follows what you're playing
Music app, Traktor (broadcast or the in-app bridge) and djay all feed the seed; the most recently active healthy source wins, and a forced one never silently falls back.
the selector
Segue
A floating macOS overlay for DJs and selectors. While you play in the Music app, Traktor or djay, Segue watches the current track and recommends harmonically compatible ones from your own library — key and BPM windowed, ready to drag into a playlist or a deck.
Swift 6
macOS
Camelot + BPM
HUD overlay
The hard part of a set isn't playing the track, it's picking the next one — three minutes to find something that fits, in a library too big to hold in your head. Segue follows whatever you're already playing: the Music app's selection or now-playing track, Traktor over its own broadcast stream or a purpose-built in-app bridge, djay through its library. A coordinator decides which source wins, and the answer is always a dark HUD panel that sits on every Space and never steals focus from the app you're mixing in.
Only tracks inside a hard ±key/±BPM window are eligible — same-suffix Camelot keys within tolerance plus the relative major/minor, with optional loose-suffix and double/half-time matching — then ordered by key, tempo and tag affinity, or shuffled once per seed so it doesn't reshuffle underneath you. Key badges are tinted around the colour wheel, so compatible keys read as neighbouring hues at a glance. Segue also remembers the night: tracks you've actually played get demoted, marked or excluded, and Vocal Match deliberately alternates — a vocal seed pulls instrumentals, and the reverse.
Everything is a drag source. Pull one row, or a Finder-style selection of them, straight into a Music playlist or onto a DJ deck; park the maybes in the Crate, which empties itself as you play them. Your library is read-only by construction, nothing is guessed — an unmatched DJ track says so by name rather than seeding from the wrong thing — and ⌘⌥S makes the whole overlay disappear for the length of a tricky mix.
highlights
a Camelot window, coloured
Hard ±key/±BPM eligibility with relative major/minor and optional double-time, and key badges tinted by hue so compatible keys look like neighbours.
rows drag out
Click, ⌘-click and ⇧-click like Finder, then drag one row or the whole selection into a Music playlist or a DJ-app deck as plain file drags.
a holding bin
Pin what you're planning to play; a qualifying play takes it out again. Right-click the header to split the Crate into its own window.
knows the night so far
Played tracks get demoted and dimmed, marked in place, or excluded — your choice — and Vocal Match alternates vocals with instrumentals.
never steals focus
Non-activating HUD glass on every Space, self-sizing from a fixed bottom edge, hidden and shown from any app with the ⌘⌥S global hot key.
under the hood
- Swift 6, Xcode 26 — strict concurrency on macOS 26, Apple Silicon, with no third-party dependencies at all.
- read-only by construction — the library is indexed through iTunesLibrary; Segue cannot modify a track, a tag or a playlist.
- Traktor, two ways — a loopback Icecast sink that parses Traktor's own broadcast metadata, plus a from-scratch QML bridge that POSTs four-deck snapshots.
- Xone:96 over CoreMIDI — when you mix externally it reads the physical channel faders (CC 0–3 only, never the crossfader) to work out which deck is live.
- honest states — versioned JSON with atomic writes and corruption quarantine; denied permissions, stale sources and unresolvable tracks are named instead of guessed at.