# Code Patterns

- [Fun with flat\_map (in Ruby)](/code-patterns/fun-with-flatmap.md): How I accidentally learned about...
- [Enumerating Union Types in Elm](/code-patterns/enumerating-union-types-in-elm.md): aka Sum Types, now officially Custom Types
- [Software Design Patterns](/code-patterns/software-design-patterns.md)
- [Authn / Authz](/code-patterns/authn-authz.md): Authentication and Authorization