Explore a simple, high-performance effect system based on tag unions in this conference talk from YOW! 2022. Dive into functional programming concepts as Richard Feldman, an expert in the field and author of "Elm in Action," demonstrates how to implement this system in the Roc programming language and OCaml using polymorphic variants. Learn how to easily mix I/O operations with different failure modes while maintaining exhaustiveness checking on error cases. Discover techniques for identifying which functions use specific effects and enforcing compile-time restrictions on effect usage. Gain insights into creating more maintainable and predictable code through this innovative approach to handling effects in functional programming.