Start by deciding whether you are replacing Spotify as a music catalog, a player, or a habit engine. Spotify combines licensed streaming, account sync, recommendations, podcasts, shared playlists, queue control, and device handoff under one account. Open source options usually split those jobs. A personal library server is a different bet than a local player, a podcast client, or a tool that manages playlists for files you already own. The key question is where your music will come from after the switch - purchased files, ripped discs, public streams, independent downloads, or another paid catalog used alongside open source software.
Expect the biggest gaps around catalog access and convenience. Open source software cannot legally include Spotify's licensed catalog, so any track you only streamed must be sourced another way or left behind. Discovery features may be less tuned because they do not have the same listening graph behind them. Spotify Connect, car integrations, smart speakers, collaborative playlist behavior, lyrics, and gapless playback can vary widely. Offline playback is possible in many setups, but it depends on the mobile app, file format support, storage limits, and whether your server is reachable before the device goes offline.
Migration is mostly metadata matching, not a true account transfer. Export playlists while your Spotify account is still available, either through Spotify's data download or a tool that reads your account with permission. You can usually preserve playlist names, track order, artists, album titles, and sometimes identifiers, but not the audio files. Liked songs, saved albums, followed artists, podcast subscriptions, and listening history often arrive as separate data that needs cleanup. After import, expect mismatches from regional editions, remasters, live tracks, unavailable songs, and inconsistent tagging in your destination library.