diff --git a/contracts/deploy/DelayedUpdatableInstance.sol b/contracts/deploy/DelayedUpdatableInstance.sol
index 3ff6b0f..405a999 100644
--- a/contracts/deploy/DelayedUpdatableInstance.sol
+++ b/contracts/deploy/DelayedUpdatableInstance.sol
@@ -1,4 +1,4 @@
-pragma solidity ^0.4.17;
+pragma solidity ^0.4.21;
 
 import "./DelayedUpdatableInstanceStorage.sol";
 import "./DelegatedCall.sol";
@@ -22,42 +22,56 @@ contract DelayedUpdatableInstance is DelayedUpdatableInstanceStorage, DelegatedC
      * @dev delegatecall everything (but declared functions) to `_target()`
      * @notice Verify `kernel()` code to predict behavior
      */
-    function () external delegated {
+    function () 
+        external 
+        delegated 
+    {
         //all goes to kernel
     }
 
+    function updateRequestUpdatableInstance(
+        address _kernel
+    ) 
+        external
+    {
+        require(msg.sender == address(this));
+        uint activation = block.timestamp + 30 days;
+        update = Update(_kernel, activation);
+        emit UpdateRequested(_kernel, activation);
+    }
+
+    function updateConfirmUpdatableInstance(
+        address _kernel
+    )
+        external
+    {
+        require(msg.sender == address(this));
+        Update memory pending = update;
+        require(pending.kernel == _kernel);
+        require(pending.activation < block.timestamp);
+        kernel = pending.kernel;
+        delete update;
+        emit UpdateConfirmed(kernel, pending.kernel);
+    }
+
+    function updateCancelUpdatableInstance() 
+        external
+    {
+        require(msg.sender == address(this));
+        delete update;
+    }
+
     /**
      * @dev returns configured kernel
      * @return kernel address
      */
     function targetDelegatedCall()
         internal
-        constant
+        view
         returns(address)
     {
         return kernel;
     }
     
-    function updateRequestUpdatableInstance(address _kernel) external {
-        require(msg.sender == address(this));
-        uint activation = block.timestamp + 30 days;
-        update = Update(_kernel, activation);
-        UpdateRequested(_kernel, activation);
-    }
-
-    function updateConfirmUpdatableInstance(address _kernel) external {
-        require(msg.sender == address(this));
-        Update memory pending = update;
-        require(pending.kernel == _kernel);
-        require(pending.activation < block.timestamp);
-        kernel = pending.kernel;
-        delete update;
-        UpdateConfirmed(kernel, pending.kernel);
-    }
-
-    function updateCancelUpdatableInstance() external {
-        require(msg.sender == address(this));
-        delete update;
-    }
 
 }
\ No newline at end of file
diff --git a/contracts/identity/ERC725.sol b/contracts/identity/ERC725.sol
index 17af37a..696d50d 100644
--- a/contracts/identity/ERC725.sol
+++ b/contracts/identity/ERC725.sol
@@ -1,4 +1,4 @@
-pragma solidity ^0.4.18;
+pragma solidity ^0.4.21;
 
 contract ERC725 {
 
@@ -19,9 +19,9 @@ contract ERC725 {
         bytes32 key;
     }
 
-    function getKey(bytes32 _key, uint256 _purpose) public constant returns(uint256 purpose, uint256 keyType, bytes32 key);
-    function getKeyPurpose(bytes32 _key) public constant returns(uint256[] purpose);
-    function getKeysByPurpose(uint256 _purpose) public constant returns(bytes32[] keys);
+    function getKey(bytes32 _key, uint256 _purpose) public view returns(uint256 purpose, uint256 keyType, bytes32 key);
+    function getKeyPurpose(bytes32 _key) public view returns(uint256[] purpose);
+    function getKeysByPurpose(uint256 _purpose) public view returns(bytes32[] keys);
     function addKey(bytes32 _key, uint256 _purpose, uint256 _keyType) public returns (bool success);
     function removeKey(bytes32 _key, uint256 _purpose) public returns (bool success);
     function execute(address _to, uint256 _value, bytes _data) public returns (uint256 executionId);
diff --git a/contracts/identity/ERC735.sol b/contracts/identity/ERC735.sol
index 2109d28..8891552 100644
--- a/contracts/identity/ERC735.sol
+++ b/contracts/identity/ERC735.sol
@@ -1,4 +1,4 @@
-pragma solidity ^0.4.18;
+pragma solidity ^0.4.21;
 
 contract ERC735 {
 
@@ -16,8 +16,8 @@ contract ERC735 {
         string uri;
     }
 
-    function getClaim(bytes32 _claimId) public constant returns(uint256 claimType, uint256 scheme, address issuer, bytes signature, bytes data, string uri);
-    function getClaimIdsByType(uint256 _claimType) public constant returns(bytes32[] claimIds);
+    function getClaim(bytes32 _claimId) public view returns(uint256 claimType, uint256 scheme, address issuer, bytes signature, bytes data, string uri);
+    function getClaimIdsByType(uint256 _claimType) public view returns(bytes32[] claimIds);
     function addClaim(uint256 _claimType, uint256 _scheme, address _issuer, bytes _signature, bytes _data, string _uri) public returns (bytes32 claimRequestId);
     function removeClaim(bytes32 _claimId) public returns (bool success);
 }
\ No newline at end of file
diff --git a/contracts/identity/Identity.sol b/contracts/identity/Identity.sol
index ceea2a9..962c442 100644
--- a/contracts/identity/Identity.sol
+++ b/contracts/identity/Identity.sol
@@ -1,4 +1,4 @@
-pragma solidity ^0.4.17;
+pragma solidity ^0.4.21;
 
 import "./ERC725.sol";
 import "./ERC735.sol";
@@ -283,7 +283,7 @@ contract Identity is ERC725, ERC735 {
         uint256 _purpose
     ) 
         public 
-        constant 
+        view 
         returns(uint256 purpose, uint256 keyType, bytes32 key) 
     {
         Key storage myKey = keys[keccak256(_key, _purpose)];
@@ -292,7 +292,7 @@ contract Identity is ERC725, ERC735 {
     
     function isKeyPurpose(bytes32 _key, uint256 _purpose) 
         public
-        constant 
+        view 
         returns (bool)
     {
         return keys[keccak256(_key, _purpose)].purpose == _purpose;
@@ -300,7 +300,7 @@ contract Identity is ERC725, ERC735 {
 
     function getKeyPurpose(bytes32 _key)
         public 
-        constant 
+        view 
         returns(uint256[] purpose)
     {
         
@@ -337,7 +337,7 @@ contract Identity is ERC725, ERC735 {
     
     function getKeysByPurpose(uint256 _purpose)
         public
-        constant
+        view
         returns(bytes32[])
     {
         return keysByPurpose[_purpose];
@@ -345,7 +345,7 @@ contract Identity is ERC725, ERC735 {
     
     function getClaim(bytes32 _claimId)
         public
-        constant 
+        view 
         returns(
             uint256 claimType,
             uint256 scheme,
@@ -361,7 +361,7 @@ contract Identity is ERC725, ERC735 {
     
     function getClaimIdsByType(uint256 _claimType)
         public
-        constant
+        view
         returns(bytes32[] claimIds)
     {
         return claimsByType[_claimType];