private JsonNode serializeWithoutHeaders(IVersionedApimanEvent apimanEvent) {
        // Ignore #getHeaders as we're packing that in manually in #onEvent.
        OM.addMixIn(apimanEvent.getClass(), IgnoreHeadersMixin.class);
        return OM.valueToTree(apimanEvent);
    }
Enable the outbox. Any events received whilst will <strong>will</strong> be inserted.
<p>
The outbox is enabled by default.
manager/api/jpa/src/main/java/io/apiman/manager/api/jpa/model/outbox/TransactionalOutboxService.java