Part 3 examines the Profunctor typeclass in detail: the dimap operation, its laws, and the Strong and Choice extensions that enable profunctors to work with products and sums. These building blocks …

Part 1 showed paired operations like encode/decode and serialize/deserialize. Part 2 builds the intuition for why these pairs fit together: one direction produces data (covariant), the other consumes …

Software development involves many paired operations: encoding and decoding, serializing and deserializing, encrypting and decrypting. Profunctors capture this pattern. Part 1 introduces the …