Monad Transformer

A monad transformer is a design pattern in functional programming that allows combining multiple computational effects—such as handling state, errors, or asynchronous operations—into a single, cohesive structure. Think of it as a modular toolkit that stacks different behaviors, enabling complex operations to be managed cleanly and compositionally. This makes it easier to write clear, reusable code when dealing with multiple layers of effectful computations, without losing the simplicity of working within each individual effect. Essentially, monad transformers help manage complexity by blending different "workflows" into one unified framework.