At this time, we do not support gift cards the common way.
Option 1: We have a concept of issuing voucher codes which can be redeemed by scanning the QR code on the POS. This voucher could be used online but works similarly to how Online Ordering vouchers work now. You have to apply the voucher code and it applies the entire balance of the voucher to the order.
Option 2: If you want to use your own 'gift cards', then those can be redeemed as defining custom payment type. However, in this case, we don't validate or track the balance on the 'card'.
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