What are the "Killer Features" Hidden in Ethereum's Glamsterdam Upgrade, Strongly Promoted by Vitalik?

Ethereum founder Vitalik Buterin has been quite active on social media lately, first reflecting on the previous direction of Layer 2, and then outlining new plans for Ethereum's future roadmap.

This has raised more expectations for the upcoming Ethereum Glamsterdam upgrade in the first half of this year. What are the key components of Glamsterdam, the most significant update for Ethereum in the first half of this year?

Understanding the "Current" by Looking at the "Previous"

Before understanding Glamsterdam, we need to understand its "predecessor" – the Fusaka upgrade.

Fusaka was a data layer upgrade for Ethereum. It introduced two key features: PeerDAS and EOF.

PeerDAS: Instead of downloading all the data, you only need to download a small portion. It's like sampling; you don't need to ask everyone, just a small group to infer the situation of the entire population. Combined with ZK proofs, even if only 1/16 of the total data is downloaded, data integrity can be confirmed, significantly improving Ethereum's network throughput.

EOF: This can be understood as an internal reform of the EVM. It makes the EVM's code structure clearer, more modular, and easier to optimize. EOF is like "renovating" the EVM, making its internal structure more rational.

If Fusaka was a "data layer upgrade," then Glamsterdam is an "execution layer upgrade." Fusaka primarily addressed "how to transmit data," while Glamsterdam aims to solve "who produces blocks."

The Core of Glamsterdam – ePBS and BAL

ePBS separates the block packaging and validation processes – block builders are responsible for packaging transactions, proposers for proposing blocks, and validators for validating blocks. Each role performs its own duties. If everyone does their part well, block builders can be more aggressive in packing more transactions because proposers and validators will check for them, reducing security concerns.

Can't Ethereum do this now? It can, but it relies on relays like Flashbots to separate "proposing" and "building." Validators are only responsible for "proposing blocks," while builders package transactions to earn MEV (Maximal Extractable Value).

This creates a black box, and the consequence of having to trust third-party relays can lead to failures, censorship, attacks, or centralization.

ePBS formalizes this separation-of-powers mechanism into a protocol-native feature (EIP-7732), turning it into an "on-chain auction + protocol enforcement," solving trust issues and improving network efficiency.

The Block Access List (BAL) allows block packagers to inform validators in advance: "The transactions in this block will access these accounts and storage locations." With this information, validators can prepare in advance, loading this data from disk to memory. Then, validators can check multiple transactions in parallel instead of one by one. It's like an assembly line in a factory: previously, one worker handled the entire product; now, multiple workers process different parts simultaneously.

The combination of these two creates a dual reinforcement – efficiency improvement and censorship resistance.

However, for ePBS to achieve its full potential, another piece of the puzzle is needed – the Fork-Choice-Enforced Inclusion List (FOCIL). FOCIL allows validators to publish a "must-include" transaction list. If a builder does not include these transactions, validators can reject the block through fork-choice rules. This gives validators a "last line of defense" to prevent builders from excessive censorship.

However, launching ePBS and FOCIL simultaneously would be highly complex. Therefore, the arrival of FOCIL will have to wait for the second upgrade this year, Hegotá.

Potential Impact of Glamsterdam

In addition to ePBS and BAL, Gas fee repricing + multi-dimensional Gas will also be included in the Glamsterdam upgrade. This will make transactions cheaper for ordinary users and further increase the network's overall capacity, but at the cost of higher fees for some developers (those needing to build new states).

For stakers, the revenue model becomes clearer, block selection power increases, and MEV rewards become smoother. This also means the MEV ecosystem will change, and some applications that rely on existing methods to earn MEV may need to adjust.

As validator power increases, new application opportunities will emerge. For example, new "validator service" applications might appear to help validators better select blocks.

But the Glamsterdam upgrade is certainly not perfect. As mentioned earlier, while ePBS will arrive with the upgrade, it will be an incomplete version without FOCIL. The complexity of this update is quite high, and it gives more power to validators. Besides post-launch stability, whether decentralization leads to new forms of centralization at the validator level is also worth watching.

Vitalik also admitted, "ePBS only prevents builder centralization from spreading to the staking layer, but the problem of block builder centralization itself remains." Toxic MEV (sandwich attacks, front-running) might just "move elsewhere" and continue to exist.

However, in the long run, the greatest significance of the Glamsterdam upgrade might be "decentralization." Vitalik's persistence and idealism regarding decentralization theory might make traditional finance and the world trust Ethereum's adoption more. Time may provide the true answer to this persistence in Ethereum's price.

Since last year, Ethereum's major updates have increased to twice a year. No longer complacent, Ethereum, now "racing against time," might truly regain its former glory.