Structure sheaves of definable additive categories

A 2-equivalence is described between the category of small abelian categories with exact functors and the category of definable additive categories with functors which commute with products and direct limits. There is a comparison, for definable additive categories, between the presheaf of finite-type localisations and the presheaf of localisations of associated functor categories. The image of the free abelian category in Mod-R is described and related to special bases of the Ziegler and rep-Zariski spectra restricted to the set of indecomposable injectives. In the coherent case there is a particularly nice form (which is essentially elimination of imaginaries in the model-theoretic sense).