diff --git a/.prettierignore b/.prettierignore
index 5e3a4f1a7a..2f8b5df737 100644
--- a/.prettierignore
+++ b/.prettierignore
@@ -60,6 +60,7 @@ lib
 /contracts/dev-utils/test/generated-wrappers
 /contracts/dev-utils/generated-artifacts
 /contracts/dev-utils/test/generated-artifacts
+/contracts/zero-ex/foundry-artifacts
 /contracts/zero-ex/generated-wrappers
 /contracts/zero-ex/test/generated-wrappers
 /contracts/zero-ex/generated-artifacts
diff --git a/contracts/zero-ex/contracts/src/transformers/AffiliateFeeTransformer.sol b/contracts/zero-ex/contracts/src/transformers/AffiliateFeeTransformer.sol
index 7efcb45931..d24a98eb80 100644
--- a/contracts/zero-ex/contracts/src/transformers/AffiliateFeeTransformer.sol
+++ b/contracts/zero-ex/contracts/src/transformers/AffiliateFeeTransformer.sol
@@ -61,7 +61,7 @@ contract AffiliateFeeTransformer is Transformer {
                 amount = LibERC20Transformer.getTokenBalanceOf(fees[i].token, address(this));
             }
             if (amount != 0) {
-                fees[i].token.transformerTransfer(fees[i].recipient, amount);
+                fees[i].token.unsafeTransformerTransfer(fees[i].recipient, amount);
             }
         }
 
diff --git a/contracts/zero-ex/contracts/src/transformers/LibERC20Transformer.sol b/contracts/zero-ex/contracts/src/transformers/LibERC20Transformer.sol
index 5c24743bd3..effc38d9e2 100644
--- a/contracts/zero-ex/contracts/src/transformers/LibERC20Transformer.sol
+++ b/contracts/zero-ex/contracts/src/transformers/LibERC20Transformer.sol
@@ -34,7 +34,9 @@ library LibERC20Transformer {
     ///      This is just `keccak256('TRANSFORMER_SUCCESS')`.
     bytes4 internal constant TRANSFORMER_SUCCESS = 0x13c9929e;
 
-    /// @dev Transfer ERC20 tokens and ETH.
+    /// @dev Transfer ERC20 tokens and ETH. Since it relies on `transfer` it may run out of gas when
+    /// the `recipient` is a smart contract wallet. See `unsafeTransformerTransfer` for smart contract
+    /// compatible transfer.
     /// @param token An ERC20 or the ETH pseudo-token address (`ETH_TOKEN_ADDRESS`).
     /// @param to The recipient.
     /// @param amount The transfer amount.
@@ -50,6 +52,24 @@ library LibERC20Transformer {
         }
     }
 
+    /// @dev Transfer ERC20 tokens and ETH. For ETH transfer. It's not safe from re-entrancy attacks and the
+    /// caller is responsible for gurading against a potential re-entrancy attack.
+    /// @param token An ERC20 or the ETH pseudo-token address (`ETH_TOKEN_ADDRESS`).
+    /// @param to The recipient.
+    /// @param amount The transfer amount.
+    function unsafeTransformerTransfer(
+        IERC20TokenV06 token,
+        address payable to,
+        uint256 amount
+    ) internal {
+        if (isTokenETH(token)) {
+            (bool sent, ) = to.call{value: amount}("");
+            require(sent, "LibERC20Transformer/FAILED_TO_SEND_ETHER");
+        } else {
+            token.compatTransfer(to, amount);
+        }
+    }
+
     /// @dev Check if a token is the ETH pseudo-token.
     /// @param token The token to check.
     /// @return isETH `true` if the token is the ETH pseudo-token.
diff --git a/contracts/zero-ex/contracts/src/transformers/PayTakerTransformer.sol b/contracts/zero-ex/contracts/src/transformers/PayTakerTransformer.sol
index dad74f7355..eddf58d1a5 100644
--- a/contracts/zero-ex/contracts/src/transformers/PayTakerTransformer.sol
+++ b/contracts/zero-ex/contracts/src/transformers/PayTakerTransformer.sol
@@ -65,7 +65,7 @@ contract PayTakerTransformer is Transformer {
                 amount = data.tokens[i].getTokenBalanceOf(address(this));
             }
             if (amount != 0) {
-                data.tokens[i].transformerTransfer(context.recipient, amount);
+                data.tokens[i].unsafeTransformerTransfer(context.recipient, amount);
             }
         }
         return LibERC20Transformer.TRANSFORMER_SUCCESS;
diff --git a/contracts/zero-ex/contracts/src/transformers/PositiveSlippageFeeTransformer.sol b/contracts/zero-ex/contracts/src/transformers/PositiveSlippageFeeTransformer.sol
index 9cc1eff74d..651dd960c0 100644
--- a/contracts/zero-ex/contracts/src/transformers/PositiveSlippageFeeTransformer.sol
+++ b/contracts/zero-ex/contracts/src/transformers/PositiveSlippageFeeTransformer.sol
@@ -53,7 +53,7 @@ contract PositiveSlippageFeeTransformer is Transformer {
         uint256 transformerAmount = LibERC20Transformer.getTokenBalanceOf(fee.token, address(this));
         if (transformerAmount > fee.bestCaseAmount) {
             uint256 positiveSlippageAmount = transformerAmount - fee.bestCaseAmount;
-            fee.token.transformerTransfer(fee.recipient, positiveSlippageAmount);
+            fee.token.unsafeTransformerTransfer(fee.recipient, positiveSlippageAmount);
         }
 
         return LibERC20Transformer.TRANSFORMER_SUCCESS;