Todays dapp-a-day, a ForkableDatastoreService provides a set of virtual storage spaces ("datastores") which can be forked. Forking a datastore creates an exact copy at the time of the fork. This is achieved with a copy-on-write virtualization strategy, which means that the cost is amortized over all storage slot updates. A consequence of this cost structure is that fork must somehow be managed: it can only be called by the branch's owner, the address which can also set the branch's entries. The forking DB tracks number of slots on each branch, so it can fully clean up after itself and owners can invent reasonable forking rules.
https://github.com/nexusdev/ds-forkable
Roadmap
ds-token.