diff --git a/contracts/identitytreestore/IdentityTreeStore.sol b/contracts/identitytreestore/IdentityTreeStore.sol
index 34bd4dd5..65002641 100644
--- a/contracts/identitytreestore/IdentityTreeStore.sol
+++ b/contracts/identitytreestore/IdentityTreeStore.sol
@@ -32,22 +32,15 @@ contract IdentityTreeStore is
     using ReverseHashLib for ReverseHashLib.Data;
 
     /// @custom:storage-location erc7201:iden3.storage.IdentityTreeStore.ReverseHashLibData
-    struct ReverseHashLibDataStorage {
-        ReverseHashLib.Data _data;
-    }
 
     // keccak256(abi.encode(uint256(keccak256("iden3.storage.IdentityTreeStore.ReverseHashLibData")) - 1)) &
     //    ~bytes32(uint256(0xff));
-    bytes32 private constant ReverseHashLibDataStorageLocation =
+    bytes32 private constant REVERSE_HASH_LIB_DATA_STORAGE_LOCATION =
         0x0f7e3bdc6cc0e880d509aa1f6b8d1a88e5fcb7274e18dfba772424a36fe9b400;
 
-    function _getReverseHashLibDataStorage()
-        private
-        pure
-        returns (ReverseHashLibDataStorage storage $)
-    {
+    function _getReverseHashLibDataStorage() private pure returns (ReverseHashLib.Data storage $) {
         assembly {
-            $.slot := ReverseHashLibDataStorageLocation
+            $.slot := REVERSE_HASH_LIB_DATA_STORAGE_LOCATION
         }
     }
 
@@ -57,18 +50,18 @@ contract IdentityTreeStore is
     }
 
     // keccak256(abi.encode(uint256(keccak256("iden3.storage.IdentityTreeStore.Main")) - 1)) & ~bytes32(uint256(0xff));
-    bytes32 private constant MainStorageLocation =
+    bytes32 private constant MAIN_STORAGE_LOCATION =
         0x95ca427007e091a13a7ccfcb233b8a2ed19d987330a248c445b1b483a35bb800;
 
     function _getMainStorage() private pure returns (MainStorage storage $) {
         assembly {
-            $.slot := MainStorageLocation
+            $.slot := MAIN_STORAGE_LOCATION
         }
     }
 
     function initialize(address state) public initializer {
         _getMainStorage()._state = IState(state);
-        _getReverseHashLibDataStorage()._data.hashFunction = _hashFunc;
+        _getReverseHashLibDataStorage().hashFunction = _hashFunc;
     }
 
     /**
@@ -76,7 +69,7 @@ contract IdentityTreeStore is
      * @param nodes An array of nodes
      */
     function saveNodes(uint256[][] memory nodes) external {
-        return _getReverseHashLibDataStorage()._data.savePreimages(nodes);
+        return _getReverseHashLibDataStorage().savePreimages(nodes);
     }
 
     /**
@@ -85,7 +78,7 @@ contract IdentityTreeStore is
      * @return The node
      */
     function getNode(uint256 key) public view returns (uint256[] memory) {
-        uint256[] memory preim = _getReverseHashLibDataStorage()._data.getPreimage(key);
+        uint256[] memory preim = _getReverseHashLibDataStorage().getPreimage(key);
         require(preim.length > 0, "Node not found");
         return preim;
     }
@@ -160,10 +153,10 @@ contract IdentityTreeStore is
         uint256 nextNodeHash = root;
         uint256[] memory children;
 
-        ReverseHashLibDataStorage storage $ = _getReverseHashLibDataStorage();
+        ReverseHashLib.Data storage $ = _getReverseHashLibDataStorage();
 
         for (uint256 i = 0; i <= MAX_SMT_DEPTH; i++) {
-            children = $._data.hashesToPreimages[nextNodeHash];
+            children = $.hashesToPreimages[nextNodeHash];
 
             NodeType nodeType = _nodeType(children);
             if (nodeType == NodeType.Empty) {