SortYourMusic is a client-side web application that lets users sort their Spotify playlists by musical attributes like tempo, energy, danceability, loudness, valence, and more. It uses the Spotify Web API with PKCE OAuth for authentication and runs entirely in the browser with no backend server. The repository contains two versions: an older monolithic implementation (web/) using jQuery, Bootstrap 3, and Underscore.js, and a modern modular rewrite (web2/) using vanilla ES modules, CSS custom properties, and no framework dependencies. The modern version demonstrates clean architecture with separate modules for authentication, API calls, state management, views, and utility functions. Key features include BPM filtering with doubled BPM support, artist separation ordering, and the ability to save sorted playlists as new copies or overwrite existing ones.