Lightspeed is not currently seeking new payment processing integrations. There are gateways available in some regions to allow integrated payments, a list is available here.
If you’re looking for Lightspeed’s API documentation to build an integration for one specific customer, please contact our support team for assistance with the API setup. https://www.lightspeedhq.com/support/
If you’re looking for Lightspeed’s API documentation to build an integration for one specific customer, please contact our support team for assistance with the API setup https://developers.lightspeedhq.com/ecom/introduction/introduction/