Which one should I pick for a new project?

Based on the repository data and their purposes, here's what you should consider:

realm/realm-java — Choose this if:

• You're building an Android mobile app that needs local data persistence
• You want a mobile-first database designed to run directly on phones/tablets
• You need features like thread-safety, encryption, and relationships without ORM complexity
• You prefer a simple API with minimal classes to learn

The README states it's "a mobile database that runs directly inside phones, tablets or wearables" and is "faster than even raw SQLite on common operations."

Important caveat: The repository includes a deprecation warning at the top of the README — Atlas Device Sync and Realm SDKs were deprecated in September 2024. For new projects, MongoDB recommends the Realm Kotlin SDK instead (available at https://github.com/realm/realm-kotlin), which is now GA and supports both Android and Kotlin Multiplatform.

yunaiv/ruoyi-vue-pro — Choose this if:

• You're building a full-stack web application (Java backend + Vue.js frontend)
• You need a business management system with admin dashboard, code generation, and data configuration
• You want a template/scaffold for rapid CRUD application development
• Your focus is server-side Java with a modern web UI

This is a complete business application framework, not a database library.

Bottom line: Pick Realm Kotlin for new Android projects (not realm-java). Pick ruoyi-vue-pro only if you need a full backend+frontend business app scaffold.

FOLLOW_UPS:

• What type of application are you building?
• Do you need offline-first data sync?
• Is this a mobile or web backend project?