The category of matrix factorisations is a differential graded category associated to any isolated hypersurface singularity, whose associated cohomology category is a Calabi-Yau triangulated category. This triangulated category carries additional structure, namely A-infinity products, which are important in the deformation theory of matrix factorisations and also in mathematical physics. In this talk I'll present a new approach to these A-infinity products based on idempotent A-infinity functors and a kind of "categorified" residue.