Add Jackson 3 support

[dpishchukhin]

I'd be great to have a new module that is compatible with Jackson 3 API.

[Camsteack]

Hi ! Is there any plan to add support for Jackson 3 ? This is blocking our upgrade at the moment :)

[komamitsu]

Thanks for the request. Unfortunately, I’m not planning to add Jackson 3 support at this time.

Jackson 3 changed its package names from com.fasterxml.jackson.* to tools.jackson.*. As a result, supporting both Jackson 2 and 3 requires us to duplicate the entire implementation and maintaining two parallel code paths. In addition, Jackson 3 requires Java 17 or later, while msgpack-java currently supports Java 8.

Jackson 2.18 is an LTS release and will continue to be maintained alongside Jackson 3, so it remains a viable and supported option for users of this project.

I’ll keep this issue open to track interest, but at the moment the maintenance cost outweighs the benefits.

Regarding the upgrade concern: since Jackson 3 uses a different package prefix from Jackson 2, it is technically possible to use both Jackson 2 and Jackson 3 in the same library or application without conflicts. Even if jackson-dataformat-msgpack depends on Jackson 2, that should not inherently block adopting Jackson 3 elsewhere.

[prdoyle]

Have you considered the tip-and-tail model suggested by the JDK folks? Move to the latest of everything on the main branch, and maintain a "tail branch" with only bug fixes for older Java/Jackson versions?

[magicprinc]

Spring Boot 3 is EOL JUL 2026!😱

Spring Boot 4 uses Jackson 3 by default.

So it's time to move to Jackson 3 🙏

[komamitsu]

I am currently busy with Wormhole4j. I will look into this issue after the new version of Wormhole4j is released.