Library Imports

You almost certainly already have a library. Years of tags, BPMs, keys, cue points, ratings, crates. Maybe in rekordbox, maybe in Engine DJ, maybe in Serato, maybe just a ~/Music/DJ folder full of FLACs. mixr reads all of it. Nothing gets copied, moved, or re-tagged — mixr opens the source library, pulls the metadata, and points at the files in place.

This page covers each library type one by one, where to find it on your machine, and where to paste the path into mixr’s Settings.

mixr never modifies the source library. Every importer is read-only — open the file, parse it, close it. Your rekordbox / Engine / Serato install stays exactly as it was. You can keep using both apps side by side.

What mixr imports

For every track, in every format, mixr pulls:

• Title and mix name (e.g. “Element (Original Mix)”)
• Artist and album / label
• BPM (analyzed BPM where available, falling back to user-set)
• Musical key (Camelot notation — 7A, 8B, etc.)
• Duration
• Genre
• File path — mixr plays the audio file straight off disk

Beat grids, hot cues, ratings, and waveforms are not imported in v0.1.3 — those live in formats specific to each source app and aren’t broadly portable. mixr re-analyzes BPM and beat-grids itself on first play if it needs to.

Tracks whose files no longer exist on disk (dead links — common after a drive move) are silently filtered out. You’ll see a smaller count than the source app shows; that’s the dead-link filter doing its job.

Where to set paths

All four import settings live in the same place:

1. Press , to open Settings.
2. Scroll to the ── Library ── section.
3. Each row is a Text row — press Enter to edit, type the path, press Enter again to save. Esc cancels.
4. Esc again closes Settings.

The four rows:

| Row | What it points at | |---|---| | Local Library Directory | A folder of audio files | | Rekordbox XML | Your exported rekordbox .xml | | Engine DJ Database | The Engine m.db SQLite file | | Serato Database | The Serato database V2 binary |

Each one is independent. Set all four if you’ve got data in all four — they show up as separate entries in the Browse menu so you can switch between them.

When a path is set, the corresponding entry appears in Browse (b) under the main menu. When a path is empty, that entry is hidden. So unconfigured importers don’t clutter your view.

Local Library — a folder of audio files

The simplest case. If your music lives in a folder, point mixr at the folder.

Paths to try first:

• macOS: /Users/you/Music/DJ or /Users/you/Music
• Linux: /home/you/music or /home/you/Music/DJ
• An external drive: /Volumes/Music (macOS), /media/you/Music (Linux)

Set it in Settings → Library → Local Library Directory.

mixr scans the directory recursively up to four levels deep (typical layout: Music/Genre/Artist/Album/track.flac), picking up .flac, .aac, .m4a, .mp3, .wav, .ogg, .opus. Metadata comes from the files’ tags (via symphonia — same metadata library used by every serious audio Rust project).

In the Browse view, this shows up as Local Library (last item in the menu when configured). Drilling in:

• Subfolders appear as menu rows: ▸ Techno/, ▸ House/, …
• At a leaf folder, you get a rich TrackList with BPM / key / duration columns — identical to a Beatport browse screen, so the same keys work (Enter to queue, a to queue all, Space to preview, Ctrl+F to filter).
• Each level also has a ⇲ All tracks (recursive) row that flattens the entire subtree into one flat TrackList. Useful for “show me everything in House” when you don’t care about the artist breakdown.
• Mixed folders (subfolders and audio files at the same level) show a ♪ Tracks here (N) row so you can jump to the files in the current folder without drilling further.

Tracks queued from Local Library play the same way Beatport tracks play — straight into the decks, beat-matched, blended.

Rekordbox XML — Pioneer desktop export

If you DJ with rekordbox on the desktop, you’ve got everything you need to share your library with mixr.

Export from rekordbox:

1. Open rekordbox.
2. File → Export Collection in xml format.
3. Pick a path — anywhere stable. macOS users often park it at ~/Music/rekordbox.xml; Linux/Windows wherever you prefer.
4. Click Save.

Set in mixr:

• Settings → Library → Rekordbox XML → paste the path → Enter.

The file’s a UTF-8 XML dump of every track in your collection with all 30-ish rekordbox attributes per track. mixr reads Name, Artist, Album, AverageBpm, Tonality (key), TotalTime, Location (the audio file path), and Genre. Other attributes (playlists, hot cues, beat grids, ratings) are skipped in v0.1.3.

In Browse, this shows up as Rekordbox. Selecting it parses the XML synchronously (typically under a second for libraries up to ~50MB / ~10k tracks) and pushes a flat TrackList of every track that still has a file on disk.

Re-export from rekordbox whenever you want to push library changes through — mixr re-reads on each open, so a fresh export is all you need.

Engine DJ — Numark Mixstream / Denon Prime

Engine DJ is the library format Numark Mixstream and Denon Prime hardware consume. It’s a SQLite database.

Desktop install:

• macOS / Linux: ~/Music/Engine Library/Database2/m.db
• Same on Windows under %USERPROFILE%\Music\Engine Library\Database2\m.db

USB stick (when you’ve prepped a stick for the controller):

• <mount>/Engine Library/Database2/m.db (modern firmware)
• <mount>/m.db at the stick root (older firmware)

But for USB sticks, you usually don’t need to set a path at all — mixr auto-detects the stick (see USB sticks below). The Settings → Library → Engine DJ Database row is for pointing at your desktop Engine library.

Set in mixr:

• Settings → Library → Engine DJ Database → paste the m.db path → Enter.

mixr reads the modern Engine v3 schema by default (Track table — title, artist, album, genre, bpmAnalyzed (preferred) or bpm (fallback), key as Camelot wheel integer 0-23, length, path). Engine stores paths relative to the database root, so mixr resolves them against <root>/Engine Library/. On older databases it falls back to a legacy schema query — best-effort.

In Browse, this shows up as Engine DJ.

The key integer round-trips to Camelot: 0 → 1A, 1 → 1B, 2 → 2A, … 23 → 12B — so what you see in mixr matches what Engine shows you on the controller.

Serato Database V2

If you DJ with Serato, your library lives at:

• macOS: ~/Music/_Serato_/database V2
• Windows: %USERPROFILE%\Music\_Serato_\database V2
• Linux: rare (Serato isn’t officially supported), but if you’ve hand-installed it, look under ~/Music/_Serato_/database V2

(Yes, “database V2” with a space and no extension — Serato’s choice, not ours.)

Set in mixr:

• Settings → Library → Serato Database → paste the full path including the space → Enter.

The file is a proprietary tag/length/value binary (reverse- engineered by the mixxx project). mixr reads the otrk track records and pulls pfil (path), tsng (title), tart (artist), talb (album), tbpm (BPM as string), tkey (key), tlen (duration in “MM:SS” or seconds), tgen (genre). Track paths resolve against the _Serato_ parent (so the library root is typically ~/Music/).

In Browse, this shows up as Serato.

Crates and smart crates aren’t surfaced in v0.1.3 — you get one flat list of every track in the database. If a crate-aware view is something you’d use, ping in.

USB sticks — auto-detected

Plug in a USB stick that’s been formatted for a DJ controller, and mixr finds it. No config needed.

mixr polls mount roots every 2 seconds:

• macOS: /Volumes/*
• Linux: /media/$USER/*, /run/media/$USER/*, /media/*, /mnt/*
• Windows: drive letters D: through Z:

For each mounted volume, mixr looks for two known marker layouts:

| Marker file | Recognized as | |---|---| | <mount>/Engine Library/Database2/m.db | Engine DJ stick | | <mount>/Engine Library/m.db | Engine DJ (legacy) | | <mount>/m.db | Engine DJ (older firmware) | | <mount>/PIONEER/rekordbox/export.pdb | Rekordbox stick | | <mount>/PIONEER/USBANLZ/ | Rekordbox (newer layout) |

When detected, the stick shows up in Browse as an entry like USB: SANDISK_64GB (Rekordbox) or USB: STICK1 (Engine DJ), listed below your configured library entries. Drill in to load every track that’s still on the stick.

Pioneer’s export.pdb is the DeviceSQL binary format CDJs read straight off the stick. mixr’s .pdb parser handles the standard layout (Tracks / Artists / Genres / Keys tables, page-and-row-group walk, both DeviceSQL string encodings). Paths inside the .pdb are stored relative to the stick root, so mixr joins them against the mount.

Eject the stick and mixr drops it from Browse on the next 2s scan.

Serato USB sticks aren’t auto-detected — Serato doesn’t have a standard USB layout the way rekordbox and Engine do. If you’ve got a Serato library on an external drive, point at it manually with Settings → Library → Serato Database (the path will look like /Volumes/SANDISK/_Serato_/database V2).

Browse semantics across all libraries

Every library entry in Browse behaves the same way once you’re inside:

• Drilldown with Enter or →. Back out with Esc or ←.
• A TrackList is the rich four-column view (artist, title, BPM, key, duration). Press Enter on a track to queue it. a queues every track on screen. Space previews. Ctrl+F filters live as you type.
• mixr’s queue and dashboard don’t care which library a track came from — it’s all just tracks. You can queue one off rekordbox, then one off a USB stick, then one off Beatport, and mixr will blend the three the same way.

Troubleshooting

The library entry doesn’t appear in Browse.

The corresponding Settings row is empty. Open Settings (,), scroll to Library, paste a path, press Enter to save. Browse rebuilds automatically next time you open it (b).

The library entry appears but is empty.

Most likely the source library is full of dead links — tracks the source app remembers but whose files no longer exist on disk (drives moved, files renamed outside the app, external drive detached). mixr filters dead links because it can’t play them. Re-mount the external drive or re-sync the source app to its files.

A USB stick doesn’t show up in Browse.

Check three things:

1. The stick is actually mounted. On macOS, it should be visible in Finder’s sidebar. On Linux, run mount | grep -i <stickname>.
2. The stick has one of the marker files mixr looks for (see the table above). A USB stick formatted as plain music with no DJ software exporter on it won’t be detected — that’s a Local Library case (point Settings → Local Library Directory at /Volumes/STICKNAME).
3. Wait 2 seconds and re-open Browse. The poll runs at 0.5Hz, so right after plugging in there’s a small lag.

A path with spaces doesn’t work.

mixr handles spaces in paths fine — paste the whole thing including the space, no quoting needed. The most likely failure is a typo or trailing whitespace. The placeholder text in each Settings row (/path/to/database V2, etc.) shows the expected shape.

macOS vs Linux path formats.

mixr uses native filesystem paths — no URL encoding, no file:// prefix.

• macOS: /Users/you/Music/..., /Volumes/...
• Linux: /home/you/music/..., /media/you/..., /mnt/...
• Windows: C:\Users\you\Music\... (forward or backslashes both work)

The one exception is the contents of a rekordbox XML, which stores paths as file://localhost/Users/... URLs — that’s rekordbox’s choice, and mixr decodes them transparently. You don’t need to touch the XML.

Re-scanning after I added tracks.

mixr re-reads the library file every time you open the corresponding Browse entry — b then drill into Rekordbox / Engine DJ / Serato / Local Library. There’s no cache to bust. For rekordbox specifically, you need to re-export the XML from rekordbox first (it doesn’t auto-update) — File → Export Collection in xml format → overwrite the file mixr points at.

Multiple libraries with the same track.

A track will show up in every library that knows about it. Queueing it twice from two different sources will queue it twice (mixr treats them as separate queue entries since the paths might differ). Use the queue view (q) to clear duplicates.

What’s next

Once you’ve got a library mixr can see, the rest of the app works exactly the same as it does for Beatport:

• Queue a couple of tracks with Enter or a.
• Press d to return to the dashboard and watch them mix.
• Hot cues (Shift+1..Shift+4), mixer overlay (z), Claude DJ (C), MIDI controllers — all of it works on your local library the same way it works on Beatport. The source of the audio is the only thing that changes.

If you want to dig into the Beatport side specifically, see the Getting Started page. If you want the exhaustive list of every importer field and code path, FEATURES.md is the source of truth.