Oscine
An instrument stage and music studio for macOS. Eleven instruments, all synthesized in the app — no samples, no SoundFonts — and a stage that renders every note as light.
the stage
Additive piano, Karplus‑Strong guitar and bass, a twelve‑piece drum kit, FM bells, a supersaw pad, electric piano, strings, brass, organ, and harp — every voice is live DSP behind a shared reverb bus and a safety limiter. Instruments share one continuous surface split by hairlines: busy ones grow, idle ones collapse to micro‑strips.
Everything is playable by hand, mid‑song — cursor or computer keyboard — through the same synth. An FL‑style piano roll builds songs note by note; playlists queue them; the export engine bounces to WAV, AIFF, ALAC or AAC at up to 96 kHz. A record button captures performances as replayable projects.
the repertoire
Every piece is note‑level JSON generated by a committed Python script — the script is the composition’s source, and a validator enforces ranges, tablature, and playability.
A fun project, honestly — and my first with claude‑fable‑5, testing two things at once: whether an LLM could build a native macOS app at this size, and whether it could compose. That’s also the point of the architecture: songs are note‑level JSON emitted by committed scripts, so the app doubles as a set of tools an LLM can use to produce music itself.