Zaprite enables users to connect their own self-custody bitcoin wallets by providing an xPub. This allows users to remain in complete control of their own funds, while also enhancing onchain privacy by generating a new receiving address for each payment request.

You can use any software or hardware wallet that allows you to export an xPub. The following guide outlines the instructions for exporting your wallet xPub from a ColdCard, but the steps will be similar for most hardware wallets.

If you are not yet using a ColdCard hardware wallet, we highly recommended you check out their website over at coldcard.com.

We recommend always creating a new wallet/account for Zaprite. You should not use this wallet for any other external services as it will decrease your privacy and may affect financial reporting within Zaprite.

Create a ColdCard Wallet

If are connecting a new ColdCard that has not yet been used, then you can proceed to the next section.

If you would like to create a brand new wallet, you can do this by adding a Passphrase to your existing seed words. From the main menu, click Passphrase and follow the instructions provided.

More information about Passphrases can be found on ColdCard’s documentation website.

Export the Wallet xPub

Once you have your wallet loaded, the next step is to export the wallet’s Extended Public Key (xPub). From the main screen on your ColdCard, click through the following menu items:

Advanced > MicroSD Card > Export Wallet > Generic JSON

This will save a file called coldcard-export.json to the MicroSD card in the hardware wallet. Once you have saved the JSON file to your MicroSD Card, open the file on your computer to find the information you need to connect to Zaprite.

You will need to locate the wallet from the list of formats shown. In this example, we are using a Native SegWit wallet with addresses starting with bc1q. This can be found under the bip84 listing in the exported JSON file. We will use the xpub and first values from the bip84 data.

Connect your Wallet to Zaprite

The next step is to add your wallet to Zaprite. Navigate to the Connections screen and then click the Connect button under the Bitcoin card.

If you already have a Bitcoin wallet connected, you can click Settings, then click [ + New connection ] from the dropdown menu.

You will be prompted to enter some information about the wallet:

1. Wallet Provider: Choose ‘ColdCard’ from the options shown.
2. Label: Add a custom label to identify this wallet within Zaprite. This will not be visible to your Customers. Example: ‘ColdCard MK4’ or ‘ColdCard Q – Business’
3. Extended Public Key: Paste your xpub here. This will auto-generate the first receive address for the wallet in the Wallet Validation section at the bottom of the form.
4. Address Type: Choose the address type your wallet is using. In this example, we are using a SegWit (bc1q…) address format. You can change this setting if you have setup a Taproot wallet (bc1p…), or are adding an existing or older wallet (3…).

Once you have this information entered, the final step is to validate the wallet by confirming if Zaprite has generated the correct receiving address.

Wallet Validation

To validate the wallet connection you can use the first address shown in the same JSON export that you sourced the xpub above. Note the last 6 characters of the address and then return to Zaprite and enter those characters in the field provided.

You can also check this address by clicking through the Address Explorer menu on the main screen of your ColdCard.

Click OK to submit the wallet information. If the addresses match, your wallet will be successfully connected and available for use within Zaprite.

Wallet Settings

Once you have validated and connected your ColdCard wallet, Zaprite will generate and list the first 100 addresses for viewing.

This list shows which addresses have been Used, Reserved or Locked.

• Used: The address has received funds and will not be used again.
• Reserved: The address has been shown on a Checkout and is temporarily reserved for a PENDING Order.
• Locked: You have permanently locked the address for use outside of Zaprite (for example, in a consolidation transaction). Zaprite ignores transactions received to locked addresses.

Checkout Settings

Now that you have your ColdCard connected, you can choose to set this as your preferred Bitcoin payment method for your default Checkout.

Navigate to Checkouts on the main Zaprite menu. Toggle on the new wallet you just connected and Confirm and then Save the settings for your Checkout. When this wallet is in use, Zaprite will derive a new unused address for each Customer payment. You can always override the active payment methods on individual Checkouts for Invoices, Payment Links, Event Tickets, and other Zaprite products.

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Further Information

Gap Limit
We use a custom address reservation system which respects the default gap limit of 20 for all xPub connections. If the gap limit is reached we will pause new address generation until a previously reserved address becomes available again.

Video Guide

A video tutorial is also available on our YouTube channel.

Help & Support

If you run into any issues connecting your ColdCard wallet, or have general questions about using Zaprite, feel free to reach out at https://help.zaprite.com.