Spring Boot 2.7 to 3.3 on a European bank project: what actually broke (it was not just javax)
Our client, a mid-size bank in Europe, got a finding from their security team: Spring Boot 2.7, open source support ended in November 2023, upgrade. So our team of 7 in Pune got the job. 41 Maven modules, Oracle database, a partner integration in Frankfurt, and a change advisory board that meets once a week. Here is what broke, in the order we found it. 0. Java 17 first, separately Boot 3 needs Java 17. We moved…
- properties-migrator is underrated. And yes, remove it after, I found it in production at two companies.
- The Hibernate sequence one bit us on Oracle too. db_structure_naming_strategy=legacy is the line. Saved this for our next upgrade.