diff --git a/.vscode/settings.json b/.vscode/settings.json
index 9badf5e..1b0ce30 100644
--- a/.vscode/settings.json
+++ b/.vscode/settings.json
@@ -4,5 +4,5 @@
   "solidity.packageDefaultDependenciesContractsDirectory": "src",
   "diffEditor.ignoreTrimWhitespace": false,
   "editor.trimAutoWhitespace": true,
-  "solidity.compileUsingRemoteVersion": "v0.8.17+commit.8df45f5f"
+  "solidity.compileUsingRemoteVersion": "v0.8.21+commit.d9974be"
 }
diff --git a/foundry.toml b/foundry.toml
index 3eee27c..d1f7bde 100644
--- a/foundry.toml
+++ b/foundry.toml
@@ -3,6 +3,10 @@ src = 'src'
 out = 'out'
 libs = ['lib']
 verbosity = 3
+solc-version = '0.8.21'
+via_ir = true
+optimizer = true
+optimizer_runs = 1000000000
 
 remappings = [
     'forge-std/=lib/forge-std/src/',
diff --git a/script/DeployCometWrapper.s.sol b/script/DeployCometWrapper.s.sol
index 59a6886..b1522ae 100644
--- a/script/DeployCometWrapper.s.sol
+++ b/script/DeployCometWrapper.s.sol
@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: MIT
-pragma solidity 0.8.17;
+pragma solidity 0.8.21;
 
 import "forge-std/Script.sol";
 import "forge-std/console.sol";
diff --git a/src/CometHelpers.sol b/src/CometHelpers.sol
index 5a84ead..90edf15 100644
--- a/src/CometHelpers.sol
+++ b/src/CometHelpers.sol
@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: MIT
-pragma solidity 0.8.17;
+pragma solidity 0.8.21;
 
 import {CometMath} from "./vendor/CometMath.sol";
 
diff --git a/src/CometWrapper.sol b/src/CometWrapper.sol
index 5100cb9..bce97af 100644
--- a/src/CometWrapper.sol
+++ b/src/CometWrapper.sol
@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: MIT
-pragma solidity 0.8.17;
+pragma solidity 0.8.21;
 
 import { ERC4626 } from "solmate/mixins/ERC4626.sol";
 import { ERC20 } from "solmate/tokens/ERC20.sol";
diff --git a/src/vendor/CometExtInterface.sol b/src/vendor/CometExtInterface.sol
index 14e32f5..836c8c4 100644
--- a/src/vendor/CometExtInterface.sol
+++ b/src/vendor/CometExtInterface.sol
@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: BUSL-1.1
-pragma solidity 0.8.17;
+pragma solidity 0.8.21;
 
 struct TotalsBasic {
     uint64 baseSupplyIndex;
diff --git a/src/vendor/CometInterface.sol b/src/vendor/CometInterface.sol
index ae7bd9d..e72456d 100644
--- a/src/vendor/CometInterface.sol
+++ b/src/vendor/CometInterface.sol
@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: BUSL-1.1
-pragma solidity 0.8.17;
+pragma solidity 0.8.21;
 
 import "./CometMainInterface.sol";
 import "./CometExtInterface.sol";
diff --git a/src/vendor/CometMainInterface.sol b/src/vendor/CometMainInterface.sol
index 41b1bc9..8ac65ed 100644
--- a/src/vendor/CometMainInterface.sol
+++ b/src/vendor/CometMainInterface.sol
@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: BUSL-1.1
-pragma solidity 0.8.17;
+pragma solidity 0.8.21;
 
 struct AssetInfo {
     uint8 offset;
diff --git a/src/vendor/CometMath.sol b/src/vendor/CometMath.sol
index 0dfe846..4baab1e 100644
--- a/src/vendor/CometMath.sol
+++ b/src/vendor/CometMath.sol
@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: BUSL-1.1
-pragma solidity 0.8.17;
+pragma solidity 0.8.21;
 
 /**
  * @title Compound's Comet Math Contract
diff --git a/src/vendor/ICometConfigurator.sol b/src/vendor/ICometConfigurator.sol
index d67e9cc..da41066 100644
--- a/src/vendor/ICometConfigurator.sol
+++ b/src/vendor/ICometConfigurator.sol
@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: MIT
-pragma solidity 0.8.17;
+pragma solidity 0.8.21;
 
 interface ICometConfigurator {
     struct Configuration {
diff --git a/src/vendor/ICometRewards.sol b/src/vendor/ICometRewards.sol
index ddce729..0c93bd4 100644
--- a/src/vendor/ICometRewards.sol
+++ b/src/vendor/ICometRewards.sol
@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: ISC
-pragma solidity 0.8.17;
+pragma solidity 0.8.21;
 
 interface ICometRewards {
     struct RewardConfig {
diff --git a/test/BaseUSDbCTest.t.sol b/test/BaseUSDbCTest.t.sol
index cc1fb1c..99ca305 100644
--- a/test/BaseUSDbCTest.t.sol
+++ b/test/BaseUSDbCTest.t.sol
@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: MIT
-pragma solidity 0.8.17;
+pragma solidity 0.8.21;
 
 import { Test } from "forge-std/Test.sol";
 import { CometWrapper, CometInterface, ICometRewards, CometHelpers, ERC20 } from "../src/CometWrapper.sol";
diff --git a/test/CometWrapper.t.sol b/test/CometWrapper.t.sol
index 9eb2413..0ec80cf 100644
--- a/test/CometWrapper.t.sol
+++ b/test/CometWrapper.t.sol
@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: MIT
-pragma solidity 0.8.17;
+pragma solidity 0.8.21;
 
 import { CoreTest, CometHelpers, CometWrapper, ERC20, ICometRewards } from "./CoreTest.sol";
 import { CometMath } from "../src/vendor/CometMath.sol";
@@ -950,5 +950,4 @@ abstract contract CometWrapperTest is CoreTest, CometMath {
 }
 
 // TODO: add fuzz testing for withdraw
-// TODO: add tests for cWETHv3 decimals
 // TODO: add tests for max withdraw/redeem
diff --git a/test/CometWrapperInvariant.t.sol b/test/CometWrapperInvariant.t.sol
index 8502f0c..fa3a94a 100644
--- a/test/CometWrapperInvariant.t.sol
+++ b/test/CometWrapperInvariant.t.sol
@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: MIT
-pragma solidity 0.8.17;
+pragma solidity 0.8.21;
 
 import { CoreTest, CometHelpers, CometWrapper, ERC20, ICometRewards } from "./CoreTest.sol";
 import { CometMath } from "../src/vendor/CometMath.sol";
diff --git a/test/CoreTest.sol b/test/CoreTest.sol
index 90169b8..ea86764 100644
--- a/test/CoreTest.sol
+++ b/test/CoreTest.sol
@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: MIT
-pragma solidity 0.8.17;
+pragma solidity 0.8.21;
 
 import { Test } from "forge-std/Test.sol";
 import { CometWrapper, CometInterface, ICometRewards, CometHelpers, ERC20 } from "../src/CometWrapper.sol";
diff --git a/test/MainnetUSDCTest.t.sol b/test/MainnetUSDCTest.t.sol
index c0fe128..8f0b206 100644
--- a/test/MainnetUSDCTest.t.sol
+++ b/test/MainnetUSDCTest.t.sol
@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: MIT
-pragma solidity 0.8.17;
+pragma solidity 0.8.21;
 
 import { Test } from "forge-std/Test.sol";
 import { CometWrapper, CometInterface, ICometRewards, CometHelpers, ERC20 } from "../src/CometWrapper.sol";
diff --git a/test/MainnetWETHTest.t.sol b/test/MainnetWETHTest.t.sol
index 054d5cf..e7392cf 100644
--- a/test/MainnetWETHTest.t.sol
+++ b/test/MainnetWETHTest.t.sol
@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: MIT
-pragma solidity 0.8.17;
+pragma solidity 0.8.21;
 
 import { Test } from "forge-std/Test.sol";
 import { CometWrapper, CometInterface, ICometRewards, CometHelpers, ERC20 } from "../src/CometWrapper.sol";
diff --git a/test/Rewards.t.sol b/test/Rewards.t.sol
index 3ae2bd6..386e239 100644
--- a/test/Rewards.t.sol
+++ b/test/Rewards.t.sol
@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: MIT
-pragma solidity 0.8.17;
+pragma solidity 0.8.21;
 
 import { CoreTest } from "./CoreTest.sol";
 import { CometWrapper, ICometRewards, CometHelpers, ERC20 } from "../src/CometWrapper.sol";
@@ -285,5 +285,3 @@ abstract contract RewardsTest is CoreTest {
         vm.stopPrank();
     }
 }
-
-// TODO: test cWETHv3