With 4,300+ GitHub stars and native mobile apps on three platforms, Black Candy transforms any VPS into a private Spotify-style streaming service for your personal music collection. The Ruby on Rails 7 backend with Hotwire Turbo and Stimulus delivers a responsive single-page-feeling web player supporting album browsing, artist views, playlists, favorites, and queue management without full page reloads. Point it at a media directory containing MP3, FLAC, OGG, AAC, or WAV files and Black Candy indexes metadata, fetches album artwork from Discogs API, and begins streaming immediately with on-the-fly transcoding that adapts bitrate to client bandwidth. Multi-user support gives each account independent playlists, favorites, and listening history while sharing the same music library — ideal for families or shared households. Native iOS, Android, and F-Droid apps maintained as separate repositories provide offline caching, background playback, and server discovery for mobile listening. The admin panel manages user accounts, configures media paths, and sets Discogs API tokens for automatic cover art retrieval. Deployment requires one Docker command — `docker run -p 80:80 ghcr.io/blackcandy-org/blackcandy:latest` — with persistent storage volumes for the SQLite database and media directory. For larger deployments, switch to PostgreSQL via environment variables with dedicated database URLs for ActionCable, SolidQueue, and SolidCache. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. MIT licensed.