Doshii maintains multiple versions of our API. This is to manage integrations which have already been performed against older versions. Doshii manages the transformations between versions, POS on version 3 talking to partner on version X OR application writing to version X being stored in current version 3 formats.
The version is appended to the base URL after the first pos or partner segment and prior to the request, i.e. https://<environment[-readonly]>.doshii.co/<pos | partner>/<version>/locations (e.g. https://sandbox.doshii.co/partner/v3/locations)