To design relational database schemas visually and generate production-ready SQL migrations without writing boilerplate DDL by hand, developers use StackRender, an interactive browser-based schema modeling studio. Users can start from a blank drag-and-drop Entity Relationship Diagram canvas or import existing SQL DDL scripts directly from PostgreSQL, MySQL, MariaDB, SQLite, Oracle, and Microsoft SQL Server databases. Each table node provides granular control over column data types, lengths, precision, character sets, collations, nullability, uniqueness, primary keys, composite indexes, and custom PostgreSQL enum types. When connecting tables across one-to-one, one-to-many, and many-to-many relationships, the schema analyzer checks for circular foreign key dependencies and suggests performance indexes on frequently joined columns. As a schema evolves over time, the visual state-diff engine records every structural modification and generates paired UP forward-migration and DOWN rollback scripts, accurately translating table and column renames into non-destructive ALTER statements rather than dropping and recreating data. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. AGPL-3.0 licensed.