Explore functional programming concepts and their application in JavaScript to create more maintainable code in this 53-minute conference talk from the Reliable Web Summit 2021. Discover how to implement core functional programming principles, refactor common code structures, and improve code composition, testing, and future maintenance. Learn about purity, line functions, accumulation functions, cognitive load reduction, immutability, function signatures, function composition, and more. Gain insights into using functions as values and applying techniques like filter and reduce to write cleaner, more efficient JavaScript code.