What happens with a Deezer link
Deezer is one of the music catalogues the bot already uses to identify songs, so a Deezer link is one of the most precise things you can send. For a song, the bot asks Deezer's public API for the track and gets more than a title and a name:
- every contributing artist, not only the lead – the difference between finding "First Person Shooter" and finding "Drake – First Person Shooter ft. J. Cole";
- the ISRC, the recording's international code, which ties the song to one specific recording;
- the album and its cover, in high resolution.
The audio is then located on public sources the same way as for a Spotify link and compared with those details – artists, title, length. Covers, live versions, remixes and previews are rejected. The result is copied into an M4A file without re-encoding and tagged with what Deezer said.
Albums and playlists
Send an album or a playlist link and the songs are listed as buttons, each with its artist and length. Tap any of them to download it. For the whole album in one tap, find it by name with the album downloader – it reads Deezer's album tracklists too and adds a Download all button.
Short links
The Deezer app shares links like deezer.page.link/abc123. These do not say what they point to until they are opened, so the bot follows the link first, then treats it as the track, album or playlist it turns out to be.
Why we don't download Deezer's own audio
Deezer's streams are encrypted, and the key comes from a logged-in, paying account. Getting around that would mean circumventing DRM tied to someone's subscription, and we do not do it. Reading Deezer's public catalogue to identify the song, and fetching the audio from public sources, gives you the right song without it.