Even though I don&#x27;t use Meteor anymore, I still like DDP[1] a lot. It&#x27;s simple (can be implemented in 50-100 lines), but it is the core of Meteor. There&#x27;s a specification for it in their Github repo. Meteor&#x27;s &quot;optimistic UI&quot; is basically an abstraction on top DDP, IMO.<p>[1] <a href="https:&#x2F;&#x2F;www.meteor.com&#x2F;ddp" rel="nofollow">https:&#x2F;&#x2F;www.meteor.com&#x2F;ddp</a>