Rule Makers in the Blockchain Ecosystem: Analyzing the Key Role of Block Builders

In the world of Blockchain, code is law. At the foundational level of this world, Block builders play a crucial role. They determine the success or failure of the Blockchain, because if there are issues with Block production or deviations in the incentive mechanisms, the integrity of the entire system will be threatened.

Block builders are responsible for selecting transactions from the memory pool and assembling them into blocks, which are then propagated through the network to achieve consensus. The design of the building process varies across different blockchain platforms. For example, on Ethereum, a well-known project dominates; while on other platforms, different projects are in the lead.

The core issue that these projects aim to solve is known as "maximum extractable value" ( MEV ). Simply put, participants responsible for ordering transactions tend to maximize their own profits, which may lead to them maliciously reordering transactions, thereby increasing user costs.

To address this challenge, some projects have proposed the concept of miner-extractable value auction infrastructure (MEVA). The design goals of MEVA include stabilizing gas fees, promoting competition, and controlling centralization. This is mainly achieved by adjusting the incentive mechanisms: if participants can receive economic compensation for increasing positive externalities or reducing negative externalities, they will naturally do so.

However, achieving this balance is not an easy task. Taking Ethereum as an example, its block time of about 12 seconds gives all participants enough time to simulate and optimize transaction ordering. The proposer-builder separation (PBS) model currently adopted by Ethereum divides the process into five roles: users, Block producers, relayers, Block proposers, and seekers. This design aims to promote competitive Block construction by decentralizing interests while ensuring the profitability of the Blocks.

However, this model also faces challenges. Block production has become somewhat centralized, with the top builders holding more than half of the market share. In addition, some applications have begun to participate in the transaction sorting process through their own mechanisms, thereby reclaiming some of the value that originally flowed to the block proposers.

With the emergence of a new generation of high-performance Blockchain, MEVA faces new challenges and opportunities. These new platforms often adopt innovative architectural designs, such as the separation of the execution layer and the consensus layer, to achieve higher transaction processing speeds and shorter block times. However, this also brings new issues, such as state uncertainty, limited block simulation time windows, and execution uncertainty.

In the face of these challenges, industry experts are working hard to design solutions that can ensure a low transaction failure rate while also ensuring profitability for block builders. With the launch of the testnet, we look forward to seeing more innovative MEVA design solutions and their performance in practical applications.

In the future, the development of MEVA will continue to be a key topic in the blockchain ecosystem. It is not only about technical implementation but also about how to find a balance between efficiency, fairness, and decentralization. With the addition of more innovative projects, we have reason to believe that the blockchain world will move towards a more efficient, fair, and sustainable direction.