🤖 AI Summary
Existing blockchain smart contracts lack a transaction ordering mechanism that simultaneously balances expressiveness and block production efficiency. This work proposes a monotonic priority system that enables developers to assign integer-valued global priorities to function calls, subject to the constraint that a call’s priority must not exceed that of any call it depends on. Block builders then sequence transactions in non-increasing order of priority. For the first time, this study formally derives a contract-specific transaction ordering rule as the unique solution satisfying five independent axioms. The resulting framework guarantees both high expressiveness and tractability, offering a theoretically rigorous yet practical foundation for transaction ordering in blockchain systems.
📝 Abstract
Modern blockchain applications benefit from the ability to specify sequencing constraints on the transactions that interact with them. This paper proposes a principled and axiomatically justified way of adding sequencing constraints on smart contract function calls that balances expressivity with the tractability of block production. Specifically, we propose a system in which contract developers are allowed to set an integer global priority for each of their calls, so long as that the call's chosen priority is no higher than the priority of any of its referenced calls. Block builders must then simply sequence transactions in priority order (from high to low priority), breaking ties however they would like. We show that this system is the unique system that satisfies five independent axioms.