So, I set up a way to fetch the latest stuff from the server by just grabbing the last N items from the collection. But then I thought of a cooler way to sync things. If your context collection has actions that change things (like Add or Remove), the client can rebuild the current state by getting these actions in reverse order and applying them one by one. You don’t even need to mess with digests—just keep track of the latest activity ID and you’re good to go.