# Kotlin Conventions

## Language Features
- Use Kotlin 2.x with coroutines for async work
- Prefer data classes for DTOs and value objects
- Use sealed classes/interfaces for domain errors
- Extension functions over utility classes

## Spring Boot
- Constructor injection (no field injection)
- Use @ConfigurationProperties over @Value
- Prefer WebFlux for reactive endpoints
- Use Spring Security with method-level security

## Testing
- JUnit 5 with Kotest assertions
- MockK for mocking (not Mockito)
- Testcontainers for integration tests
- Use @Nested for test organization

---
trigger: glob
globs: "**/*.test.ts"
---

# Testing Conventions

- Use Vitest as the test runner
- Colocate test files next to source files
- Use describe blocks organized by function/component name
- Prefer userEvent over fireEvent in component tests
- Mock external services; never hit real APIs in unit tests