Spring Boot Testing & Migration

About

This skill equips Claude with specialized knowledge to navigate the significant testing changes introduced in Spring Boot 4, specifically the required migration from @MockBean to @MockitoBean. It provides expert guidance on selecting the right test slice (WebMvc, DataJpa, Json) to maximize test speed, implementing Testcontainers with the simplified @ServiceConnection API, and performing advanced verification with Spring Modulith's Scenario API. Whether you are upgrading a legacy suite or building a new reactive backend, this skill ensures your tests are idiomatic, secure, and maintainable.

Key Features

• Security testing implementation with @WithMockUser and JWT mocking
• Optimized slice testing configurations for Web, JPA, and REST clients
• Simplified Testcontainers setup using @ServiceConnection
• Automated migration patterns for @MockitoBean and @MockitoSpyBean
• 3 GitHub stars
• Spring Modulith event verification using the Scenario API

Use Cases

• Implementing fast, isolated slice tests to improve CI/CD pipeline performance
• Configuring automated integration tests with real databases using Testcontainers
• Upgrading Spring Boot 3.x test suites to Spring Boot 4.x standards