Point-and-click schemas for MySQL, PostgreSQL and SQLite
Thoth Blueprint is a database schema editor that runs in the browser. You place tables, columns, indexes and relationships on a canvas with the mouse, targeting MySQL, PostgreSQL or SQLite. A diagram can start empty or from an existing schema imported as SQL DDL, DBML or JSON. On the way out, the tool writes SQL for the chosen engine and migration files for a Laravel, TypeORM or Django project.
Framework migrations and a DBML tab that writes back to the canvas
- Laravel, TypeORM and Django migrations each download as a ZIP, and the Django archive includes the models as well. A checkbox in the export dialog leaves foreign key constraints out of the SQL, the DBML and the migrations.
- The DBML tab shows the schema as text, and saving an edit there updates the diagram.
- JSON and Mermaid are the other text exports; SVG and PNG cover images.
- The index manager creates and edits unique and composite indexes and keeps track of column order.
- Checkpoints snapshot the diagram so you can roll back. Since 0.0.10, new projects take one automatically every five minutes.
- An AI assistant can add, change or delete tables, columns, indexes and relationships. It runs on your own Gemini or OpenRouter key, or on a local model served by Ollama or LM Studio. Every change it proposes is checked against a Zod schema and tried on a copy of the diagram before being applied in one step. When a change is rejected, the validation error goes back to the assistant so it can fix the patch.
IndexedDB storage and a canvas that struggles with large schemas
Diagrams are stored in the browser's IndexedDB. The app is a static site: the repository's Dockerfile builds it and serves it with Nginx, and since 0.0.12 each release ships a ZIP that runs under python -m http.server without Node.js. The notes in that ZIP warn that clearing browser data wipes the diagrams. Backups are manual: a .thot file, plain JSON, that holds the diagrams and the assistant chat history. AI provider keys stay in the browser as well, encrypted and unlocked with a passphrase.
The maintainer reports lag at a few hundred tables. Issue #47, which the maintainer opened in April 2026, explains that importing a large database makes the editor sluggish, because xyflow's DOM rendering ends up with 20,000 to 30,000 elements. The fix proposed there is a custom WebGL renderer in place of xyflow, and the issue is still open.
Three engines, with SQL Server marked "coming soon". SQLite joined MySQL and PostgreSQL in 0.0.13; the import dialog lists SQL Server as not yet available. For MariaDB, SQL Server or Oracle, drawDB, another in-browser schema editor, already has those dialects in its engine list.
Generated migrations are drafts to review. The repository's code generation guide says no test runner checks the generated SQL, and tells contributors not to describe a migration as executable before it has been reviewed or run. Django output uses yourapp as the app name. CI covers type checking, linting and a production build.
Latest release: 0.0.13, published on 12 August 2026. Twelve releases have shipped since 0.0.1 in September 2025, and nothing has been committed since 12 August. Of the 418 commits GitHub credits to listed contributors, 406 come from the maintainer, AHS12. The code is licensed GPL-3.0.