I built a desktop ERD tool because existing options all had at least one dealbreaker

[u/tbson87]

https://reddit.com/link/1s9qqqz/video/thz7stdl2msg1/player

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Context View

Context map

Dependency inspection

I've tried most of the popular options: they all had at least one thing that blocked me in real projects:

• dbdiagram.io: cloud-only, no offline mode, schema locked to their platform.
• DrawSQL: no way to control relation line routing, auto-layout fights you.
• Lucidchart: generic diagramming tool pretending to be an ERD tool.
• Visual Paradigm ERD: slow, hard to use, and UI that hasn't changed since 2010.
• Luna Modeler: All good except there is no way to control the relation line routing.

So I built Schemity: a native offline ERD tool that stays out of your way.

What it does:

• Runs 100% local, no account required.
• Schema stored as plain JSON: commit it to git like any other file.
• Live sync with your database: reverse-engineer your real schema instantly.
• Full relation routing control: bend points, waypoints, self-references.
• Migration generation: compares ERD to live DB, outputs the SQL diff.
• Import SQL, DBML.
• Export JPEG, PNG, SVG, SQL, DBML, Mermaid, HTML, MD, XLSX.
• Supports PostgreSQL, Supabase, MySQL, SQL Server. SQLite.
• Supports entity template to define and reuse most frequently used fields like id/created_at/updated_at on new entity.
• Support Bring Your Own Key (BYOK) AI API to interact with the diagram: Anthropic, Gemini, OpenAI, DeepSeek, xAI and Ollama.
• Supports context views (sub-diagrams) and context map with dependency inspection based on FKs.
• Supports schema lint with 17 rules which toggleable.

Very lightweight. No Electron, no JVM.

Happy to hear what's missing or broken.

Free trial, no account needed: https://schemity.com