0) TL;DR
Prop AMMs can only deliver tight spreads and safe, frequent re-quotes if makers can rely on a predictable and verifiable execution priority for their quote/update/cancel transactions. Today, unpredictable ordering turns the public mempool into a toxic-flow machine: makers are systematically picked off, MEV (sandwich/backrun) rises, and spreads widen.
1) Background & Problem Statement
1.1 What “toxic flow” means for prop AMMs
Prop AMMs continuously adjust quotes based on market signals. In an environment where transaction ordering is manipulable:
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Searchers can wait for quote updates then insert a trade immediately before/after (backrun/sandwich).
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Makers face systematic adverse selection: profitable trades flow in only when makers are stale; neutral flow is crowded out.
1.2 Why prop AMM needs ordering determinism
Prop AMMs rely on rapid quote/update/cancel loops. If transaction ordering is unpredictable, they are exposed to:
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Adverse selection (being picked off when price moves)
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Sandwich/backrun around AMM updates
1.3 Why current EVM flow is insufficient
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Public mempool + builder execution allows reordering and priority games
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Even faster quote updates don’t help if others can insert/reorder within the same block
2) Goals
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Provide verifiable, predictable ordering guarantees for prop AMM flows
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Reduce sandwich/backrun and improve maker viability (tighter spreads, deeper liquidity)
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Minimize protocol changes; enable incremental rollout
3) What we’re looking for
We invite teams to propose implementable designs for ordering determinism that reduce toxic flow for prop AMMs. Please include the ordering rule, verification method, enforcement/penalty mechanism, expected MEV reduction and a phased rollout plan.
Potentials Mechanism type:
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Preconfirmations / ordering commitments
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Protected lane (prop-AMM critical tx types)
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Deterministic in-block ordering rule
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Hybrid approach