Why the 'Alt Mempool' is a Misnomer for a Proprietary Queue

Alt Mempool is a misnomer. The term implies a parallel, permissionless system like Ethereum's public mempool. In reality, it describes a private, centralized queue operated by a single entity like Flashbots' SUAVE or Jito Labs. This is a proprietary order flow auction, not an alternative public resource.

The core innovation is bundling. These systems aggregate user intents off-chain and execute them in a single, profitable bundle. This creates a centralized point of failure and rent extraction that contradicts the decentralized ethos of public mempools. The value accrues to the sequencer, not the network.

Evidence from MEV-Boost. Flashbots' dominance in Ethereum block building, controlling over 90% of MEV-Boost blocks, demonstrates how a single 'alt mempool' operator can capture and centralize the most valuable transaction flow. This is the model being replicated.

Proprietary Queue Architecture: The system is a centralized sequencer's private queue. It does not broadcast transactions for open competition. This design is a permissioned intake mechanism for a single operator, not a shared public resource.

Contrast with Public Mempools: A true mempool like Ethereum's is a public broadcast layer. Transactions are visible to all builders and searchers, enabling open market competition for inclusion. The 'Alt Mempool' eliminates this market.

Intent-Based Parallel: This mirrors the shift from AMMs to intent-based systems like UniswapX and CowSwap. It replaces open execution with a black-box resolver network, centralizing routing logic and value capture.

Evidence: The architecture requires explicit integration. Users cannot submit a generic transaction; they must use the system's specific SDK, creating a walled garden for order flow similar to private RPC endpoints.

The 'Alt Mempool' is a misnomer. It is not a public, permissionless pool. It is a proprietary transaction queue controlled by a single entity, the bundler, which selects and orders transactions before submission to the base chain.

This creates a bundler monopoly. The entity controlling this queue dictates transaction inclusion and ordering, replicating the centralization problems of traditional block builders like Flashbots on Ethereum. This is the new MEV bottleneck.

The bundler extracts new MEV. By seeing all user intents first, the bundler can perform cross-domain MEV extraction, arbitraging between rollup states and L1, a privilege not available to public mempool searchers.

Evidence: In intent-based systems like UniswapX or Across, the solver/bridger fulfilling the order holds this monopolistic position. The economic model shifts from public auction to private capture.

Permissionless execution is irrelevant when the value is in order flow. Anyone can run a bundler client, but the order flow auction is the real asset. This is the proprietary queue.

The mempool is the marketplace. A public mempool like Ethereum's is a common resource. An intent-based alt mempool is a private order book controlled by the auctioneer, like UniswapX or CowSwap.

Economic logic is the moat. The solver competition and MEV capture algorithms are the core IP. This logic is not a forkable protocol; it's a centralized service layer.

Evidence: Flashbots SUAVE aims to be this public mempool, proving the current model is private. Without a standard like SUAVE, intent architectures create walled gardens, not open networks.

Suave is a private queue. It centralizes transaction flow into a single, permissioned sequencer operated by Flashbots. This architecture contradicts the 'mempool' label, which implies a public, decentralized broadcast layer.

The goal is MEV capture. By routing user intents through its centralized relay, Suave internalizes the value extraction process. This contrasts with public mempools like Ethereum's, where searchers and builders compete in an open market.

It competes with existing solvers. Protocols like CowSwap and UniswapX already operate private orderflow auctions (OFAs). Suave attempts to become the universal OFA, but faces adoption hurdles against established, application-specific networks.

Evidence: Centralized point of failure. The current testnet implementation has a single sequencer. This creates a critical vulnerability and regulatory target, unlike the distributed nature of Ethereum's peer-to-peer gossip protocol.