Shopify + Postmark integration

Plandalf does not read your Shopify orders and has no native Postmark step. Plandalf sends receipts and emails itself, and it can also call Postmark's Email API with Send Webhook or Zapier. A Plandalf offer opened from a Shopify page can then email the buyer from your own Postmark server.

1. Put the offer on the Shopify page

   Add the Plandalf SDK script before the closing body tag of theme.liquid and a button with data-plandalf-present on the right template. Leave the native add-to-cart button doing its own job.

2. Get a Postmark server token

   Postmark's Email API reference says requests carry an X-Postmark-Server-Token header, a server-level token from the API Tokens tab of the server. Postmark also says the From address must be a registered, confirmed sender signature.

3. Start a sequence on Checkout Completed

   In Plandalf open Automation, then My Sequences, choose Plandalf and Checkout Completed, and pick the offer. Use the Test tab to select a recent checkout so the variable menu fills.

4. Add Send Webhook for Postmark

   Add Plandalf, Send Webhook, POST, to https://api.postmarkapp.com/email. In Headers add the server token header and an Accept of application/json. Plandalf sends application/json as the Content-Type when you leave it blank.

5. Write the message

   Build a payload with From as your signature address, To as {{trigger.customer_email}}, and an HTML or text body that mentions {{trigger.line_items_summary}}. For stored templates, read Postmark's Templates section for the template send call and its fields.

6. Test and check the result

   Switch on Run on test purchases, buy through the test link with your own email, and open the run in the Events view. Postmark's batch endpoint returns 200 even when single messages fail, so if you ever use it, read each message's result.

• Plandalf has its own Send Email and Send Order Receipt steps. Use Postmark only when the message must leave from your Postmark server or use a template stored there.
• Postmark is a sending service, not an audience. Nothing here adds the buyer to a list or tags them, so pair it with an email platform if you need that.
• The Postmark server token sits in the step's headers. Plandalf does not sign Send Webhook requests, so limit the token to the one server you send from.
• Postmark's reference describes an optional MessageStream field, with the default outbound stream used when it is omitted. Choose the stream that matches the kind of message you send.
• Plandalf waits up to 30 seconds for a reply and its docs say not to assume automatic retries, so read the step result before relying on a Postmark email for something like a download link.

Does Shopify integrate with Postmark?

Plandalf cannot tell you what Shopify and Postmark do with each other, so check Postmark's own integrations list for that. Between Plandalf and Postmark there is no native step, and the connection is a Send Webhook call to Postmark's Email API.

How do I send Plandalf emails through Postmark?

Build a sequence on Checkout Completed with a Send Webhook step that posts to Postmark's send endpoint with your server token in the headers. The recipe above lists the fields.

Shopify Postmark integration: can Plandalf send my Shopify order emails?

No. Plandalf does not read Shopify orders. It emails only the buyers of offers that were paid through Plandalf.

Do I need Postmark if Plandalf already sends receipts?

No. Send Order Receipt and Send Email work without Postmark. Postmark is useful when you want mail sent from your own Postmark server or built from its templates.

Checked October 26, 2026 against Plandalf's own setup guides and the vendor documentation: Postmark developer docs: Email API.