jev-playground (wustep)
Can a System One model steer music? Jev picks only enum labels for a composition plan; code writes, engraves and plays the notes.
Overview
Jev Playground by wustep tests whether a decision model can steer music across styles. Jev, or an offline stub behind the same interface, decides only enum labels: where the tune sings, how it moves, what holds it up, then form, key, metre, palette, tempo and dynamics, and for each four-bar slot a harmony-book phrase and per-bar contours. App code expands the plan into chords and notes, engraves it with VexFlow, plays it and exports MIDI.
Styles include Bach, Beethoven, Chopin, Debussy, Philip Glass, Hans Zimmer, Laufey and Elijah Fox. A test requires each style's most typical plan to differ from every other on register, motion and accompaniment, and classical styles are compared against public-domain MIDI. Other routes include an absurd trolley-problem demo where Jev makes Choice, Score and Noul judgments and code writes every sentence, plus offline inbox-triage and matching demos that use client stubs rather than live Jev.
What the decision model decides
| Type | Question | Answers |
|---|---|---|
| Choice | Which form, key, metre and palette should this piece use? | — |
| Choice | Which harmony-book phrase fits this four-bar slot? | — |
| Yes / no | Would most people pull the lever in this trolley problem? | yes · no |
How it works
- Choose a style
- Jev (or the stub) picks enum labels for the plan
- Code expands the plan into chords and notes
- Engrave with VexFlow, play and export MIDI
Strengths
- Works offline with a heuristic stub
- Tests enforce that styles actually differ
- Jev never generates notes or text
Caveats
- Some demos use client stubs, not live Jev
- Living artists' styles have limited reference data
Getting started
npm install && npm run dev, then open http://localhost:5173At a glance
- Type
- App
- Status
- prototype
- Language
- TypeScript
- Runtime
- Vite web app
- Has code
- yes
- Has tests
- yes
Use cases and integrations
How curated lists describe it
Can a System One model steer music? Jev picks the plan (enums only); code renders sheet, audio and MIDI.
logicrw/awesome-jev-projectsCan a System One model steer music? Jev picks the plan (enums only); code renders sheet, audio and MIDI.
hellogumbo/awesome-jev
Frequently asked questions
Does Jev write the music?
No. It picks plan labels; code writes the notes.
Can I run it without a key?
Yes. An offline heuristic stub sits behind the same interface.
What else is in the app?
A trolley-problem demo using Jev judgments, plus offline inbox and matching demos.
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Appprototype