Extending with Hooks

PocketBase hooks let you run custom JavaScript on the server — right inside your instance. Add API routes, react to record changes, schedule cron jobs, or send emails, all without deploying a separate backend.

On PocketBase Cloud you write and manage hooks directly in the dashboard: open your instance and go to the Hooks tab.

Creating a hook

Open your PocketBase instance in the dashboard
Go to the Hooks tab
Click New Hook, give the file a name ending in .pb.js (e.g., main.pb.js)
Write your code and save — the instance reloads hooks automatically

Example: a custom API route

routerAdd("GET", "/api/hello/{name}", (e) => {
  const name = e.request.pathValue("name");
  return e.json(200, { message: `Hello ${name}!` });
});

Your route is immediately available at https://<instance-name>.pocketbasecloud.com/api/hello/world.

Example: react to record changes

Run logic whenever a record is created, updated, or deleted:

onRecordCreate((e) => {
  // runs before the record is persisted — you can still modify it
  e.record.set("slug", e.record.get("title").toLowerCase().replaceAll(" ", "-"));
  e.next();
}, "posts");

onRecordAfterCreateSuccess((e) => {
  // runs after the record is saved
  console.log("new post:", e.record.id);
  e.next();
}, "posts");

Example: scheduled cron jobs

cronAdd("cleanup", "0 3 * * *", () => {
  const records = $app.findRecordsByFilter(
    "sessions",
    "created < @yesterday",
    "-created",
    200,
    0
  );
  for (const record of records) {
    $app.delete(record);
  }
});

Example: send an email

onRecordAfterCreateSuccess((e) => {
  const message = new MailerMessage({
    from: { address: e.app.settings().meta.senderAddress },
    to: [{ address: e.record.email() }],
    subject: "Welcome!",
    html: "<p>Thanks for signing up.</p>",
  });
  e.app.newMailClient().send(message);
  e.next();
}, "users");

What hooks can access

Hooks run in PocketBase’s embedded JavaScript VM with access to:

$app — the full PocketBase app instance (query, create, update records)
routerAdd — register custom HTTP routes
onRecord* event handlers — before/after create, update, delete
cronAdd — cron-style scheduled jobs
$http.send() — make outbound HTTP requests to third-party APIs
$os, $filesystem, $security — utility namespaces

See the PocketBase JSVM documentation for the complete API.

When to use a backend instead

Hooks are perfect for lightweight logic tied to your data. For heavier workloads — long-running jobs, large dependencies, websockets, or code you want to develop and test locally as a normal project — deploy a dedicated backend alongside your instance.