The show editor

A show is the list of tracks the DJ will play, and what you want to happen inside them.

You import tracks from disk, place markers on them, and give each a pre-roll — the lead time over which the marker announces itself before it lands. That pre-roll is what lets an operator get ready, and a console preload.

A marker is a position inside a track, not a clock time. The same show replayed the next day at another hour therefore lands correctly with nothing to adjust.