feat(types,mev): SERVO mempool source, EIP-7702 authorizations, SERVO bid sender - #219
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…e SERVO bid sender SERVO 2.0 is Consensys/MetaMask's order-flow auction: it streams signed pending txs and bundles over a websocket and takes backrun bids back as eth_sendBundle, where the bid IS the backrun's priority fee (no coinbase transfer, no stake, and settlement is conditional on the bundle landing). types: - MempoolSource gets Servo. Appended, never inserted: the values are persisted in pending-pool IDs, trade rows and bot configs. - Message.GetAllLogs must list Servo explicitly — its default arm returns NO logs, which downstream reads as "not a swap" and silently drops the victim. - Message.AuthorizationList carries an EIP-7702 (type 0x4) victim's authorizations. They install code on the signing EOA before execution, so a re-simulation without them runs against a bare EOA and returns success with no logs rather than an error. SERVO is MetaMask flow, where smart-account delegation txs are expected, and its tx frames carry authorizationList. - CallFrame.AuthorizationList carries the same per FRAME, which is what a merged pending BUNDLE needs: it flattens its members into Calls, so a bundle-level list cannot say which member an authorization belongs to. Applying one member's delegation before an earlier member runs changes what that earlier call sees, and can flip the authorization's own nonce check. mev: - ServoSender implements IBackrunSender against SERVO's HTTP endpoint with X-Api-Key auth. Its params object is its own type rather than SendBundleParams, which emits `ReplacementUuid` (capital R) and an unsolicited allowBuilderNetRefunds — neither of which SERVO documents. - SERVO's blockNumber is a DEADLINE, not a target: the bid is retried every block up to it, and omitting it means 5 blocks of retries on statically-priced calldata. The sender therefore folds blockNumber/maxBlockNumber into that deadline and refuses to send a bid without one. - targetBuilders and coinbaseProfit are ignored: SERVO chooses the builders. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01Bof9gJLKZ8oWxLB4uw354P
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Adds everything the SERVO 2.0 order-flow auction needs at the library level, so
mempool-explorer, dexdex-arb, reserve-taker and poseidon can depend on one tag.
This must be tagged before the four downstream PRs are mergeable — they
currently carry a
replace github.com/KyberNetwork/tradinglib => ../tradinglibline with a
TODO(servo)comment, to be swapped for arequirebump.types
MempoolSourcegetsServo(10). Appended, never inserted: the values arepersisted in pending-pool IDs, trade rows and bot configs.
Message.GetAllLogslistsServoexplicitly. Itsdefaultarm returns nologs, which downstream reads as "not a swap" — a missing arm silently drops
every victim of the new source.
Message.AuthorizationListcarries an EIP-7702 (type0x4) victim'sauthorizations. They install code on the signing EOA before execution, so a
re-simulation without them runs against a bare EOA and returns success with
no logs rather than an error. SERVO is MetaMask flow, where smart-account
delegation txs are expected, and its tx frames carry
authorizationList.mev
ServoSenderimplementsIBackrunSenderagainst SERVO's HTTP endpoint withX-Api-Keyauth (SERVO signs nothing).SendBundleParams, which emitsReplacementUuid(capital R) and an unsolicitedallowBuilderNetRefunds—neither of which SERVO documents.
blockNumberis a deadline, not a target: the bid is retried everyblock up to it, and omitting it means 5 blocks of retries on statically-priced
calldata. The sender folds
blockNumber/maxBlockNumberinto that deadlineand refuses to send a bid without one.
targetBuildersandcoinbaseProfitare ignored — SERVO picks the builders.Tests cover the exact wire shape (hash order, deadline,
replacementUuid, theAPI-key header) and every incomplete-bid rejection.
🤖 Generated with Claude Code
https://claude.ai/code/session_01Bof9gJLKZ8oWxLB4uw354P