Multiple versions of a sequential dataset are maintained without storing the full file set for each version. A full file set for the current version is stored, as well as a chain of forward and/or reverse patches between adjacent versions. New content for the dataset is received, and a new current version is built that includes this new content. Patches between the new and immediately previous versions are built and stored. When a request is received from a client for an update to the current version, multiple patches of the chain are merged, from the client version of the dataset to the current version. This merging of patches creates a single direct delta, which comprises all operations for updating the client version to the current version. The direct delta is then transmitted to the client.