diff --git a/contracts/interfaces/IEVMWriter.sol b/contracts/interfaces/IEVMWriter.sol
index 575a7b4..02f14ad 100644
--- a/contracts/interfaces/IEVMWriter.sol
+++ b/contracts/interfaces/IEVMWriter.sol
@@ -1,7 +1,7 @@
 // SPDX-License-Identifier: UNLICENSED
 pragma solidity ^0.8.9;
 
-interface IEvmWriter {
+interface IEVMWriter {
     function setBalance(address acc, uint256 value) external;
 
     function copyCode(address acc, address from) external;
diff --git a/contracts/sfc/NodeDriverI.sol b/contracts/interfaces/INodeDriver.sol
similarity index 97%
rename from contracts/sfc/NodeDriverI.sol
rename to contracts/interfaces/INodeDriver.sol
index fdabbec..a8519de 100644
--- a/contracts/sfc/NodeDriverI.sol
+++ b/contracts/interfaces/INodeDriver.sol
@@ -1,7 +1,7 @@
 // SPDX-License-Identifier: UNLICENSED
 pragma solidity ^0.8.9;
 
-interface NodeDriverI {
+interface INodeDriver {
     function setGenesisValidator(
         address _auth,
         uint256 validatorID,
diff --git a/contracts/interfaces/INodeDriverExecutable.sol b/contracts/interfaces/INodeDriverExecutable.sol
new file mode 100644
index 0000000..9bc78cc
--- /dev/null
+++ b/contracts/interfaces/INodeDriverExecutable.sol
@@ -0,0 +1,6 @@
+// SPDX-License-Identifier: UNLICENSED
+pragma solidity ^0.8.9;
+
+interface INodeDriverExecutable {
+    function execute() external;
+}
diff --git a/contracts/sfc/SFCI.sol b/contracts/interfaces/ISFC.sol
similarity index 99%
rename from contracts/sfc/SFCI.sol
rename to contracts/interfaces/ISFC.sol
index 39bd84c..aae9bd9 100644
--- a/contracts/sfc/SFCI.sol
+++ b/contracts/interfaces/ISFC.sol
@@ -1,7 +1,7 @@
 // SPDX-License-Identifier: UNLICENSED
 pragma solidity ^0.8.9;
 
-interface SFCI {
+interface ISFC {
     event CreatedValidator(
         uint256 indexed validatorID,
         address indexed auth,
diff --git a/contracts/sfc/NetworkInitializer.sol b/contracts/sfc/NetworkInitializer.sol
index d205dd4..fe08295 100644
--- a/contracts/sfc/NetworkInitializer.sol
+++ b/contracts/sfc/NetworkInitializer.sol
@@ -1,7 +1,7 @@
 // SPDX-License-Identifier: UNLICENSED
 pragma solidity ^0.8.9;
 
-import {SFCI} from "./SFCI.sol";
+import {ISFC} from "../interfaces/ISFC.sol";
 import {NodeDriver, NodeDriverAuth} from "./NodeDriver.sol";
 import {ConstantsManager} from "./ConstantsManager.sol";
 import {Decimal} from "../common/Decimal.sol";
@@ -37,6 +37,6 @@ contract NetworkInitializer {
         consts.updateGasPriceBalancingCounterweight(3600);
         consts.transferOwnership(_owner);
 
-        SFCI(_sfc).initialize(sealedEpoch, totalSupply, _auth, _lib, address(consts), _owner);
+        ISFC(_sfc).initialize(sealedEpoch, totalSupply, _auth, _lib, address(consts), _owner);
     }
 }
diff --git a/contracts/sfc/NodeDriver.sol b/contracts/sfc/NodeDriver.sol
index ad15cae..99f1a69 100644
--- a/contracts/sfc/NodeDriver.sol
+++ b/contracts/sfc/NodeDriver.sol
@@ -3,11 +3,11 @@ pragma solidity ^0.8.9;
 
 import {Initializable} from "../common/Initializable.sol";
 import {NodeDriverAuth} from "./NodeDriverAuth.sol";
-import {IEvmWriter} from "../interfaces/IEVMWriter.sol";
+import {IEVMWriter} from "../interfaces/IEVMWriter.sol";
 
 contract NodeDriver is Initializable {
     NodeDriverAuth internal backend;
-    IEvmWriter internal evmWriter;
+    IEVMWriter internal evmWriter;
 
     error NotNode();
     error NotBackend();
@@ -36,7 +36,7 @@ contract NodeDriver is Initializable {
     function initialize(address _backend, address _evmWriterAddress) external initializer {
         backend = NodeDriverAuth(_backend);
         emit UpdatedBackend(_backend);
-        evmWriter = IEvmWriter(_evmWriterAddress);
+        evmWriter = IEVMWriter(_evmWriterAddress);
     }
 
     function setBalance(address acc, uint256 value) external onlyBackend {
diff --git a/contracts/sfc/NodeDriverAuth.sol b/contracts/sfc/NodeDriverAuth.sol
index 444aafe..eab3348 100644
--- a/contracts/sfc/NodeDriverAuth.sol
+++ b/contracts/sfc/NodeDriverAuth.sol
@@ -3,15 +3,12 @@ pragma solidity ^0.8.9;
 
 import {Initializable} from "../common/Initializable.sol";
 import {Ownable} from "../ownership/Ownable.sol";
-import {SFCI} from "./SFCI.sol";
+import {ISFC} from "../interfaces/ISFC.sol";
 import {NodeDriver} from "./NodeDriver.sol";
-
-interface NodeDriverExecutable {
-    function execute() external;
-}
+import {INodeDriverExecutable} from "../interfaces/INodeDriverExecutable.sol";
 
 contract NodeDriverAuth is Initializable, Ownable {
-    SFCI internal sfc;
+    ISFC internal sfc;
     NodeDriver internal driver;
 
     error NotSFC();
@@ -25,7 +22,7 @@ contract NodeDriverAuth is Initializable, Ownable {
     function initialize(address payable _sfc, address _driver, address _owner) external initializer {
         Ownable.initialize(_owner);
         driver = NodeDriver(_driver);
-        sfc = SFCI(_sfc);
+        sfc = ISFC(_sfc);
     }
 
     modifier onlySFC() {
@@ -48,7 +45,7 @@ contract NodeDriverAuth is Initializable, Ownable {
 
     function _execute(address executable, address newOwner, bytes32 selfCodeHash, bytes32 driverCodeHash) internal {
         _transferOwnership(executable);
-        NodeDriverExecutable(executable).execute();
+        INodeDriverExecutable(executable).execute();
         _transferOwnership(newOwner);
         //require(driver.backend() == address(this), "ownership of driver is lost");
         if (_getCodeHash(address(this)) != selfCodeHash) {
diff --git a/contracts/sfc/Updater.sol b/contracts/sfc/Updater.sol
index 5085a8d..46c93b3 100644
--- a/contracts/sfc/Updater.sol
+++ b/contracts/sfc/Updater.sol
@@ -6,7 +6,7 @@ import {Decimal} from "../common/Decimal.sol";
 import {NodeDriverAuth} from "./NodeDriverAuth.sol";
 import {ConstantsManager} from "./ConstantsManager.sol";
 import {SFC} from "./SFC.sol";
-import {SFCI} from "./SFCI.sol";
+import {ISFC} from "../interfaces/ISFC.sol";
 import {Version} from "../version/Version.sol";
 
 interface GovI {
@@ -101,8 +101,8 @@ contract Updater {
 
         NodeDriverAuth nodeAuth = NodeDriverAuth(0xD100ae0000000000000000000000000000000000);
         nodeAuth.upgradeCode(sfcTo, sfcFrom);
-        SFCI(sfcTo).updateConstsAddress(sfcConsts);
-        SFCI(sfcTo).updateVoteBookAddress(voteBook);
+        ISFC(sfcTo).updateConstsAddress(sfcConsts);
+        ISFC(sfcTo).updateVoteBookAddress(voteBook);
         SFC(sfcTo).updateLibAddress(sfcLib);
 
         nodeAuth.upgradeCode(govTo, govFrom);
diff --git a/contracts/test/StubEvmWriter.sol b/contracts/test/StubEvmWriter.sol
index 1c50617..20f03fc 100644
--- a/contracts/test/StubEvmWriter.sol
+++ b/contracts/test/StubEvmWriter.sol
@@ -1,9 +1,9 @@
 // SPDX-License-Identifier: UNLICENSED
 pragma solidity ^0.8.9;
 
-import {IEvmWriter} from "../interfaces/IEVMWriter.sol";
+import {IEVMWriter} from "../interfaces/IEVMWriter.sol";
 
-contract StubEvmWriter is IEvmWriter {
+contract StubEvmWriter is IEVMWriter {
     function setBalance(address acc, uint256 value) external {}
 
     function copyCode(address acc, address from) external {}