Odaily Planet Daily reports that Ethereum co-founder Vitalik Buterin has recently published a series of technical articles discussing Ethereum’s future roadmap. In his latest article, he analyzes potential centralization risks in the block building pipeline and proposes solutions such as expanding the FOCIL mechanism and introducing encrypted mempools to enhance the network’s censorship resistance.
As planned, Ethereum will introduce the Glamsterdam upgrade in the first half of 2026, which will implement the enshrined Proposer-Builder Separation (ePBS) mechanism. This mechanism allows block proposers to outsource block construction to a permissionless open market, reducing centralization risks at the staking level.
However, Buterin noted that while ePBS can prevent the concentration of block construction rights among a few staking pools, block construction itself may still become concentrated among a small number of advanced participants due to specialization and the pursuit of maximum MEV, leading to new centralization trends.
To address this issue, Ethereum developers plan to introduce the FOCIL (Forward Obligatory Commitment to Inclusion Lists) mechanism alongside the Glamsterdam upgrade. The initial version will randomly select 16 validators to enforce that specific transactions must be included in blocks; otherwise, the blocks will be rejected. Buterin stated that even if block construction is controlled by a single malicious entity, FOCIL can still ensure transactions cannot be fully censored.
In addition, Buterin explored scaling up FOCIL (“big FOCIL”) and introducing an encrypted mempool to further reduce information asymmetry and centralization of power in the block building process.
Recently, Buterin has been actively speaking on topics such as quantum resistance roadmaps, execution layer improvements, and block building mechanisms, indicating that Ethereum’s core development team is systematically designing and assessing risks for the next phase of protocol upgrades.