The digital twin workspace for Eurorack musicians.

Document patches, plan racks, track modules, and keep your real system in sync with a fast, clean workflow.
patcher.xyz  ·  Discord  ·  Changelog

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New since v5.0

• Instance-aware patching for repeated modules.
• Auto-save for patch state and edits.
• Power analysis and balance analysis in rack detail.
• Multi-panel module support with panel gallery improvements.
• Public profiles, contributor stats, and better discovery tooling.

See the full CHANGELOG for details.

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Feedback & bug reports

Have an idea or found something broken? Come talk to us on Discord — it's the fastest way to reach the team and the right place for feature discussions.

Technical bug reports can also be opened as GitHub issues.

Table of Contents

1. Introduction
2. Why Patcher?
3. User Guide
4. Setting Up the Project Locally
5. Running E2E Tests
6. Project Dependencies
7. Schema Reference
8. Pull Requests
9. License
10. AI & Open Data Stance

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Introduction

Patcher is a free, open-source workspace for Eurorack musicians. It combines patch editing, rack planning, module tracking, and a public hardware database so you can keep a documented record of your setup, ideas, and modules.

The database is currently publicly accessible and free to browse. No paywalls, no account required to explore public content.

Contributions are welcome — whether that's code, module data, or feedback.

Why Patcher?

Patcher is built for the full modular workflow, not just patch notes.

At a glance

• Document your patches, racks, modules, notes, and connection state in one place.
• Plan racks quickly with drag-and-drop placement.
• Move fast with streamlined connection flow and app-wide auto-save.
• Read patch complexity quickly with live stats for cables, modules, and multiples.
• Plan racks with live HP, power, and balance analysis.

Why it stays useful

• Works across desktop, tablet, and mobile browsers, with the richest editing flows on larger screens.
• Public/private controls for patches and racks.
• Free, publicly accessible Eurorack module database with community-contributed specs.
• Modern UX built for everyday use, not just collection storage.

User Guide

👉 Read the User Guide for end-user workflows:

• Module discovery and filtering
• Patch creation, graphs, privacy, and comments
• Rack planning, analysis, and media export
• Profile, account, and public-sharing controls

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Setting Up the Project Locally

Use pnpm for dependency management:

git clone <repository_url>
cd Patcher
pnpm install
pnpm start
# or, when you need to debug SSR-specific behavior:
pnpm start:ssr

Local app URL: http://localhost:5556/

Branches: develop is where active work happens. production is deployed automatically — do not push to it directly.

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Local Supabase Backups

• Inspect the read-only backup commands first: pnpm backup:data:dry-run
• Create a local backup snapshot: pnpm backup:data
• Restore a backup on purpose: pnpm restore:data -- backups/data_YYYY-MM-DD_HH-MM-SS.sql

Notes:

• pnpm backup:data uses local pg_dump as a read-only operation, so it does not write to the remote database.
• Backup uses the linked Supabase project from your authenticated CLI session.
• Install local Postgres client tools first if needed: brew install postgresql@16
• Backup files are written to ./backups/, and that directory is gitignored to avoid committing real database snapshots to this public repository.
• The backup script refuses to run if git is not ignoring backups/.
• Restore is intentionally separate, requires SUPABASE_DB_URL, and asks for explicit confirmation before writing.

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Running E2E Tests

• Public smoke suite: pnpm test:e2e
• Authenticated suite: pnpm test:e2e:auth

For contributor setup (required .env keys, dedicated test account, and why playwright/.auth/ is ignored), see e2e/README.md.

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Project Dependencies

The project uses the following tools and libraries:

Tool/Library	What
Angular	Web framework. Using v21
Angular Material	UI components. Using v21
Supabase	Database, authentication, and storage
Vercel	Deployment, hosting
GitHub	Version control, issue tracking, project management, test automation
Database	PostgreSQL hosted on Supabase
Sentry	Error tracking, performance monitoring, and session replay
Other Dependencies	Check the package.json file

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Schema Reference

Patcher's live schema evolves with the app, so the most reliable references are the generated types and backend registry:

• Generated Supabase types: src/backend/database.types.ts
• Backend table/join registration: src/app/features/backend/DatabaseStrings.ts
• Regenerate types after schema changes with: pnpm updateBackendTypes

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Pull Requests

Open pull requests on GitHub from your fork.

For faster review:

• Keep PRs small and focused.
• Split large changes into multiple PRs when possible.
• Submit foundational changes first, then follow-up work.

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License

This project is licensed under the GNU Affero General Public License v3.0. For more information, see the LICENSE file.

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AI & Open Data Stance

Patcher is intentionally pro-open-data.

Public content on patcher.xyz is meant to be discoverable and reusable, including by AI systems. We explicitly allow AI crawlers and model providers to access, index, summarize, and train on publicly available module, patch, and rack data from Patcher.

We also actively use AI tools in this project ourselves. Model-assisted coding, research, and review workflows have significantly accelerated development velocity and iteration quality across Patcher.

This applies only to content users have marked as public. Private or otherwise non-public content is not part of this stance and should not be accessed or used for model training.

Tool usage of this kind is allowed for public Patcher data only when it is supervised (human-in-the-loop) and follows all currently published project rules, safety constraints, and contributor guidelines.

Crawler guidance lives at https://patcher.xyz/llms.txt and in src/llms.txt.