BuilderNet

• Name: BuilderNet
• URL: https://buildernet.org/
• Category: decentralized block-building network / TEE-based orderflow-sharing infrastructure / MEV-redistribution control plane
• Tags: ethereum-ecosystem
• Summary: BuilderNet is best understood as a multioperator block-building control plane rather than as just another Flashbots product page or a single builder instance. Its official materials describe a network where multiple operators run open-source builder nodes inside trusted execution environments, share orderflow across peers, submit bids to MEV-Boost relays, and then redistribute MEV back to orderflow contributors through an explicit refund pipeline. The reusable mechanism insight is that BuilderNet tries to move block building away from exclusive bilateral orderflow deals and toward a shared builder network, but today it still relies on central coordination surfaces such as BuilderHub, the Redistribution Archive, and permissioned operator admission.
• What it does:
  • Lets multiple operators run the same Ethereum block-building stack inside TEEs rather than confining block building to a single vertically integrated firm
  • Accepts encrypted orderflow from users, wallets, searchers, and apps either through Flashbots surfaces or directly through BuilderNet endpoints
  • Shares received orderflow across builder nodes in the network so participating operators can collaborate on the same builder flow
  • Uses attested TLS and published TEE measurements so advanced users can verify that a node is running the expected code and configuration before sending orderflow
  • Archives orderflow and bids in a Redistribution Archive to calculate how much value individual transactions contributed and to support MEV refunds
  • Exposes refund APIs and request-signature rules so bundle senders and related orderflow sources can query or redirect fee refunds
• Key claims:
  • BuilderNet’s launch post says the first release introduces a “multioperator” system where many parties can operate the same block builder for the first time, with each operator running an open-source builder in a TEE and sharing orderflow across the network
  • The same post explicitly frames BuilderNet as an alternative to exclusive orderflow deals, aiming to neutralize opaque side deals and turn block building into a more positive-sum shared infrastructure layer
  • The docs say Flashbots Protect and Flashbots Bundle Relay orderflow is automatically shared with BuilderNet, which means BuilderNet is not merely a standalone endpoint but an increasingly central orderflow aggregation surface inside the Flashbots stack
  • The architecture and Flashbots-infra docs show the real control plane still includes BuilderHub for builder identity, provisioning, peer discovery, and configuration plus a Redistribution Archive for refund accounting, so decentralization is partial rather than complete at this stage
  • The docs say builder nodes generate local TLS certificates whose private keys remain inside the TEE instance and can be verified over an attested channel, making confidentiality and machine-verifiability part of the mechanism rather than just an ops detail
  • The launch post says operators can choose different compliance policies, which matters analytically because BuilderNet’s censorship-resistance story depends on multioperator diversity rather than on one operator becoming neutral by assumption
  • BuilderNet’s current refund APIs and refund-rule framing make it useful as a comparison class for systems where orderflow contributors reclaim part of execution value instead of leaving block-building rents entirely with builders or validators
  • The most important governance caveat is that operator entry is still permissioned and key infrastructure remains centralized at launch, so the interesting question is not whether BuilderNet is already decentralized, but which coordination surfaces it is progressively trying to unbundle
• Whitepaper: No canonical standalone BuilderNet whitepaper or litepaper surfaced in this pass. The clearest current sources of truth were the BuilderNet launch post, architecture and API docs, the orderflow-encryption docs, and the BuilderHub repository materials; see ../whitepapers/buildernet-primary-sources-2026-05-10.md.
• Sources:
  • https://buildernet.org/
  • https://buildernet.org/blog/introducing-buildernet
  • https://buildernet.org/docs
  • https://buildernet.org/docs/architecture
  • https://buildernet.org/docs/flashbots-infra
  • https://buildernet.org/docs/send-orderflow
  • https://buildernet.org/docs/encryption-attestations
  • https://buildernet.org/docs/api
  • https://github.com/flashbots/builder-hub
  • https://raw.githubusercontent.com/flashbots/builder-hub/main/README.md

Internal linkages

• Keep this note on the strongest structural comparisons: flashbots-auction, mev-boost, and jito.

• Useful cut: BuilderNet is the shared-builder branch of the stack, not a hub that needs to fan out into every adjacent execution-rights market.

• Last reviewed: 2026-06-01 UTC