I use a plugin called FeedManager which allows me to publish my product feeds to a multiplicity of different shopping engines. http://www.foxnetsoft.com/nopfeedmanager
The developer is adding support for new feeds all the time, so I think he will add support for jet.com if you ask him. When you ask him to add support for jet.com, give him this link: https://developer.jet.com/v1.02/docs