Upgrading a Spring Boot application from Java 8 to Java 17 is more than a version bump—it’s a critical step toward leveraging modern Java features, improved performance, and long-term support (LTS). However, it also comes with challenges like breaking changes, dependency compatibility, and new language semantics. In this guide, we’ll focus deeply on the essential steps you need to take, explaining each in detail to ensure a smooth transition without compromising your application’s stability.