Approved workflow

Release Band (token symbol BAND) on Sepolia as a univ4_hook launch. Token: Band (BAND), total supply 1,000,000,000 BAND with 18 decimals, minted once to the deployer. Hook: PriceBandHook, a Uniswap v4 hook on the token's native-ETH pool (currency0 native ETH, currency1 BAND, LP fee 3000, tickSpacing 60; the factory seeds one-sided BAND 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, BAND out). The hook extends v4-periphery BaseHook; constructor (IPoolManager poolManager) with the Sepolia PoolManager 0xE03A1074c86CFeDd5C142C4F04F1a1536e203543. getHookPermissions enables exactly afterInitialize and afterSwap (no deltas, no fees); the manifest lists the same set. State is keyed by PoolId, so any pool may attach the hook. No owner, no admin. Prices are pool ticks (tick = log base 1.0001 of BAND per ETH). Hours are UTC: h = block.timestamp / 3600. afterInitialize records the tick and time. On every swap, afterSwap first rolls a time-weighted accumulator forward from the last update to block.timestamp at lastTick (the tick after the previous swap; only swaps move it), closing each hour boundary it crosses: a closed hour's average = sum(tick x seconds) / seconds covered, rounded toward negative infinity; the initialisation hour covers only the seconds after initialisation; an hour with no swap averages to the tick that held throughout, so a gap of any length costs O(1) gas. Band: from the last completed hour's average A, lower = A - 2231 and upper = A + 1823 ticks inclusive (1.0001^-2231 ~ 0.80 and 1.0001^1823 ~ 1.20, i.e. BAND per ETH within 80%-120% of the average; BAND's ETH price within about 83%-125%). Until the first hour completes there is no band. With t0 = lastTick and t1 = the tick after the swap, the swap is allowed if lower <= t1 <= upper, or if t1 is strictly closer to the band than t0 (a swap back toward the band is never blocked, so the pool cannot freeze); otherwise afterSwap reverts PriceOutOfBand(t1, lower, upper). Then lastTick = t1. Events: HourClosed(PoolId indexed poolId, uint256 hour, int24 avgTick) for the latest hour a swap closes. Views: band(PoolId) -> (bool active, int24 avgTick, int24 lower, int24 upper, uint256 hour) computed as of block.timestamp exactly as the next swap would, and lastTick(PoolId). Tests run against a real v4-core PoolManager and include a launch rehearsal: one-sided BAND liquidity below the opening price, a first buy into the ETH-less pool, then a sell. Acceptance (vm.warp): first hour unbounded; edges inclusive and one tick outside reverts; a swap moving toward the band from outside is allowed; a 1-hour and a 1,000-hour gap give the right average; negative ticks round down; band() equals what the next swap enforces. Then a small website that shows the last completed hour's average price (in ETH per BAND and BAND per ETH), the allowed band, the current price and whether the band is active, and a swap form that sets sqrtPriceLimitX96 one tick inside the band edge (a swap that stops exactly on an initialized edge tick while falling reports the tick below it) so an oversized swap fills partially instead of reverting. Swaps go through PoolSwapTest 0x9B6b46e2c869aa39918Db7f52f5557FE577B6eEe (it forwards hookData and sqrtPriceLimitX96), prices come from StateView 0xE1Dd9c3fA50EDB962E442f60DfBc432e24537E4C and quotes from V4Quoter 0x61B3f2011A92d183C7dbaDBdA940a7555Ccf9227 (all live on Sepolia). One page, no backend.

Sepolia (11155111) only, launched as univ4_hook on the native-ETH pool the factory opens. GitHub publication and IPFS hosting are approved. Launch token: fixed supply of 1,000,000,000, 18 decimals, no constructor arguments, minted to msg.sender, no mint or admin. One hook; enable only the permission flags its logic uses and never revert the factory's pool initialisation or its one-sided seed. Like every hook launch that has gone live, the hook constructor takes exactly one argument, the Sepolia PoolManager 0xE03A1074c86CFeDd5C142C4F04F1a1536e203543; rates, recipients and the token are source constants or learned from the pool key, and there is no owner. Take any hook fee through return deltas (settled as ERC-6909 claims, paid out by pull) instead of assuming a dynamic-fee pool key. Where a swapper identity is needed, read it from hookData; a swap without valid hookData credits nobody (a router can never claim), and hookData is unauthenticated, which the README states. No external oracles or VRF, no proxies, delegatecall or selfdestruct. foundry.toml sets bytecode_hash = "none". Any website is a static export with index.html in dist/. Site label lab-price-band-hook.

Build BAND and PriceBandHook exactly as the request specifies, with the named tests and an independent review, deploy them through the factory, then build the one-page website against the live pool.

One page: last hour's average, band edges, current price, band-aware swap form via PoolSwapTest. No backend.