A Dependently Typed Functional Programming Language

Building a modern functional compiler from first principles. (http://dev.stephendiehl.com/fun/)

Lenses, Folds, and Traversals - Join us on web.libera.chat #haskell-lens

lamdu - towards the next generation IDE

Algebraic graphs

A statically-typed linear functional language with graded modal types for fine-grained program reasoning

A language for intent-centric and declarative decentralised applications

Generalized bananas, lenses and barbed wire

The Art of the Propagator. See also:

A simple Depdently-Typed Language for Research and Learning

Optics via the profunctor representation theorem