Micronaut Data Guidelines

Apply Micronaut Data patterns for relational repositories and safe SQL.

What is covered in this Skill?

• @MappedEntity, @Id, @GeneratedValue, @MappedProperty for column mapping
• @Repository interfaces extending CrudRepository / PageableRepository
• Derived finder methods and @Query with named parameters
• @Transactional on @Singleton services (readOnly where appropriate)
• Page and Pageable for list endpoints
• DTO/interface projections for read-heavy queries
• @Version for optimistic locking
• Integration tests: @MicronautTest + TestPropertyProvider + Testcontainers

Scope: Apply recommendations based on the reference rules and good/bad code examples.

Constraints

Compile before persistence changes; verify the full build after.

• MANDATORY: Run ./mvnw compile or mvn compile before applying any change
• SAFETY: If compilation fails, stop immediately
• VERIFY: Run ./mvnw clean verify or mvn clean verify after applying improvements
• BEFORE APPLYING: Read the reference for detailed rules and examples

When to use this skill

• Review or implement Micronaut Data repositories and entities
• Add transactions, pagination, or projections in Micronaut persistence layer

Reference

For detailed guidance, examples, and constraints, see references/512-frameworks-micronaut-data.md.