Release Stoploss (token symbol STOP) on Sepolia as a univ4_hook launch.

Token: Stoploss (STOP), total supply 1,000,000,000 STOP with 18 decimals, minted once to the deployer.

Hook: StopLossHook, a Uniswap v4 hook on the token's native-ETH pool (currency0 native ETH, currency1 STOP, LP fee 3000, tickSpacing 60; the factory seeds one-sided STOP liquidity, so the first buy lands in a pool holding no ETH). In v4, amountSpecified < 0 is exact input and zeroForOne is a buy (ETH in, STOP out).

Orientation: tick = log base 1.0001 of STOP per ETH, so STOP's ETH price FALLS as the tick RISES; sells (oneForZero) push the tick up and are what trigger a stop-loss. The hook extends v4-periphery BaseHook; constructor (IPoolManager poolManager) with the Sepolia PoolManager 0xE03A1074c86CFeDd5C142C4F04F1a1536e203543. getHookPermissions enables exactly beforeSwap and afterSwap (no return deltas); the manifest lists the same set.

State is keyed by PoolId, so any pool may attach the hook. No owner, no admin, no fee.

Orders: placeOrder(PoolKey key, int24 triggerTick, uint128 amount) pulls amount STOP from the caller (approve first), requires amount >= 1 STOP, triggerTick a multiple of 60 and strictly above the current tick, and returns an orderId. Orders at one triggerTick share a bucket; each bucket has an open epoch, and an order joins the open epoch. cancel(orderId): owner only, only while its epoch is unexecuted; refunds the STOP.

Execution: beforeSwap stores the pre-swap tick in transient storage. afterSwap, for sells only, finds buckets with triggerTick in (tickBefore, tickAfter] using a bitmap of active trigger ticks (reuse v4-core's TickBitmap library, scanning at most 4 words) and executes up to 5 of those buckets, lowest trigger first; levels crossed only by the hook's own sells are left for execute().

A bucket is executed only while the current tick is below its triggerTick + 1200: a limit on the wrong side of the price would make the PoolManager revert the user's sell, so a bucket the price has already jumped past is skipped, stays open and cancellable, and execute() fills it if the price comes back inside that window.

Each bucket's epoch is sold in one internal poolManager.swap (hook as caller, so the PoolManager does not re-enter the hook), exact input, sqrtPriceLimit at triggerTick + 1200 (STOP about 11% cheaper in ETH than at the trigger price) so a thin pool cannot dump an order to nothing. The hook settles the STOP it sells (sync, transfer, settle) and mints the ETH output as ERC-6909 claims; its deltas are zero before afterSwap returns.

STOP left unsold at the limit stays with that epoch.

The epoch is closed either way; later orders at that tick open a new epoch. execute(PoolKey key, uint256 maxBuckets <= 5) is permissionless: it unlocks the PoolManager and executes open buckets whose trigger is at or below the current tick (catch-up after a crossing of more than 5 levels or by the hook's own sells; it skips buckets whose limit the price has passed, as above). claim(orderId): owner only, once, after execution: pays ETH = epochEthOut x amount / epochAmount (burning claims and taking native ETH to the owner) and unsold STOP = epochUnsold x amount / epochAmount, both rounded down; rounding dust stays in the hook and is documented. unlockCallback accepts only the PoolManager during a call the hook started; placeOrder, cancel, claim and execute are nonReentrant.

Events: OrderPlaced(orderId, owner, poolId, triggerTick, amount, epoch), OrderCancelled(orderId), BucketExecuted(poolId, triggerTick, epoch, stopSold, ethOut, unsold), Claimed(orderId, owner, eth, stop).

Views: order(orderId), epoch(poolId, triggerTick, epoch), and the open amount per trigger tick; owner is indexed in OrderPlaced so the site can list a wallet's orders. Tests run against a real v4-core PoolManager and include a launch rehearsal: one-sided STOP liquidity below the opening price, a first buy into the ETH-less pool, then a sell.

Acceptance: invariants: STOP held == open orders + unclaimed unsold; ETH claims held == unclaimed epoch ETH. A sell crossing 7 levels executes 5 and execute() finishes the rest; a sell that jumps more than 1,200 ticks past a trigger succeeds and leaves that bucket open; buys never trigger; the price limit leaves unsold STOP claimable; cancel after execution and a second claim revert; gas of a sell that executes 5 buckets is reported (the seller pays it; say so in the README).

One contract, about 400 lines at most. Then a small website to place (approve, then place), list, cancel and claim orders, show open STOP per trigger price from events, and a swap form. Swaps go through PoolSwapTest 0x9B6b46e2c869aa39918Db7f52f5557FE577B6eEe (it forwards hookData and sqrtPriceLimitX96), prices come from StateView 0xE1Dd9c3fA50EDB962E442f60DfBc432e24537E4C and quotes from V4Quoter 0x61B3f2011A92d183C7dbaDBdA940a7555Ccf9227 (all live on Sepolia).

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