We present a set of OCaml libraries and applications built to complete an interactive live-music setup. It integrates in the Jack (Jack Audio Connection Kit) ecosystem at a central position: MIDI sequencing. Through the MIDI “network,” a sequencer drives other pieces of software like samplers, effects, or synthesizers, while listening to commands from other entities (usually MIDI-enabled hardware, like keyboards or pedals). Vecosek aims at providing much more flexibility than the common sequencers by using embedded domain specific languages within a functional host language. A purely functional data-structure is the core description of a “music scene” that the sequencing engine understands and then higher-level EDSLs can be tailored to the kind of performance the composer/arranger needs. The software is already in use in the wild but would benefit from more varied application domains from the “functional programming & music” community: different performance situations, composition paradigms, or music education.