UruLaunchHook on Robinhood Chain

Volume (24h)

$108

Value locked (TVL)

$13.92K

All-time volume

$1.69M

Pools using this hook

1

Swaps (24h)

8 (8 traders)

Total swaps

7,903

What it does

A Uniswap v4 hook for the URU/WETH launch pool that meters URU swap volume per epoch and charges a sniper tax on swaps during the launch window, decaying from 99% to 1% and then to zero, with the tax sent to a vault.

How it works step by step

• Validates that swaps come from the URU/WETH pool with this hook, fee 0.30% and tick spacing 60
• Aggregates URU volume per epoch and emits SwapMetered events
• Computes a bounded emission-rate signal between 66.67% and 200% of base from epoch volume versus target
• Collects a linearly decaying sniper tax from 99% to 1% over the launch duration and then 0
• Sends collected tax to the configured vault via poolManager.take and reports it through the return delta

Swap behaviour

On each swap, afterSwap validates the pool key, rolls the epoch, adds URU volume above the minimum to the current epoch total and emits a rate signal. During the sniper window it takes a tax on the unspecified currency and sends it to the vault, returning the amount through the return delta.

Liquidity behaviour

No liquidity callbacks.

Fee behaviour

Takes a decaying sniper tax on swaps during the launch window: starts at 99% of the unspecified-side amount at launch and decays linearly to 1% over sniperDurationSeconds, then drops to 0. The tax is taken via the afterSwap return delta and sent to the vault. The pool itself uses a static 0.30% fee tier (EXPECTED_FEE = 3000) with tick spacing 60.

Owner & admin controls

Owner (Ownable2Step) can set the vault address that receives sniper tax, and change epochSeconds, targetEpochVolume and minUruVolume via setVolumeConfig, which also rolls the epoch. Ownership transfer is two-step with acceptOwnership; renounceOwnership is available. The sniper tax schedule is fixed by immutable constants and launch timestamp and cannot be changed by the owner.

Enabled Uniswap v4 callbacks

afterSwap, afterSwapReturnDelta

afterSwap: meters URU volume per epoch to compute an emission-rate signal and applies the sniper tax. afterSwapReturnDelta: lets the hook claim part of the swap output as a custom-accounting delta, which is how the tax is collected.

Security & trust assessment

Risk level: medium (verified source, high confidence).

Who controls it: The owner cannot alter the sniper tax curve or the pool-key checks, but can redirect all future sniper tax to any address via setVault and reconfigure the volume metering parameters that feed the emission-rate signal. Ownership can also be renounced or transferred to a new key.

Risk to user funds: The hook can take a share of swap output as tax during the launch window and send it to the vault; it does not hold user balances between transactions, but it can take up to the full unspecified-side amount, which at the start of the window is up to 99% of that leg. Changing the vault redirects future taxes.

Security findings

• [medium] Owner-controlled tax destination: Sniper tax is taken on every swap in the launch window and sent to the vault, so early buyers and sellers pay up to 99% of the unspecified leg; the owner can point the vault to any address.
• [info] Hook moves pool currency: Tax amount is derived from the unspecified-currency delta and taken through poolManager.take, so the hook holds rights to move pool funds on each qualifying swap.
• [info] Pool key restriction: Swaps are only accepted for pools whose key uses this hook, the URU/WETH pair, fee 3000 and tick spacing 60; other pools revert.
• [low] Rate signal depends on owner parameters: The emission-rate signal (currentRateBps) is computed from on-chain volume and is exposed to external consumers via IUruEmissionRateProvider; the owner can change its target and minimum parameters, which affects the output.

Contract details

Verified source

Yes (UruLaunchHook)

Compiler

solc 0.8.26+commit.8a97fa7a

Bytecode size

4,401 bytes

Upgradeable proxy

No

Detected patterns

launchpad, liquidity-management, mev-protection, moves-currency, ownable, return-delta, tax

Pools using UruLaunchHook

• WETH / URU (0.30% fee) — 24h volume $108, TVL $13.92K, 8 swaps today