Progger 2.0

A guitar scale, mode and chord reference with a phrase generator, a practice drone and a pixel frog guitarist. Everything runs in your browser: no account, no AI credential and no music database.

Live at progger.studio.

What it does

Explore scales and chords

• 28 scales and modes in every key: the major, harmonic-minor and jazz melodic-minor modes, pentatonic and blues, whole tone and both diminished scales. See scale coverage.
• A continuous neck up to fret 24 with connected 3-notes-per-string and 2-notes-per-string shapes, overlap with neighboring shapes, adjustable view width, a whole-neck overview, a left-handed view and text equivalents. See connected neck.
• 32 chord qualities, including 11ths, 13ths and altered tensions, with complete, reduced and rootless guitar voicings. See advanced chords.
• Hear any voicing exactly as drawn: a short synthesized strum that keeps the inversion, muted strings and omitted notes. See voicing audio.

Match a progression

• Type chords (slash basses included) and Progger lists the scales that fit, grouped across the whole progression, with an optional home note and a palette per chord. Up to 32 chords per progression.

Practice

• Phrase generator: builds a 2- or 4-bar guitar line over the selected scale and chord, then plays it and shows it on the neck. Tempo runs from 40 to 240 BPM, with adjustable swing and optional looping. Phrases are made by seeded rules in the browser with no network calls.
• Drone: holds the key under your playing. Choose Reed or Bow (both synthesized with Web Audio) or Cello (CC0 samples), and set the volume.
• Practice tray: save phrases, scales and chords, reopen them later, and download a saved phrase as ASCII guitar tab or a MIDI file.

Scenes

• Three illustrated scenes (The Pond, Tidepool and Twilight), each with a day and night version. The choice is saved on your device and the transition respects reduced-motion settings. See scenes.

Progressions, alternate tunings, accounts and offline install are not built yet. Some movable shapes need wide stretches. Diagrams show positions, not prescribed fingerings.

Run it locally

Requires Node 22.13 or later.

npm ci
npm run dev

To try the production build locally:

npm run build
npm start -- --port 3000 --ip 127.0.0.1

If a system libvips install makes Sharp try a native build, use SHARP_IGNORE_GLOBAL_LIBVIPS=1 npm ci.

Checks

npm run lint
npm run typecheck
npm test
npm run build

npm test uses Node's built-in test runner. Some tests drive real browsers through Playwright; install them once with npx playwright install --with-deps chromium firefox. The full suite takes a few minutes.

CI runs the suite as three slices in parallel jobs, and each can run on its own:

• npm run test:unit: no browser
• npm run test:browser: the app and component tests in Chromium and Firefox
• npm run test:render: the long drone audio renders in both browsers

scripts/run-tests.ts decides the slices from each test's imports. Pass test files to run only those, for example npm run test:browser -- tests/phrase-panel-loop.test.ts.

Project layout

• app/: the page, layout and styles
• components/: React UI (neck, voicings, phrase panel, drone, practice tray)
• lib/: browser-independent music logic (music.ts, harmony.ts, phrase.ts, drone.ts) and audio
• tests/: unit and browser tests
• docs/: design notes and verification records

Built with React, TypeScript and Vite through vinext, and deployed on Vercel. See Vercel deployment.

Credits

• Cello drone: excerpts of the Versilian Studios VSCO 2 Community Edition cello section, CC0 1.0. See public/audio/drone/LICENSE.md.
• Fonts: Maple Mono v7.9 (SIL Open Font License 1.1, see public/fonts/maple-mono/) and Silkscreen (SIL Open Font License 1.1, loaded through Google Fonts).
• Scene artwork and the frog mascot were generated for this project. Prompts are recorded in docs/.

License

Progger is released under the MIT License.

Third-party assets keep their own licenses:

• Maple Mono fonts: SIL Open Font License 1.1, see public/fonts/maple-mono/LICENSE.txt.
• Cello drone samples: CC0 1.0, see public/audio/drone/LICENSE.md.