# AntiSnipeRamp

> Opens a pool at a punitive fee that decays to normal over a fixed window, and pays every cent of the difference to liquidity providers rather than to the deployer.

A production Uniswap v4 hook. Source: https://github.com/nirholas/anti-snipe-ramp. Part of the HookForge catalogue: https://hookforge.pages.dev

## How it works
The first block of a new pool is the most valuable block it will ever have. A bot that buys in it and sells an hour later takes the entire launch premium, and everyone who arrives through the front door pays for it. The usual answers are a whitelist, which is a promise rather than a mechanism, or a bonding curve that hands the premium to the deployer, which moves the extraction rather than removing it. This hook makes the first block expensive to trade in and lets that expense decay:   fee(t) = startFee - (startFee - endFee) * min(t, rampSeconds) / rampSeconds A sniper in the first second pays `startFee`, which can be set high enough that the trade is not worth making. A buyer twenty minutes later pays close to `endFee`. Because the fee is an LP fee, the premium the early trader surrenders is paid to the people who put the liquidity up, not to whoever deployed the token. There is no address in this contract that can receive anything. A second lever handles the case where the fee alone is not enough. While the ramp is running, a single swap may not exceed `maxSwapDuringRamp` units of the specified currency. This is a size cap, not an identity check, and it is deliberately not per-address: a hook sees the router that called the `PoolManager`, not the person behind it, so any per-address limit is a limit on routers and is defeated by a fresh key. Capping size is enforceable against everyone equally, including the deployer. Set it to zero to disable it. Prior art: liquidity bootstrapping pools ramp the *price* down and were built for price discovery; several launchpad hooks charge a launch fee and route it to a creator or a protocol treasury. Ramping the *fee* down while directing the proceeds to liquidity is a different mechanism with a different beneficiary, and it composes with any curve rather than replacing it.

## Prior art
Liquidity bootstrapping pools ramp the price down and were built for price discovery; several launchpad hooks charge a launch fee and route it to a creator or a treasury. Ramping the fee down while directing the proceeds to liquidity is a different mechanism with a different beneficiary, and it composes with any curve rather than replacing it.

## Where it does not help
The size cap is per swap, not per address: a hook sees the router that called the PoolManager, not the person behind it, so a determined buyer can split across transactions. The cap raises the cost of sniping rather than preventing it, and the fee ramp is what does the real work.

## Facts
Slug: anti-snipe-ramp
Contract: AntiSnipeRampHook
Callbacks: beforeSwap, afterInitialize
Parameters: startFee (uint24), endFee (uint24), rampSeconds (uint32), maxSwapDuringRamp (uint128)
Dynamic fee required: yes

## Caveats
- Unaudited.
- A deployment with status "deterministic" is a mined CREATE2 address with no code at it yet. Never present one as live.