Which one should I pick for a new project?

Based on your use case, here's the breakdown:

Pick realm/realm-java if:

• You're building an Android application that needs a mobile-first database
• You want a lightweight, embedded database (no server required)
• You need simple data persistence with rich querying capabilities
• You're comfortable with Java/Kotlin and the Realm SDK model

However, note the deprecation warning: The README explicitly states that Atlas Device Sync + Realm SDKs were deprecated in September 2024. The documentation recommends using Realm Kotlin instead for new projects, which supports both Android and Kotlin Multiplatform.

Pick yunaiv/yudao-cloud if:

• You're building a backend cloud application (not mobile)
• You need a full enterprise management system with code generation, workflows, and multi-database support
• You want a complete application scaffold with services, controllers, and database schemas already designed
• You're comfortable with Spring Boot and relational databases (PostgreSQL, MySQL, Oracle, DM, KingBase, etc.)

The repos serve entirely different purposes:

• realm/realm-java: Mobile database engine (deprecated for Sync, but core database still usable)
• yunaiv/yudao-cloud: Enterprise backend framework with code generation and workflow engines

For a genuinely new project, if it's mobile, consider Realm Kotlin instead of realm-java. If it's backend, yudao-cloud could provide a working scaffold, but evaluate whether you want to start from a template or build independently.

FOLLOW_UPS:

• Does Realm Kotlin support offline-first sync like realm-java?
• What specific features does yudao-cloud's code generation provide?
• Can yunaiv/yudao-cloud run standalone or require external services?