diff --git a/.forge-snapshots/autodynamic fee.snap b/.forge-snapshots/autodynamic fee.snap
new file mode 100644
index 00000000..58d87c97
--- /dev/null
+++ b/.forge-snapshots/autodynamic fee.snap
@@ -0,0 +1 @@
+242952
\ No newline at end of file
diff --git a/.forge-snapshots/counter.snap b/.forge-snapshots/counter.snap
index 7573abf5..4a86f960 100644
--- a/.forge-snapshots/counter.snap
+++ b/.forge-snapshots/counter.snap
@@ -1 +1 @@
-339161
\ No newline at end of file
+358444
\ No newline at end of file
diff --git a/.forge-snapshots/hookFee.snap b/.forge-snapshots/hookFee.snap
index c0ced99f..16c3b790 100644
--- a/.forge-snapshots/hookFee.snap
+++ b/.forge-snapshots/hookFee.snap
@@ -1 +1 @@
-246486
\ No newline at end of file
+265804
\ No newline at end of file
diff --git a/.forge-snapshots/manual dynamic fee.snap b/.forge-snapshots/manual dynamic fee.snap
new file mode 100644
index 00000000..8b180eb5
--- /dev/null
+++ b/.forge-snapshots/manual dynamic fee.snap
@@ -0,0 +1 @@
+219217
\ No newline at end of file
diff --git a/README.md b/README.md
index 737e983c..16f36880 100644
--- a/README.md
+++ b/README.md
@@ -54,3 +54,5 @@ Generate react, register routes, and rebuild search index
```bash
npm run generate
```
+
+Update the [changelog](src/pages/index.tsx#L11)
\ No newline at end of file
diff --git a/forge-test/Counter.t.sol b/forge-test/Counter.t.sol
index 03f54023..69f7cf51 100644
--- a/forge-test/Counter.t.sol
+++ b/forge-test/Counter.t.sol
@@ -30,8 +30,10 @@ contract CounterTest is HookTest, GasSnapshot {
HookTest.initHookTestEnv();
// Deploy the hook to an address with the correct flags
- uint160 flags =
- uint160(Hooks.BEFORE_SWAP_FLAG | Hooks.AFTER_SWAP_FLAG | Hooks.BEFORE_ADD_LIQUIDITY_FLAG | Hooks.BEFORE_REMOVE_LIQUIDITY_FLAG);
+ uint160 flags = uint160(
+ Hooks.BEFORE_SWAP_FLAG | Hooks.AFTER_SWAP_FLAG | Hooks.BEFORE_ADD_LIQUIDITY_FLAG
+ | Hooks.BEFORE_REMOVE_LIQUIDITY_FLAG
+ );
(address hookAddress, bytes32 salt) =
HookMiner.find(address(this), flags, type(Counter).creationCode, abi.encode(address(manager)));
counter = new Counter{salt: salt}(IPoolManager(address(manager)));
diff --git a/forge-test/DynamicFees.t.sol b/forge-test/DynamicFees.t.sol
new file mode 100644
index 00000000..37b85bcf
--- /dev/null
+++ b/forge-test/DynamicFees.t.sol
@@ -0,0 +1,207 @@
+// SPDX-License-Identifier: MIT
+pragma solidity ^0.8.19;
+
+import "forge-std/Test.sol";
+import {IHooks} from "v4-core/interfaces/IHooks.sol";
+import {Hooks} from "v4-core/libraries/Hooks.sol";
+import {TickMath} from "v4-core/libraries/TickMath.sol";
+import {IPoolManager} from "v4-core/interfaces/IPoolManager.sol";
+import {PoolKey} from "v4-core/types/PoolKey.sol";
+import {BalanceDelta} from "v4-core/types/BalanceDelta.sol";
+import {PoolId, PoolIdLibrary} from "v4-core/types/PoolId.sol";
+import {Constants} from "v4-core/../test/utils/Constants.sol";
+import {CurrencyLibrary, Currency} from "v4-core/types/Currency.sol";
+import {FeeLibrary} from "v4-core/libraries/FeeLibrary.sol";
+import {HookTest} from "@v4-by-example/utils/HookTest.sol";
+import {HookMiner} from "./utils/HookMiner.sol";
+import {GasSnapshot} from "forge-gas-snapshot/GasSnapshot.sol";
+import {PoolSwapTest} from "v4-core/test/PoolSwapTest.sol";
+import {FixedPointMathLib} from "solmate/utils/FixedPointMathLib.sol";
+
+import {ManualDynamicFee} from "@v4-by-example/pages/fees/dynamic-fee/ManualDynamicFee.sol";
+import {AutoDynamicFee} from "@v4-by-example/pages/fees/dynamic-fee/AutoDynamicFee.sol";
+
+contract DynamicFeesTest is HookTest, GasSnapshot {
+ using FixedPointMathLib for uint256;
+ using PoolIdLibrary for PoolKey;
+ using CurrencyLibrary for Currency;
+
+ AutoDynamicFee autoDynamicFee;
+ ManualDynamicFee manualDynamicFee;
+
+ PoolKey autoDynamicFeePoolKey;
+ PoolKey manualDynamicFeePoolKey;
+
+ function setUp() public {
+ // creates the pool manager, test tokens, and other utility routers
+ HookTest.initHookTestEnv();
+
+ // Deploy the hook to an address with the correct flags
+ uint160 flags = uint160(Hooks.BEFORE_SWAP_FLAG);
+ (address hookAddress, bytes32 salt) =
+ HookMiner.find(address(this), flags, type(AutoDynamicFee).creationCode, abi.encode(address(manager)));
+ autoDynamicFee = new AutoDynamicFee{salt: salt}(IPoolManager(address(manager)));
+ require(address(autoDynamicFee) == hookAddress, "hook address mismatch");
+
+ (hookAddress, salt) =
+ HookMiner.find(address(this), uint160(0), type(ManualDynamicFee).creationCode, abi.encode(address(manager)));
+ manualDynamicFee = new ManualDynamicFee{salt: salt}(IPoolManager(address(manager)));
+ require(address(manualDynamicFee) == hookAddress, "hook address mismatch");
+
+ // Create the pools
+ autoDynamicFeePoolKey = PoolKey(
+ Currency.wrap(address(token0)),
+ Currency.wrap(address(token1)),
+ FeeLibrary.DYNAMIC_FEE_FLAG,
+ 60,
+ IHooks(autoDynamicFee)
+ );
+ initializeRouter.initialize(autoDynamicFeePoolKey, Constants.SQRT_RATIO_1_1, ZERO_BYTES);
+
+ manualDynamicFeePoolKey = PoolKey(
+ Currency.wrap(address(token0)),
+ Currency.wrap(address(token1)),
+ FeeLibrary.DYNAMIC_FEE_FLAG,
+ 60,
+ IHooks(manualDynamicFee)
+ );
+ initializeRouter.initialize(manualDynamicFeePoolKey, Constants.SQRT_RATIO_1_1, ZERO_BYTES);
+
+ // Provide liquidity to the pool
+ modifyPositionRouter.modifyLiquidity(
+ autoDynamicFeePoolKey,
+ IPoolManager.ModifyLiquidityParams(TickMath.minUsableTick(60), TickMath.maxUsableTick(60), 100000 ether),
+ ZERO_BYTES
+ );
+
+ modifyPositionRouter.modifyLiquidity(
+ manualDynamicFeePoolKey,
+ IPoolManager.ModifyLiquidityParams(TickMath.minUsableTick(60), TickMath.maxUsableTick(60), 100000 ether),
+ ZERO_BYTES
+ );
+ }
+
+ function test_start_autoFee() public {
+ // Perform a test swap //
+ int256 amount = 1e18;
+ bool zeroForOne = true;
+ BalanceDelta swapDelta = swap(autoDynamicFeePoolKey, amount, zeroForOne, ZERO_BYTES);
+ // ------------------- //
+
+ // fee on output token, so expect ~0.95e18 output
+ assertLt(uint256(-int256(swapDelta.amount1())), 0.95e18);
+ assertGt(uint256(-int256(swapDelta.amount1())), 0.94e18);
+ assertApproxEqAbs(
+ uint256(-int256(swapDelta.amount1())), uint256(amount), uint256(amount).mulWadDown(0.05001e18)
+ );
+ }
+
+ function test_floor_autoFee() public {
+ // skip 496,000 seconds, fee is now floored at 0.05%
+ skip(496000);
+
+ // Perform a test swap //
+ int256 amount = 1e18;
+ bool zeroForOne = true;
+ BalanceDelta swapDelta = swap(autoDynamicFeePoolKey, amount, zeroForOne, ZERO_BYTES);
+ // ------------------- //
+
+ assertLt(uint256(-int256(swapDelta.amount1())), 0.9995e18);
+ assertGt(uint256(-int256(swapDelta.amount1())), 0.9994e18);
+ assertApproxEqAbs(
+ uint256(-int256(swapDelta.amount1())), uint256(amount), uint256(amount).mulWadDown(0.00051e18)
+ );
+ }
+
+ function test_start_manualFee() public {
+ // Perform a test swap //
+ int256 amount = 1e18;
+ bool zeroForOne = true;
+ BalanceDelta swapDelta = swap(manualDynamicFeePoolKey, amount, zeroForOne, ZERO_BYTES);
+ // ------------------- //
+
+ // fee on output token, so expect ~0.95e18 output
+ assertLt(uint256(-int256(swapDelta.amount1())), 0.95e18);
+ assertGt(uint256(-int256(swapDelta.amount1())), 0.94e18);
+ assertApproxEqAbs(
+ uint256(-int256(swapDelta.amount1())), uint256(amount), uint256(amount).mulWadDown(0.05001e18)
+ );
+ }
+
+ function test_floor_manualFee() public {
+ // skip 496,000 seconds, fee is now floored at 0.05%
+ skip(496000);
+
+ // poke the pool manager
+ manager.updateDynamicSwapFee(manualDynamicFeePoolKey);
+
+ // Perform a test swap //
+ int256 amount = 1e18;
+ bool zeroForOne = true;
+ BalanceDelta swapDelta = swap(manualDynamicFeePoolKey, amount, zeroForOne, ZERO_BYTES);
+ // ------------------- //
+
+ assertLt(uint256(-int256(swapDelta.amount1())), 0.9995e18);
+ assertGt(uint256(-int256(swapDelta.amount1())), 0.9994e18);
+ assertApproxEqAbs(
+ uint256(-int256(swapDelta.amount1())), uint256(amount), uint256(amount).mulWadDown(0.00051e18)
+ );
+ }
+
+ function test_staleFee_manualFee() public {
+ // skip 496,000 seconds, but the fee is still 5% since its stale and wasnt updated
+ skip(496000);
+
+ // Perform a test swap //
+ int256 amount = 1e18;
+ bool zeroForOne = true;
+ BalanceDelta swapDelta = swap(manualDynamicFeePoolKey, amount, zeroForOne, ZERO_BYTES);
+ // ------------------- //
+
+ // fee on output token, so expect ~0.95e18 output
+ assertLt(uint256(-int256(swapDelta.amount1())), 0.95e18);
+ assertGt(uint256(-int256(swapDelta.amount1())), 0.94e18);
+ assertApproxEqAbs(
+ uint256(-int256(swapDelta.amount1())), uint256(amount), uint256(amount).mulWadDown(0.05001e18)
+ );
+ }
+
+ function test_snapshot_autoFee() public {
+ skip(100_000);
+ int256 amount = 1e18;
+ bool zeroForOne = true;
+ IPoolManager.SwapParams memory params = IPoolManager.SwapParams({
+ zeroForOne: zeroForOne,
+ amountSpecified: amount,
+ sqrtPriceLimitX96: zeroForOne ? MIN_PRICE_LIMIT : MAX_PRICE_LIMIT // unlimited impact
+ });
+
+ PoolSwapTest.TestSettings memory testSettings =
+ PoolSwapTest.TestSettings({withdrawTokens: true, settleUsingTransfer: true, currencyAlreadySent: false});
+
+ snapStart("autodynamic fee");
+ swapRouter.swap(autoDynamicFeePoolKey, params, testSettings, ZERO_BYTES);
+ snapEnd();
+ }
+
+ function test_snapshot_manualFee() public {
+ skip(100_000);
+ // poke the pool manager
+ manager.updateDynamicSwapFee(manualDynamicFeePoolKey);
+
+ int256 amount = 1e18;
+ bool zeroForOne = true;
+ IPoolManager.SwapParams memory params = IPoolManager.SwapParams({
+ zeroForOne: zeroForOne,
+ amountSpecified: amount,
+ sqrtPriceLimitX96: zeroForOne ? MIN_PRICE_LIMIT : MAX_PRICE_LIMIT // unlimited impact
+ });
+
+ PoolSwapTest.TestSettings memory testSettings =
+ PoolSwapTest.TestSettings({withdrawTokens: true, settleUsingTransfer: true, currencyAlreadySent: false});
+
+ snapStart("manual dynamic fee");
+ swapRouter.swap(manualDynamicFeePoolKey, params, testSettings, ZERO_BYTES);
+ snapEnd();
+ }
+}
diff --git a/forge-test/utils/HookMiner.sol b/forge-test/utils/HookMiner.sol
index 31bd8144..ca421b5b 100644
--- a/forge-test/utils/HookMiner.sol
+++ b/forge-test/utils/HookMiner.sol
@@ -8,7 +8,7 @@ library HookMiner {
uint160 constant FLAG_MASK = 0xFFF << 148;
// Maximum number of iterations to find a salt, avoid infinite loops
- uint256 constant MAX_LOOP = 10_000;
+ uint256 constant MAX_LOOP = 20_000;
/// @notice Find a salt that produces a hook address with the desired `flags`
/// @param deployer The address that will deploy the hook. In `forge test`, this will be the test contract `address(this)` or the pranking address
diff --git a/src/keywords.json b/src/keywords.json
index 5ebfb955..298e092a 100644
--- a/src/keywords.json
+++ b/src/keywords.json
@@ -45,6 +45,13 @@
"static fee",
"hook fee"
],
+ "/fees/dynamic-fee": [
+ "fee",
+ "fees",
+ "dynamic fee",
+ "dynamic",
+ "poke"
+ ],
"/create-liquidity": [
"liquidity",
"LP",
diff --git a/src/nav.ts b/src/nav.ts
index b995a19b..abb8c262 100644
--- a/src/nav.ts
+++ b/src/nav.ts
@@ -44,6 +44,10 @@ const FEE_ROUTES: Route[] = [
{
path: "fixed-hook-fee",
title: "Static Hook Fee"
+ },
+ {
+ path: "dynamic-fee",
+ title: "Dynamic Swap Fee"
}
]
diff --git a/src/pages/fees/dynamic-fee/AutoDynamicFee.sol b/src/pages/fees/dynamic-fee/AutoDynamicFee.sol
new file mode 100644
index 00000000..334c892f
--- /dev/null
+++ b/src/pages/fees/dynamic-fee/AutoDynamicFee.sol
@@ -0,0 +1,63 @@
+// SPDX-License-Identifier: MIT
+pragma solidity ^0.8.19;
+
+// TODO: update to v4-periphery/BaseHook.sol when its compatible
+import {BaseHook} from "@v4-by-example/utils/BaseHook.sol";
+
+import {Hooks} from "v4-core/libraries/Hooks.sol";
+import {IPoolManager} from "v4-core/interfaces/IPoolManager.sol";
+import {PoolKey} from "v4-core/types/PoolKey.sol";
+import {IDynamicFeeManager} from "v4-core/interfaces/IDynamicFeeManager.sol";
+
+/// @notice A time-decaying dynamically fee, updated automatically with beforeSwap()
+contract AutoDynamicFee is BaseHook, IDynamicFeeManager {
+ uint256 public immutable startTimestamp;
+
+ // Start at 5% fee, decaying at rate of 0.00001% per second
+ // after 495,000 seconds (5.72 days), fee will be a minimum of 0.05%
+ // NOTE: because fees are uint24, we will lose some precision
+ uint128 public constant START_FEE = 500000; // represents 5%
+ uint128 public constant MIN_FEE = 500; // minimum fee of 0.05%
+
+ uint128 public constant decayRate = 1; // 0.00001% per second
+
+ constructor(IPoolManager _poolManager) BaseHook(_poolManager) {
+ startTimestamp = block.timestamp;
+ }
+
+ /// @inheritdoc IDynamicFeeManager
+ function getFee(address, PoolKey calldata) external view override returns (uint24 _currentFee) {
+ unchecked {
+ uint256 timeElapsed = block.timestamp - startTimestamp;
+ _currentFee = timeElapsed > 495000 ? uint24(MIN_FEE) : uint24((START_FEE - (timeElapsed * decayRate)) / 10);
+ }
+ }
+
+ /// @dev this example hook contract does not implement any hooks
+ function getHookPermissions() public pure override returns (Hooks.Permissions memory) {
+ return Hooks.Permissions({
+ beforeInitialize: false,
+ afterInitialize: false,
+ beforeAddLiquidity: false,
+ afterAddLiquidity: false,
+ beforeRemoveLiquidity: false,
+ afterRemoveLiquidity: false,
+ beforeSwap: true,
+ afterSwap: false,
+ beforeDonate: false,
+ afterDonate: false,
+ noOp: false,
+ accessLock: false
+ });
+ }
+
+ function beforeSwap(address, PoolKey calldata key, IPoolManager.SwapParams calldata, bytes calldata)
+ external
+ override
+ returns (bytes4)
+ {
+ // poke the poolmanager to update the fee for every swap
+ poolManager.updateDynamicSwapFee(key);
+ return BaseHook.beforeSwap.selector;
+ }
+}
diff --git a/src/pages/fees/dynamic-fee/ManualDynamicFee.sol b/src/pages/fees/dynamic-fee/ManualDynamicFee.sol
new file mode 100644
index 00000000..01537e32
--- /dev/null
+++ b/src/pages/fees/dynamic-fee/ManualDynamicFee.sol
@@ -0,0 +1,55 @@
+// SPDX-License-Identifier: MIT
+pragma solidity ^0.8.19;
+
+// TODO: update to v4-periphery/BaseHook.sol when its compatible
+import {BaseHook} from "@v4-by-example/utils/BaseHook.sol";
+
+import {Hooks} from "v4-core/libraries/Hooks.sol";
+import {IPoolManager} from "v4-core/interfaces/IPoolManager.sol";
+import {PoolKey} from "v4-core/types/PoolKey.sol";
+import {IDynamicFeeManager} from "v4-core/interfaces/IDynamicFeeManager.sol";
+
+/// @notice A time-decaying dynamically fee, updated manually with external PoolManager.updateDynamicSwapFee() calls
+contract ManualDynamicFee is BaseHook, IDynamicFeeManager {
+ uint256 public immutable startTimestamp;
+
+ // Start at 5% fee, decaying at rate of 0.00001% per second
+ // after 495,000 seconds (5.72 days), fee will be a minimum of 0.05%
+ // NOTE: because fees are uint24, we will lose some precision
+ uint128 public constant START_FEE = 500000; // represents 5%
+ uint128 public constant MIN_FEE = 500; // minimum fee of 0.05%
+
+ uint128 public constant decayRate = 1; // 0.00001% per second
+
+ constructor(IPoolManager _poolManager) BaseHook(_poolManager) {
+ startTimestamp = block.timestamp;
+ }
+
+ /// @dev Deteremines a Pool's swap fee. Called and cached by PoolManager.updateDynamicFee()
+ function getFee(address, PoolKey calldata) external view override returns (uint24 _currentFee) {
+ // Linearly decaying fee, y = mx + b
+ // After 495,000 seconds (5.72 days), fee will be a minimum of 0.05%
+ unchecked {
+ uint256 timeElapsed = block.timestamp - startTimestamp;
+ _currentFee = timeElapsed > 495000 ? uint24(MIN_FEE) : uint24((START_FEE - (timeElapsed * decayRate)) / 10);
+ }
+ }
+
+ /// @dev this example hook contract does not implement any hooks
+ function getHookPermissions() public pure override returns (Hooks.Permissions memory) {
+ return Hooks.Permissions({
+ beforeInitialize: false,
+ afterInitialize: false,
+ beforeAddLiquidity: false,
+ afterAddLiquidity: false,
+ beforeRemoveLiquidity: false,
+ afterRemoveLiquidity: false,
+ beforeSwap: false,
+ afterSwap: false,
+ beforeDonate: false,
+ afterDonate: false,
+ noOp: false,
+ accessLock: false
+ });
+ }
+}
diff --git a/src/pages/fees/dynamic-fee/UpdateDynamicFee.solsnippet b/src/pages/fees/dynamic-fee/UpdateDynamicFee.solsnippet
new file mode 100644
index 00000000..ea580eb3
--- /dev/null
+++ b/src/pages/fees/dynamic-fee/UpdateDynamicFee.solsnippet
@@ -0,0 +1,6 @@
+import {IPoolManager} from "v4-core/interfaces/IPoolManager.sol";
+import {PoolKey} from "v4-core/types/PoolKey.sol";
+
+// poke the poolmanager to update the "dynamic fee"
+PoolKey memory key = PoolKey(...);
+poolManager.updateDynamicSwapFee(key);
diff --git a/src/pages/fees/dynamic-fee/index.html.ts b/src/pages/fees/dynamic-fee/index.html.ts
new file mode 100644
index 00000000..5fbf863d
--- /dev/null
+++ b/src/pages/fees/dynamic-fee/index.html.ts
@@ -0,0 +1,184 @@
+// metadata
+export const version = "0.8.20"
+export const title = "Dynamic Fees"
+export const description = "Design a v4 pool with a dynamic fee"
+
+export const keywords = [
+ "fee",
+ "fees",
+ "dynamic fee",
+ "dynamic",
+ "poke",
+]
+
+export const codes = [
+ {
+ fileName: "AutoDynamicFee.sol",
+ code: "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",
+ },
+ {
+ fileName: "ManualDynamicFee.sol",
+ code: "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",
+ },
+ {
+ fileName: "UpdateDynamicFee.sol",
+ code: "aW1wb3J0IHtJUG9vbE1hbmFnZXJ9IGZyb20gInY0LWNvcmUvaW50ZXJmYWNlcy9JUG9vbE1hbmFnZXIuc29sIjsKaW1wb3J0IHtQb29sS2V5fSBmcm9tICJ2NC1jb3JlL3R5cGVzL1Bvb2xLZXkuc29sIjsKCi8vIHBva2UgdGhlIHBvb2xtYW5hZ2VyIHRvIHVwZGF0ZSB0aGUgImR5bmFtaWMgZmVlIgpQb29sS2V5IG1lbW9yeSBrZXkgPSBQb29sS2V5KC4uLik7CnBvb2xNYW5hZ2VyLnVwZGF0ZUR5bmFtaWNTd2FwRmVlKGtleSk7Cg==",
+ },
+]
+
+const html = `
+- Design a v4 pool with a dynamic fee
+
+Uniswap v4 pools can support dynamic swap fees, and do not need to adhere to a static fee (0.05% / 0.30% / 1.0%). The hook needs to inherit IDynamicFeeManager and use FeeLibrary.DYNAMIC_FEE_FLAG in its PoolKey.fee.
+Despite its name, the fee is cached by the PoolManager and an external call PoolManager.updateDynamicFee() is required to change the swap fee.
+Note: dynamic fees can be computed every swap, but incurs a gas overhead
+
+Initialize a Dynamic Fee Pool
+import {FeeLibrary} from "v4-core/libraries/FeeLibrary.sol";
+
+
+poolKey = PoolKey(
+ Currency.wrap(address(token0)),
+ Currency.wrap(address(token1)),
+ FeeLibrary.DYNAMIC_FEE_FLAG,
+ 60,
+ IHooks(hook)
+);
+initializeRouter.initialize(poolKey, startingPrice, hookData);
+
Example: Manual Dynamic Fee
+Implements a time-decaying dynamic fee
+
+- The swap fee starts at 5.0%
+- The fee decays 0.00001% every second
+- After 495,000 seconds, the minimum fee is set to 0.05%
+
+
+- Inherit
IDynamicFeeManager
+- Implement
getFee()
+- Poke
PoolManager.updateDynamicFee() to change the fee
+
+
+pragma solidity ^0.8.19;
+
+
+import {BaseHook} from "@v4-by-example/utils/BaseHook.sol";
+
+import {Hooks} from "v4-core/libraries/Hooks.sol";
+import {IPoolManager} from "v4-core/interfaces/IPoolManager.sol";
+import {PoolKey} from "v4-core/types/PoolKey.sol";
+import {IDynamicFeeManager} from "v4-core/interfaces/IDynamicFeeManager.sol";
+
+
+contract ManualDynamicFee is BaseHook, IDynamicFeeManager {
+ uint256 public immutable startTimestamp;
+
+
+
+
+ uint128 public constant START_FEE = 500000;
+ uint128 public constant MIN_FEE = 500;
+
+ uint128 public constant decayRate = 1;
+
+ constructor(IPoolManager _poolManager) BaseHook(_poolManager) {
+ startTimestamp = block.timestamp;
+ }
+
+
+ function getFee(address, PoolKey calldata) external view override returns (uint24 _currentFee) {
+
+
+ unchecked {
+ uint256 timeElapsed = block.timestamp - startTimestamp;
+ _currentFee = timeElapsed > 495000 ? uint24(MIN_FEE) : uint24((START_FEE - (timeElapsed * decayRate)) / 10);
+ }
+ }
+
+
+ function getHookPermissions() public pure override returns (Hooks.Permissions memory) {
+ return Hooks.Permissions({
+ beforeInitialize: false,
+ afterInitialize: false,
+ beforeAddLiquidity: false,
+ afterAddLiquidity: false,
+ beforeRemoveLiquidity: false,
+ afterRemoveLiquidity: false,
+ beforeSwap: false,
+ afterSwap: false,
+ beforeDonate: false,
+ afterDonate: false,
+ noOp: false,
+ accessLock: false
+ });
+ }
+}
+
Example: Automatic Dynamic Fee
+Implements an automatically-updated, time-decaying dynamic fee
+The hook uses beforeSwap to automatically poke the PoolManager, ensuring the fee is always up-to-date
+incurs +23,000 gas overhead
+
+pragma solidity ^0.8.19;
+
+
+import {BaseHook} from "@v4-by-example/utils/BaseHook.sol";
+
+import {Hooks} from "v4-core/libraries/Hooks.sol";
+import {IPoolManager} from "v4-core/interfaces/IPoolManager.sol";
+import {PoolKey} from "v4-core/types/PoolKey.sol";
+import {IDynamicFeeManager} from "v4-core/interfaces/IDynamicFeeManager.sol";
+
+
+contract AutoDynamicFee is BaseHook, IDynamicFeeManager {
+ uint256 public immutable startTimestamp;
+
+
+
+
+ uint128 public constant START_FEE = 500000;
+ uint128 public constant MIN_FEE = 500;
+
+ uint128 public constant decayRate = 1;
+
+ constructor(IPoolManager _poolManager) BaseHook(_poolManager) {
+ startTimestamp = block.timestamp;
+ }
+
+
+ function getFee(address, PoolKey calldata) external view override returns (uint24 _currentFee) {
+ unchecked {
+ uint256 timeElapsed = block.timestamp - startTimestamp;
+ _currentFee = timeElapsed > 495000 ? uint24(MIN_FEE) : uint24((START_FEE - (timeElapsed * decayRate)) / 10);
+ }
+ }
+
+
+ function getHookPermissions() public pure override returns (Hooks.Permissions memory) {
+ return Hooks.Permissions({
+ beforeInitialize: false,
+ afterInitialize: false,
+ beforeAddLiquidity: false,
+ afterAddLiquidity: false,
+ beforeRemoveLiquidity: false,
+ afterRemoveLiquidity: false,
+ beforeSwap: true,
+ afterSwap: false,
+ beforeDonate: false,
+ afterDonate: false,
+ noOp: false,
+ accessLock: false
+ });
+ }
+
+ function beforeSwap(address, PoolKey calldata key, IPoolManager.SwapParams calldata, bytes calldata)
+ external
+ override
+ returns (bytes4)
+ {
+
+ poolManager.updateDynamicSwapFee(key);
+ return BaseHook.beforeSwap.selector;
+ }
+}
+
`
+
+export default html
diff --git a/src/pages/fees/dynamic-fee/index.md b/src/pages/fees/dynamic-fee/index.md
new file mode 100644
index 00000000..b0ef5baf
--- /dev/null
+++ b/src/pages/fees/dynamic-fee/index.md
@@ -0,0 +1,59 @@
+---
+title: Dynamic Fees
+version: 0.8.20
+description: Design a v4 pool with a dynamic fee
+keywords: [fee, fees, dynamic fee, dynamic, poke]
+---
+
+- Design a v4 pool with a dynamic fee
+
+Uniswap v4 pools can support dynamic swap fees, and do not need to adhere to a static fee (0.05% / 0.30% / 1.0%). The hook needs to inherit `IDynamicFeeManager` and use `FeeLibrary.DYNAMIC_FEE_FLAG` in its `PoolKey.fee`.
+
+Despite its name, the fee is *cached* by the `PoolManager` and an external call `PoolManager.updateDynamicFee()` is required to change the swap fee.
+
+**Note: dynamic fees can be computed every swap, but incurs a gas overhead**
+
+---
+
+### Initialize a Dynamic Fee Pool
+
+```solidity
+import {FeeLibrary} from "v4-core/libraries/FeeLibrary.sol";
+
+
+poolKey = PoolKey(
+ Currency.wrap(address(token0)),
+ Currency.wrap(address(token1)),
+ FeeLibrary.DYNAMIC_FEE_FLAG, // signal that the pool has a dynamic fee
+ 60,
+ IHooks(hook)
+);
+initializeRouter.initialize(poolKey, startingPrice, hookData);
+```
+
+## Example: Manual Dynamic Fee
+
+*Implements a time-decaying dynamic fee*
+
+* The swap fee starts at 5.0%
+* The fee decays 0.00001% every second
+* After 495,000 seconds, the minimum fee is set to 0.05%
+
+
+1) Inherit `IDynamicFeeManager`
+2) Implement `getFee()`
+3) Poke `PoolManager.updateDynamicFee()` to change the fee
+```solidity
+{{{ManualDynamicFee}}}
+```
+
+## Example: Automatic Dynamic Fee
+
+*Implements an automatically-updated, time-decaying dynamic fee*
+
+The hook uses `beforeSwap` to automatically poke the PoolManager, ensuring the fee is always up-to-date
+
+*incurs +23,000 gas overhead*
+```solidity
+{{{AutoDynamicFee}}}
+```
diff --git a/src/pages/fees/dynamic-fee/index.tsx b/src/pages/fees/dynamic-fee/index.tsx
new file mode 100644
index 00000000..1c63a4f4
--- /dev/null
+++ b/src/pages/fees/dynamic-fee/index.tsx
@@ -0,0 +1,29 @@
+import React from "react"
+import Example from "../../../components/Example"
+import html, { version, title, description, codes } from "./index.html"
+
+interface Path {
+ path: string
+ title: string
+}
+
+interface Props {
+ prev: Path | null
+ next: Path | null
+}
+
+const ExamplePage: React.FC = ({ prev, next }) => {
+ return (
+
+ )
+}
+
+export default ExamplePage
diff --git a/src/pages/index.tsx b/src/pages/index.tsx
index bf408dfc..2bdaac71 100644
--- a/src/pages/index.tsx
+++ b/src/pages/index.tsx
@@ -8,7 +8,7 @@ import styles from "./index.module.css"
import youTube from "../components/youtube.png"
import { ROUTES, ROUTES_BY_CATEGORY, TRANSLATIONS } from "../nav"
-const UPDATES = ["2024/01/08 - Quoter", "2023/12/15 - Update v4", "2023/12/11 - Custom Curves", "2023/12/03 - Static Hook Fee", "2023/11/28 - Updated pool initialization", "2023/11/28 - NoOp", "2023/11/13 - Make snippets concise", "2023/10/18 - Initial V4 Snippets"]
+const UPDATES = ["2024/01/23 - Dynamic Fees", "2024/01/08 - Quoter", "2023/12/15 - Update v4", "2023/12/11 - Custom Curves", "2023/12/03 - Static Hook Fee", "2023/11/28 - Updated pool initialization", "2023/11/28 - NoOp", "2023/11/13 - Make snippets concise", "2023/10/18 - Initial V4 Snippets"]
export default function HomePage() {
const [query, setQuery] = useState("")
diff --git a/src/routes.tsx b/src/routes.tsx
index e87863ef..023ff0a0 100644
--- a/src/routes.tsx
+++ b/src/routes.tsx
@@ -1,4 +1,5 @@
import component_create_liquidity from "./pages/create-liquidity"
+import component_fees_dynamic_fee from "./pages/fees/dynamic-fee"
import component_fees_fixed_hook_fee from "./pages/fees/fixed-hook-fee"
import component_hooks_custom_curve from "./pages/hooks/custom-curve"
import component_hooks_no_op from "./pages/hooks/no-op"
@@ -28,6 +29,10 @@ const routes: Route[] = [
path: "/create-liquidity",
component: component_create_liquidity
},
+ {
+ path: "/fees/dynamic-fee",
+ component: component_fees_dynamic_fee
+ },
{
path: "/fees/fixed-hook-fee",
component: component_fees_fixed_hook_fee
diff --git a/src/search.json b/src/search.json
index a6562aa2..17493745 100644
--- a/src/search.json
+++ b/src/search.json
@@ -79,7 +79,8 @@
"/hooks/custom-curve"
],
"fee": [
- "/fees/fixed-hook-fee"
+ "/fees/fixed-hook-fee",
+ "/fees/dynamic-fee"
],
"static fee": [
"/fees/fixed-hook-fee"
@@ -87,6 +88,18 @@
"hook fee": [
"/fees/fixed-hook-fee"
],
+ "fees": [
+ "/fees/dynamic-fee"
+ ],
+ "dynamic fee": [
+ "/fees/dynamic-fee"
+ ],
+ "dynamic": [
+ "/fees/dynamic-fee"
+ ],
+ "poke": [
+ "/fees/dynamic-fee"
+ ],
"liquidity": [
"/create-liquidity"
],