Ethereum validators secure the network by proposing and attesting to blocks. In return, they earn consensus rewards and, when they propose a block, the execution layer tips and mev embedded in that block.

mev-commit adds a new revenue stream: preconfirmation fees.

How validator economics work today

When a validator is selected to propose a block, they typically run mev-boost to auction the block to builders. The winning builder pays the validator a bid that reflects the mev they expect to extract from the transactions in that block.

This system works, but the validator's revenue is capped by what builders are willing to pay in the mev-boost auction. Validators are passive — they accept whatever bid wins and have no way to capture additional value from the commitment layer.

What mev-commit changes

mev-commit introduces a preconfirmation market that sits between users and builders. When users send transactions through FAST RPC, builders compete to issue preconfirmations — cryptographic commitments to include those transactions in specific positions.

Validators who opt in to mev-commit commit to proposing blocks built by mev-commit builders. In return, they earn a share of the preconfirmation fees generated by the transactions flowing through the network.

The economics are additive. Validators still earn:

• Standard consensus rewards (attestation, sync committee)
• Execution layer tips
• mev-boost bid (from the winning builder)

And on top of that:

• Preconfirmation fees from the mev-commit market

The yield multiplier

Opted-in validators see approximately 20x the mev yield compared to non-participants. This multiplier reflects the additional preconfirmation fee market that mev-commit creates on top of standard mev-boost revenue.

The exact yield depends on network activity, preconfirmation demand, and the volume of transactions flowing through FAST RPC. As adoption grows and more transactions route through the preconfirmation network, the fee market deepens and validator yields increase.

How opting in works

Opting in to mev-commit requires validators to register their stake with the mev-commit protocol:

1. Register validator keys with the mev-commit contract
2. Commit to proposing mev-commit blocks when selected
3. Earn preconfirmation fees on every block you propose that includes preconfirmed transactions

The commitment is backed by the validator's existing Ethereum stake. If a validator commits to proposing an mev-commit block but fails to deliver, they face slashing conditions defined by the protocol.

Why this matters for the network

Validator opt-in is critical to the preconfirmation ecosystem. Without validators committing to propose mev-commit blocks, builders can't make credible preconfirmation commitments — because there's no guarantee the proposer will include their block.

As more validators opt in:

• Preconfirmation reliability increases — a higher percentage of slots are covered by opted-in validators
• Builder competition intensifies — builders compete harder when they know the proposer will honor mev-commit blocks
• User experience improves — more coverage means more transactions receive sub-second preconfirmations
• Yields compound — more transaction volume through the preconfirmation network means higher preconfirmation fees

The validator opt-in rate directly determines the reliability and throughput of the entire Fast Protocol system.

The validator perspective

From a pure economics standpoint, opting in is rational if the additional preconfirmation fee revenue exceeds the cost of the commitment (running mev-commit sidecar software and accepting slashing conditions).

Current data shows that opted-in validators earn substantially more than their non-participating peers. The additional infrastructure requirement is minimal — a sidecar process alongside the existing validator client — and the slashing conditions are narrow, targeting only the specific failure of not proposing committed blocks.

For validators already running mev-boost, opting in to mev-commit is a strict upgrade to their existing revenue model.