event` payload to your `run` function, so you don't have to setup webhook payload types.
- If your server isn't running, we will wait until it's back online before attempting to run the Job.
- It is very easy to test your Job locally using our [Test Run](/documentation/guides/testing-jobs) feature.

As you can see the above Job also makes a call to our Slack [postMessage](/integrations/apis/slack) function, which provides the following advantages over using the raw Slack API:

- We automatically handle the OAuth flow for you, so you don't have to worry about setting up a Slack app and dealing with credentials in your code (see our [Authentication](/documentation/concepts/integrations#authentication) guide for more details).
- We will automatically retry the request if the Slack API returns an error.
- We provide a nicely typed `response` object from your `postMessage` function, so you don't have to setup Slack API types.

## Why use Trigger.dev?

Apart from the reasons mentioned above, there are a few other reasons why you might want to use Trigger.dev:

- You want to access your database or other internal services from your Jobs, without having to expose them to the internet.
- You want to colocate your Jobs with your code, so you can deploy them together in one atomic unit.
- You want to build event-driven architectures without having to manage any complicated orchestration infrastructure.
- You want to add in delays or retries to your Jobs, without having to worry about managing a queue.

## Architecture

Below is a simplified architecture diagram of how Trigger.dev works:

{/* https://www.tldraw.com/r/v2_KEeyTalIH0NRKdsb01Lqt?viewport=36%2C-165%2C2234%2C1420&page=page%3AOecar06rEOb6Kpu9XzDKo */}
![Architecture](/images/architecture.png)

As you can see above, we communicate between your code and the Trigger.dev platform. This allows us to send events to your code, and receive tasks from your code.

## Limitations

There are a few limitations that are important to understand.

In the latest version the following are not supported:

### Long-running servers

Currently Trigger.dev is optimized for deployment to serverless functions, but not for long-running servers.

This limitation will be removed in the future by adding an alternative mode so Jobs works well on localhost and long-running servers.

### Compute intensive tasks

Because Trigger.dev is optimized for serverless functions, it is not well suited for compute intensive jobs as each individual task is limited to the [Maximum Run Chunk Execution Duration](/placeholder)
