Synchronizing a client and server version of a hierarchical data structure having several atomically-editable components. At synchronization time, the server identifies all of the changes that need to occur to the client version in order to properly synchronize the client version of the hierarchical document with the server version. Each of the changes involves edits of one or more of the atomically-editable components of the data structure. The server fragments the synchronization information into multiple messages, and then individually sends the message to the client computing system. The client atomically processes each of the messages. For each change to be made as identified within a single message, the client computing system identifies the atomically-editable components that are involved by the change, and then edits (e.g., inserts, changes, or deletes) the atomically-editable components in a specified manner.