TradingCalendar

How it works

Some assets should not be quoted around the clock at the same spread. A pool whose reference market is open for part of the day is being priced blind the rest of the time, and the liquidity sitting in it overnight is providing a free option to anyone with better information about where the asset will open. The obvious hook for this reverts outside session hours, and several published ones do exactly that.

Reverting is the wrong instrument. A pool that reverts is a pool that every router, aggregator and quoting service must special case; it fails after the user has signed; it strands liquidity providers who wanted to exit; and it converts a pricing problem into a liveness problem. Worse, it does not stop informed flow at all, it just moves it to the first second after the open, where it hits the same liquidity at the same stale price.

This hook keeps the pool open and quotable at every instant and expresses the session in the fee instead: - Inside the session, swaps pay `sessionFee`. - Outside it, swaps pay `closedFee`, which is meant to be punitive rather than prohibitive. - Across `rampSeconds` on either side of each boundary the fee moves linearly between the two, so the open and the close are gradients rather than cliffs and there is no single block worth racing to.

The ramp is the part that matters. A cliff at the open creates a race: the first swap after the boundary captures the whole overnight gap at the session spread. A ramp means the trader who wants that gap must choose between paying for it early and waiting for a lower fee while the price moves against them, which is precisely the tradeoff that makes the gap get closed gradually and by more than one participant.

Sessions are expressed in UTC seconds-of-day and may wrap midnight (`open > close` describes an overnight session). `daysMask` selects the days of the week the session runs, bit 0 being Monday. A pool with `daysMask` covering all seven days and a 24-hour session is always in session, which is a valid way to disable the calendar.

Prior art: "New York Trading Hours" and "Trading Hours" hooks revert outside a window. Continuous fee ramps around scheduled events appear in the `UniCast` design for known catalysts. Expressing a *recurring weekly calendar* as a continuous fee surface, with no revert path and no oracle, is the contribution here.

Using it

Uniswap v4 removed hookData from initialize, so per-pool parameters arrive out of band. Fix them for a pool key whose pool does not exist yet, then initialize. Nobody can change them afterwards, including you.

hook.configure(
    key,
    TradingCalendarHook.Config({
        openSecond: /* uint32 */ 0,
        closeSecond: /* uint32 */ 0,
        rampSeconds: /* uint32 */ 0,
        sessionFee: /* uint24 */ 0,
        closedFee: /* uint24 */ 0,
        daysMask: /* uint8 */ 0
    })
);

poolManager.initialize(key, startingSqrtPriceX96);

The pool's fee field must be LPFeeLibrary.DYNAMIC_FEE_FLAG. The hook rejects a pool initialized without it, which is the most common integration failure.

Parameters

From TypeScript

npm i @hookforge/sdk

import {getHook, hookAddress, poolKeyFor} from "@hookforge/sdk";

const hook = getHook("trading-calendar");
const key  = poolKeyFor({
  hook: hookAddress("trading-calendar", 8453),   // Base
  currencyA: USDC, currencyB: WETH,
  tickSpacing: 60, dynamicFee: true,
});

What it reverts with

The callbacks it claims

Uniswap v4 reads a hook's permissions from the low fourteen bits of its own address, which is why deploying one means mining a CREATE2 salt. This hook claims 2, so every deployment of it has an address ending in 0x1080.

• beforeInitialize
• afterInitialize
• beforeAddLiquidity
• afterAddLiquidity
• beforeRemoveLiquidity
• afterRemoveLiquidity
• beforeSwap
• afterSwap
• beforeDonate
• afterDonate
• beforeSwapReturnsDelta
• afterSwapReturnsDelta
• afterAddLiquidityReturnsDelta
• afterRemoveLiquidityReturnsDelta

It says what it is, on-chain

Nothing about a hook's address tells an indexer, a wallet, a router or an agent what the pool does, which is why hook discovery today is a curated list. This hook answers for itself, in one eth_call, with no registry in the loop.

cast call $HOOK "hookName()(string)"    # TradingCalendar
cast call $HOOK "specURI()(string)"     # https://trading-calendar-6bp.pages.dev/hook.json
cast call $HOOK "hookTags()(string[])"  # dynamic-fee, schedule, rwa, oracle-free

Build, test and deploy

git clone --recurse-submodules https://github.com/nirholas/trading-calendar
cd trading-calendar
forge build && forge test

# Dry run: mines the salt, prints the address, sends nothing.
forge script script/Deploy.s.sol --rpc-url $RPC_URL

# For real.
forge script script/Deploy.s.sol --rpc-url $RPC_URL --broadcast --verify