Preparing for Your Next Spring Boot Migration

The Challenge

Spring Boot 4 is here — but most organizations are still running earlier versions like 2.x or 3.x across large, distributed codebases. That’s normal. Version drift happens, and it compounds over time. The good news: whether your next upgrade is 2.x → 3.5 or 3.5 → 4.0, the preparation steps are the same — and they’re the key to making any Spring Boot migration predictable and low-risk.

Why Attend

In this hands-on training, you’ll learn how to prepare your codebase using a staged, practical workflow used by modern platform and application teams. We’ll walk through how to inventory your services, find deprecated patterns, and uncover hidden friction using semantic search and essential OpenRewrite recipes like DependencyInsight and FindDeprecatedUses.

Then we’ll cover the incremental upgrades you can safely merge now, long before a major migration: moving to JUnit 6, adopting JSpecify, aligning on Java 17/21/25, modernizing Spring Security configuration, and upgrading to Spring Boot 3.5.x — the release that introduces replacements for APIs removed in future versions.

You’ll walk away with a clear, repeatable process for preparing your organization for any Spring Boot migration, whether you’re catching up or planning ahead.

What You'll Learn

• How to build a version inventory and identify migration hotspots, and order of services to migrate
• How to use DependencyInsight, FindDeprecatedUses, and semantic search to surface risk
• The recommended sequence for JUnit, Java, JSpecify, and Spring Boot 3.5.x upgrades
• How to reduce friction and shorten the timeline of your next Spring Boot migration