Before building your Zap, set up your store in LemonInk once.

1. Go to the Stores section, add a new store and pick the "Custom" integration. Its page shows a store ID and an API key — we generate the key for you automatically, no need to create one by hand.
2. In Your files, link each ebook product from your shop to the corresponding master file. Use the same product ID that your store sends when it notifies Zapier about new orders.
3. Only link the products that need to be watermarked — LemonInk automatically skips any line item it doesn't recognise.
4. Optionally, enable email delivery on the store so LemonInk sends the download link to your customers for you.

Now for the good part: send the whole order to LemonInk and let us figure out the rest.

Add a "LemonInk" action and select the "Create Order" event. When Zapier asks you to connect your LemonInk account, paste the API key from your store's page (step one). Then map the fields from your store notification:

1. Store ID — the ID you copied from the Stores section.
2. External ID — the unique order ID from your store. We use it to avoid watermarking the same order twice, so it must be unique.
3. Order number (optional) — the human-friendly reference shown to your customer.
4. Customer — the buyer's email and name (or first and last name). Email is required if you want LemonInk to deliver the download link automatically.
5. Line items — the product IDs from the order. LemonInk matches them against the products you linked in the previous step and watermarks only the ones it recognises.

Because the mapping lives in LemonInk, there's no need to loop over line items, build a lookup table or filter out non-ebook orders in Zapier — just pass the order through.