To generate a melody, one or more machine-readable constraints are accepted from a user through a user interface. The constraints include rhythm constraints and pitch constraints. A sequence of musical elements is generated based on the constraints, each of the musical elements specifying, in machine-readable data, a musical pitch or silence and a duration of the musical pitch or silence. The pitch constraints prescribe pitches in the sequence of musical elements and the rhythm constraints prescribe rhythm of the sequence of musical elements. The sequence of musical elements is rendered in human-perceivable form as a melody.