Digital audio is omnipresent in our lives, from your cellphone’s ringtone to streaming music on Spotify. The main audio formats were created in the early 90s stood the test of time and survived through technology advancements. During the first part of this talk will take a look at the anatomy of these popular formats, why they were designed like that and what makes them durable. Then we will talk about the challenges and lessons learned designing and implementing a generic Go API for digital audio. This talk was designed for curious attendees of all levels. The focus on audio format is mainly there as an excuse for us to reason about API design in an unfamiliar/unbiased context.