Abstract We exhibit the cartesian differential categories of Blute, Cockett and Seely as a particular kind enriched category. The base for enrichment is category commutative monoids—or in straightforward generalisation, modules over rig k . However, tensor product on this not usual one, but rather warping it by certain monoidal comonad Q Thus sense, skew sense Szlachányi. Our first main result ...

We give a 3-universal property for the Karoubi envelope of 2-category. Using this, we show that 3-categories finite semisimple 2-categories (as introduced in arXiv:1812.11933) and multifusion categories are equivalent.