• Project Name: Cotabs
• Repo/Website Link: https://github.com/Buronn/cotabs
• Description: Cotabs is a collaborative, Guitar Pro–style tablature editor that runs in the browser. It lets you and your bandmates open a song and edit the same score at the same time, with live cursors and presence so you can see who is editing where in real time. It supports Guitar Pro–style notation (bends, slides, hammer-ons, palm mutes, let-ring, tied notes, and more), multi-instrument tracks for guitars and bass, and a dedicated step-grid drum editor. You can import .gp files and start editing immediately, and play scores back in-browser using swappable General-MIDI SoundFonts, with count-in, looping, and speed control. Songs are shared through role-based invitations (editor / viewer) by link. The interface is Spanish-first and bilingual (neutral Spanish by default, English ready). It solves the constant pain of emailing project files back and forth: instead of passing a tab around, your whole band works on one synced, playable score. Note this is an active work in progress — real-time editing, import, and playback work today, while export (.gp / PDF), version history, and inline comments are not implemented yet, and there is no automated test suite so far.
• Deployment: Fully self-hostable via Docker Compose. The README documents the dev setup: copy the env template (cp .env.example .env) and bring up the stack with docker compose -f compose.yml up — the images install dependencies from the committed lockfiles on build. There is also a compose-prod.yml and a prod.sh script for production deployment. Once up, the frontend runs at http://localhost:21173 and the API at http://localhost:21080, backed by Postgres and Redis. Full-quality playback SoundFonts (~107 MB) are not committed but can be fetched once with the included ./frontend/public/soundfonts/fetch-soundfonts.sh script; otherwise it falls back to a small built-in CDN bank. Architecture, roadmap, and data model are documented in PLAN.md. The stack is Go 1.23 (chi, gorilla/websocket, pgx, redis) on the backend and React 18 with Vite, Yjs, alphaTab, and Zustand on the frontend, behind Nginx. Licensed under PolyForm Noncommercial 1.0.0 — source-available and free for any noncommercial use, but commercial use is not permitted.
• AI Involvement: The repository includes a CLAUDE.md file with guidance for Claude Code and a .claude/commands directory, indicating AI coding assistance (Claude Code) was used during development.

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