Apply this only when the user explicitly asks to migrate Spring Boot 3.x to 4 (or to fix failures caused by that migration). Editing the Boot version in a build file is not enough. Patch bumps within 3.x and 4.0 to 4.1 upgrades are not covered; follow the target Spring Boot version's release notes and upgrade guide for those, not the JDK-focused java-upgrade skill.
For a 3.x to 4 migration, use the spring-boot-4-migration skill. It holds the full workflow and topic references (starters, Jackson 3, testing, configuration properties, removed APIs) for Maven and Gradle.
- Detect the current Boot version first and migrate to the latest 3.5.x before moving to 4.0.
- Run the build and tests after each migration step.
- Never read or print secrets such as
.envfiles.
Get the skill from this repository: https://github.com/github/awesome-copilot/tree/main/skills/spring-boot-4-migration (install it with the GitHub Copilot CLI plugin marketplace or copy the folder to .github/skills/spring-boot-4-migration).