Aestus: A Neutral Relay

We would like to introduce the Aestus MEV-Boost relay, which is currently undergoing testing for a mainnet launch. This project developed out of conversations between members of the reddit EthFinance and EthStaker communities who see the need to develop credibly neutral architecture for the Ethereum staking ecosystem. The primary contributors to this project are myself and KuDeTa, both active members of the previously mentioned communities.

The Aestus relay is MEV infrastructure which we offer to the community as a public good, free from any commercial interest and aligned to principles of credible neutrality:

  • Censorship resistant: Any relays or other architecture will never censor or filter transactions,
  • Non-judgmental: Will never exclude or promote specific types of MEV searcher strategy,
  • Non-profit: Will never profit indirectly or directly from MEV,
  • Unbiased: Will never compete with or make exclusive relationships with builders and searchers,
  • Open source: Our architecture and all modifications to existing projects will be published for all to see.

The Aestus relay is running a fork of the Flashbots MEV-Boost Relay stack. This includes Flashbots’ mev-boost-relay, block-validation-geth, and prio-load-balancer. The relay is deployed on a Kubernetes cluster, with our own open-sourced configuration providing scalability and redundancy. We are currently running naive builders on Goerli and mainnet for testing purposes only. As things stand, we’re hosting this in a single region (East Coast USA) -but will explore multi-region options as we attract builders.

Our Goerli relay has been operating for a month and produced a number of block proposals. Our mainnet relay is also live, and we are looking to subject it to more rigorous testing before we announce it for general use. In particular, we need experienced validators and builders who understand the risks to connect to both networks’ relays.

Additionally, if anyone has experience in testing relay architecture (e.g. simulating high traffic or testing block simulation) or in devops (particularly kubernetes config) and is able to make a consistent donation of time and effort, please do get in touch.

Note: Our main homepage is currently blocked by MetaMask’s highly-aggressive fuzzy-matching filters (it’s vaguely similar to a website domain name that was previously associated with scams - that’s all). When you see the anti-phishing page, don’t freak out. We’re waiting on our allowlist request, but subdomains such as and all builder/proposer API calls are still accessible.


Apparently this forum doesn’t allow new users to have more than two links in one post. So in addition to the main relay links in the above post, here is a link to our GitHub org with our forks of the Flashbots relay and our kubernetes configuration. We are currently running Flashbots’ prio-load-balancer and boost-geth-builder with no significant changes, those can be found in the Flashbots GitHub org.

1 Like

Hey all, a follow-up on the Aestus relay. After plenty of testing on Goerli and mainnet, we’re ready to announce the official launch of the mainnet relay!

The previously mentioned MetaMask filtering issue has been resolved, and the website is fully accessible. The relay has produced a steady stream of block proposals over the last few days. These are all blocks built by our test builder, which does not employ any searcher strategies, so we appreciate the validators who have proposed our blocks. At this point we feel confident in the relay’s reliability.

Moving ahead, one of the most important next steps is to connect with third-party builders. Once we are reliably connected to external builders, we will permanently decommission our test builder to limit the trust assumptions we require. If you are a block builder, please get in touch if there’s anything we can do to get you onboarded. We also welcome relay monitors to track Aestus performance and block production. We will do what we can to improve our transparency and make monitoring easy; please reach out if we can help with this.

We have a full announcement on Medium, and you can always visit our website.