By default, ShipThing uses Vercel’s cron jobs feature to trigger Next.js serverless functions on a schedule. However, you can replace this setup with the background job service of your choosing, such as trigger.dev or BetterStack.

​
Writing functions

Next.js serverless functions act as the basis for scheduled jobs. You can write them in any runtime and trigger them using a simple HTTP call. To demonstrate, we’ve created a example endpoint called keep-alive that creates, then subsequently deletes, a temporary page object in the database. This is a little workaround to prevent databases going to sleep after a period of inactivity. You should probably remove this if you don’t need it. Additionally, while you can add cron jobs to any app, we use the api app to keep our background jobs, webhooks and other such tasks isolated from our UI. You can add new functions by creating the relevant route.ts files in the apps/api/app/cron folder. While you can put them anywhere, we use the aptly named cron folder to hold our endpoints designed to run as cron jobs. For example:
apps/api/app/cron/[your-function]/route.ts
import { database } from '@repo/database';

// Must use GET for Vercel cron jobs
export const GET = async () => {
  // Do stuff

  return new Response('OK', { status: 200 });
};

​
Scheduling functions

After you write your serverless function, you can schedule it by amending the vercel.json file in the API app. To serve as an example, we’ve wired up the keep-alive job mentioned above to run every 10 minutes.
apps/api/vercel.json
{
  "crons": [
    {
      "path": "/cron/keep-alive",
      "schedule": "0 1 * * *"
    }
  ]
}

​
How Vercel triggers cron jobs

To trigger a cron job, Vercel makes an HTTP GET request to your project’s production deployment URL, using the path provided in your project’s vercel.json file. For example, Vercel might make a request to: 
https://*.vercel.app/cron/keep-alive

​
Triggering functions manually

Should you need to trigger a cron job manually, you can either do so in the Vercel dashboard or just hit the endpoint with a standard HTTP request. For example:
Terminal
curl -X GET http://localhost:3002/cron/keep-alive