For saleWorking prototype

GroovePost Pocket Drum Machine

AI-generated 16-step drum studio with synthesized sounds, swing, tap tempo, saved patterns, and four-bar stereo WAV export.

Screenshots supplied by the seller.

Open demo (opens in a new tab)

Description

AI generated by Codex for Shai. GroovePost is a working prototype rhythm studio with the personality of a compact hardware drum machine: a dark panel, peach kick pads, lavender snares, and yellow hi-hats.

Build a 16-step pattern across three synthesized voices, set tempo from 60–180 BPM, add swing, mute tracks, tap a tempo, and save up to 30 named grooves. Presets provide three starting points.

Export four bars to a 44.1 kHz, 16-bit stereo WAV with a short release tail. Audio is synthesized in the browser; no sample packs or paid APIs are required. JSON backups preserve the current groove and pattern bank.

The buyer receives full editable source, core tests, setup documentation, and deployment configuration. Private source handover is arranged by the seller; demo hosting-account transfer and ongoing support are not included.

Condition

Development stage: Working prototype (seller-declared)

Seller-declared: provided by the seller, not independently verified by SellMyVibe.

Solo creator
Mainly AI-generated
Under one month in development
Mobile-friendly
Tests included
Setup guide included
Demo available

What works

16-step / three-voice synthesized kick, snare, and hi-hat sequencer in fixed 4/4 time
Tempo 60–180 BPM, swing 0–35%, tap tempo, master volume, and per-voice mute
Three original preset patterns, clear steps, and up to 30 named saved patterns
Four-bar 44.1 kHz / 16-bit stereo WAV export with a 0.35-second release tail
Automatic browser-local saving and JSON backup/import
Responsive layout with horizontally scrollable pads on small screens

What’s unfinished

No sample import, live recording, MIDI, arrangement timeline, effects, or DAW synchronization
Playback stops when the tab is hidden; browser/device audio latency and compatibility vary
WAV includes a release tail and is not a seamless bar-trimmed loop
No sign-in, cloud sync, or shared sessions

Included assets

Full source code

Documentation

Deployment setup

Test suite

Technologies

HTML5, CSS3, Vanilla JavaScript ES modules, Browser localStorage, Web Audio API

Setup requirements

Unzip the source. Run python3 -m http.server 8080 in the app folder and open http://localhost:8080, or deploy the folder to a static HTTPS host. No build or API key is needed. Node 20+ can run the included test.mjs. See README.md for app-specific limitations and QA.md for validation.

Dependencies and ongoing costs

No third-party libraries, paid APIs, backend services, or sample packs required. Uses built-in browser features and system fonts; all visual styling is original code. Static hosting may be $0/month within free-tier limits; paid hosting, traffic overages, and custom domains may cost extra.

Known limitations

Working prototype, fixed 4/4 and three synthesized voices. Audio is browser- and device-dependent; the browser Play state and non-silent WAV output were verified, but no independent listening-quality or latency certification was performed. Playback requires a user gesture and stops when the tab is hidden. Browser data can be cleared; export backups. No independent security audit.

Listings are reviewed for completeness and clarity before publication. Approval is not a guarantee of quality, ownership, security or commercial success. Read the details and ask questions before buying.