Substrate

We present Type Classes: a series of focused video courses on Haskell, Nix, and related subjects.

Profunctors are bifunctors that are contravariant in their first type argument and covariant in their second one.

it is often a surprise for people to learn that function composition is the `fmap` of functions

In celebration of one year of Type Classes, annual memberships are half-off through June 30.