1) Do something like this (check if optaplanner-persistence-jackson jar is already in the classpath) in the JacksonMarshaller

        ObjectMapper objectMapper = new ObjectMapper();
        objectMapper.registerModule(OptaPlannerJacksonModule.createModule());

2) Also evaluate the impact of removing ScoreWrapper in favor of just Score:
https://github.com/kiegroup/droolsjbpm-integration/search?utf8=%E2%9C%93&q=ScoreWrapper&type=
Create a separate jira if it's possible. Note that it might impact XStream, JAXB and Jackson. Will it affect backwards compatibility? Does the optaplanner-xstream/jaxb implementation have a way to deal with just Score fields (so not HardSoftScore fields)?