ER Flow for Ruby on Rails Developers

Visual schema design that speaks Rails conventions

Rails developers iterate fast — and schemas drift just as fast. ER Flow gives Rails teams a shared visual canvas to design, review, and document the database before running rails db:migrate. Import your schema.rb to instantly visualize an existing Rails app, then design new migrations with confidence using the visual diff.

Benefits

SQL import converts schema.rb output into a full visual ER diagram in seconds
Checkpoint-based diffing shows exactly what changed so you know what your next migration must contain
Design polymorphic association tables and STI structures visually to catch mistakes before code review
Real-time collaboration means Rails teams review schema changes together before the migration is written
Supports PostgreSQL, MySQL, and SQLite — all three databases used by Rails apps in production
AI via MCP Server lets you describe a Rails resource and scaffold its full schema automatically

How It Works

1

Import

Run rails db:schema:dump and paste the SQL output into ER Flow. Every table and index appears on the canvas instantly.

2

Design

Add new tables for upcoming features. Draw foreign key relationships and define indexes visually.

3

Checkpoint

Save a checkpoint of the current schema as your baseline before making further changes.

4

Diff

Make your schema changes. ER Flow diffs from the checkpoint and shows every added, modified, and dropped column.

5

Migrate

Generate the SQL migration, translate it to Rails migration DSL, and run rails db:migrate.

Import your Rails schema and start designing

Free to get started. No credit card required.

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