Monads, a famously difficult concept from Haskell, may be the key to building approachable libraries in JavaScript. jQuery, for instance, is probably the most widely-used monad in the world, taking advantage of the monad approach to create readable and chainable code, While building monads requires some extra effort and structure, once they're together, they make JavaScript programming much simpler. This guide walks developers through the many changes in approach demanded by monads, helping them build easily reused JavaScript.