Personalized results, and a Playground to see them

Search and recommendations can now take the shopper into account: their usual size, worked out from the purchases they kept, and how each item fits, learned from customers who exchanged sizes — “runs large”, “runs small”. When a size isn't certain it's suggested, never forced.

In the Playground you choose who is searching and compare the same results with and without their history, with an explanation of why each result moved.