<a class="mention" href="/@elas_digital">@elas_digital</a> I think at the time I was thinking about ways in which we could make conditional payments based on tokens. That is, pay token A to X and then other tokens or BSV are able to be spend by Y. It is definitely doable in Script if we don&#39;t have backtracking. Ethereum does this by having a shared state that every transaction can modify via. That way conditionals are simple as making a contract that says (if token A is being sent to X, update memory to state Q) and later (if memory is at state Q is send token B to Y). This is part of the reason why it&#39;s unscalable, all transactions and contracts can modify the same state, and the main motivation behind sharding. On Bitcoin, assuming we don&#39;t have backtracking for tokens, it would be as simple as adding requirements to the OP_PUSH_TX preimage. For example, we can assert that an input being spent has a ScriptPubKey of Token A and that one of the outputs allow BSV or tokens to be spent by Y. At that point you have all the benefits of Ethereum with the scalability of Bitcoin.