Jackson on 1Stophttps://blogs.rameskum.com/tags/jackson/Recent content in Jackson on 1Stop1Stophttps://blogs.rameskum.com/images/og-default.pnghttps://blogs.rameskum.com/images/og-default.pngHugoen-usSat, 10 Oct 2026 11:00:00 -0400Jackson 3 Is the Migration Inside Your Spring Boot 4 Migrationhttps://blogs.rameskum.com/posts/jackson-3-migration-spring-boot-4/Sat, 10 Oct 2026 11:00:00 -0400https://blogs.rameskum.com/posts/jackson-3-migration-spring-boot-4/Spring Boot 4 quietly switched the default JSON engine to Jackson 3: new tools.jackson namespace, JsonMapper replacing ObjectMapper, immutable mappers, and unchecked exceptions. Your old Jackson 2 config bean silently stops applying. This is the before/after migration guide — namespace, builder API, custom serializers, and the order to do it in.