Bespoke cashback website (to track affiliate income by individual customer)

We are looking for a custom platform that we can link into an existing Squarespace 6 website that will track sales generated with affiliates (on a similar basis to say Quidco). We want a simple, clean solution as our focus is not on paying our cashbacks to our members but to simply track and reconcile the affiliate links that they have clicked through on, and if/when they complete a transaction (via cookies). We can reconcile this against the affiliate revenue reports we receive from each supplier. Members will need to have access to a running report on where/when/what they have purchased from affiliates via our site.