The Vouch MEV Stack
MEV (Maximal Extractable Value) is the value available in the ordering of transactions inside a block. On every block someone captures it — the only questions are who captures it and how they behave while doing it.
The Vouch MEV stack is the infrastructure that decides this on PulseChain. It routes block building through an open, competitive auction and sends the value back to the validators, the vPLS community, and everyday users — instead of to extractors.
How it fits together

- A Searcher watches the mempool for profitable opportunities and packages them into bundles.
- A Builder assembles the most valuable block it can from those bundles and the public mempool, and bids for it.
- The MEV-Relay runs a neutral auction: many builders compete, the highest valid bid wins.
- The validator's MEV-Boost sidecar asks the relay for the best block header and the validator signs it.
- The winning builder's payment lands at the validator's registered fee recipient — for Vouch validators that is the ValidatorFeeDepositor (VFD), which flows into the wider ecosystem.
The three components
| Component | What it is | Who it's for | One-liner |
|---|---|---|---|
| MEV-Boost | A lightweight sidecar that runs next to a validator. | Validators | Any validator. Keep your rewards, add the uplift. |
| MEV-Relay | The neutral auction builders bid through. | Builders | Any builder. Open competition for every block. |
| BlockFerret | Vouch's own ethical MEV builder, in alliance with Switch.win. | The Vouch ecosystem | Ethical building. No sandwiches, ever. |
Ethics and neutrality
MEV is unavoidable. Vouch's approach is to make it transparent and fair rather than to censor it:
- The relay stays permissionless and credibly neutral — open to every validator and every builder, with no allowlist and no favourites.
- Our own builder (BlockFerret) is where the ethics live — it captures arbitrage and back-runs, and never sandwiches or front-runs users.
Public transparency
Every payload the relay delivers is publicly visible. Anyone can audit the flow at the delivered-blocks explorer.
Where do you fit in?
- I'm a validator and want more from my proposals → MEV-Boost (Validators)
- I'm a builder / searcher and want to bid for blockspace → MEV-Relay (Builders)
- I want to understand Vouch's own builder → BlockFerret