Someone spent years turning a shelf of CDs into files: ripping each one, checking track names, fixing compilation artists, finding the right covers. Then a well known music player rewrote the information stored inside those files.
It duplicated and overwrote the details on 33 albums. The music still played. Every album was put right in the end; a player should never have touched them.
Stellody was written because of that afternoon. One rule underlies everything else: your files are opened to be read and never to be changed. If an album is muddled, Stellody tells you and leaves the file alone; what to do about it stays your decision.
Anybody can write "we never touch your files" on a website, then quietly stop meaning it. In Stellody it is checked by the test suite every time the checks run; if it stopped being true the suite would fail.
The part of Stellody that could write to a file is kept out of reach of every part that opens your music. Not by care, by construction.
No stray database, no hidden cache, nothing left behind. What Stellody learns is kept in its own place, away from your music.
Only three parts of Stellody reach the internet themselves: album art search, the update check and discovery. Two buttons only hand an address to your browser. All five are below; playing music uses none of them.
An unplugged drive or a half finished scan never makes Stellody forget your albums; missing files are flagged, not thrown away. Back up library on the File menu keeps everything it knows in one zip.
Playing a collection is the easy half. The harder half is what is not in it: the album an artist you love made while you were not looking; the artist two steps sideways from one you have played for twenty years. That question used to need a friend with better records than yours.
Stellody answers it from what you own. It reads your artists in the genres you tick, asks MusicBrainz what else they released and ListenBrainz who resembles them, then lists what you do not hold.
There is no profile, no listening history and no account, because nothing needs them: the question is asked from your own files and the public record alone.
A recommender tells you what people like you played next, learned from watching you. This is your collection asking what is missing from itself. Where a catalogue cannot answer for an artist, Stellody says so rather than quietly shortening the list.
Stellody does not know who you are: no account, no profile, no newsletter and no record of what you listen to. Only searches you ask for name any of your music. A cover search names one album's artist and title; a discovery search names artists and titles from the genres you ticked. Your music plays with the internet switched off.
Five things reach outside your computer at all. Here are all five.
Only when you ask, one album at a time. Stellody asks MusicBrainz which releases the album has and the Cover Art Archive for their pictures, then shows the covers found so you can pick one. Every picture comes over a secure connection, even where the archive lists a plain address.
A few seconds after starting, then once a day while running, Stellody asks whether a newer version exists. It sends nothing about you or your music, not even your version; it asks for one small public page and compares on your own machine.
It stays quiet unless there is something new. Then Download hands your browser the file for your platform (the release page when there is none), the same act as the two entries below. You can skip a version for good.
Only when you ask. You tick the genres; Stellody asks MusicBrainz and ListenBrainz what those artists released that you do not hold and who else sounds like them.
What goes out: those artist names; the MusicBrainz identifiers the catalogue gives back for them and for the similar artists it suggests; the fixed settings each request states (the answer's format, how many results, where a following page starts, which release types to list, which details to include and which similarity algorithm to use); a user agent naming Stellody, its version and the project's contact address. Where the catalogue holds several artists under one of your names, up to three titles of albums or tracks you hold under that name go too, so it can tell which is yours. While Other volumes of series is ticked, the titles of compilations you hold in those genres go too (a DJ mix among them), with each one's series name, to find the volumes you lack. The language asked for is fixed at any. Nothing else: not your collection as a whole, not a count of it, not a word about you or your machine. Tick nothing and nothing leaves.
Tick albums a search found, choose a shop and Stellody hands your browser that shop's own search address for each. Stellody connects to no shop and has no affiliation, referral or affiliate tag; what happens next is between you and the shop.
Its tooltip offers to buy the author a drink. One person writes and looks after Stellody; that button is how the work gets paid for and the whole of the asking.
Pressing it hands the address to your browser; Stellody itself connects to nothing. Nothing prompts or reminds you and nothing changes if you never press it.
Stellody plays FLAC, MP3, Ogg, Opus, WAV, AIFF, M4A, WMA, WavPack and AAC. It does not read Monkey's Audio, Musepack, DSD, TAK, TrueAudio, CAF or M4B audiobooks: the one thing worth checking before you download.
A file in one of those formats is named in its health report rather than left out without a word, as is one whose details cannot be read. You find out rather than wonder.
WMA, WavPack and AAC rest on weaker evidence: with no such file here to test, each is proved against one the test suite encodes.
That exercises the whole path through Stellody but says nothing about what an old Windows Media ripper wrote. If one of yours reads wrongly, please report it.
It is a player and only a player. It does not stream, rip CDs, sync to a phone or reorganise your collection by rewriting files.
It tidies muddled labelling in its own view and keeps that if you say so; it never rewrites the files themselves. A control that cannot act just now is greyed out.
Windows, macOS and Linux. On Windows it installs for one user; on macOS it is dragged into Applications; on Linux it installs for one user too.
You do not need any of this to use Stellody. The working behind the claims above has a page of its own: how each rule is held by a test and the measurements behind the design.