diff --git a/contracts/ERC165/ERC165Removable.sol b/contracts/ERC165/ERC165Removable.sol
index b943b20..e593e6d 100644
--- a/contracts/ERC165/ERC165Removable.sol
+++ b/contracts/ERC165/ERC165Removable.sol
@@ -1,5 +1,6 @@
 // SPDX-License-Identifier: MIT;
-pragma solidity 0.6.2;
+
+pragma solidity ^0.6.6;
 
 import "./IERC165.sol";
 
diff --git a/contracts/ERC165/IERC165.sol b/contracts/ERC165/IERC165.sol
index 425458d..158dfb4 100644
--- a/contracts/ERC165/IERC165.sol
+++ b/contracts/ERC165/IERC165.sol
@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: MIT
 
-pragma solidity ^0.6.0;
+pragma solidity ^0.6.6;
 
 /**
  * @dev Interface of the ERC165 standard, as defined in the
diff --git a/package.json b/package.json
index a00e0e5..7087600 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@windingtree/smart-contracts-libraries",
-  "version": "0.1.3",
+  "version": "0.1.4",
   "description": "Libraries and utilities for smart contracts",
   "publishConfig": {
     "access": "public"
@@ -27,9 +27,7 @@
     "url": "https://github.com/windingtree/smart-contracts-libraries/issues"
   },
   "homepage": "https://github.com/windingtree/smart-contracts-libraries#readme",
-  "dependencies": {
-    "@openzeppelin/contracts": "3.2.0"
-  },
+  "dependencies": {},
   "devDependencies": {
     "solc": "0.7.4",
     "solhint": "3.3.2",
diff --git a/truffle.js b/truffle.js
index aecfe31..5d45077 100644
--- a/truffle.js
+++ b/truffle.js
@@ -44,7 +44,7 @@ module.exports = {
 
     compilers: {
         solc: {
-            version: '0.6.2',
+            version: '0.6.6',
             settings: {
                 optimizer: {
                     enabled: true,