Disable initializers to be called directly

contracts/sfc/NodeDriver.sol

@@ -35,6 +35,11 @@ contract NodeDriver is OwnableUpgradeable, UUPSUpgradeable, INodeDriver {
     event UpdateNetworkVersion(uint256 version);
     event AdvanceEpochs(uint256 num);
 
+    /// @custom:oz-upgrades-unsafe-allow constructor
+    constructor() {
+        _disableInitializers();
+    }
+
     /// Initialization is called only once, after the contract deployment.
     /// Because the contract code is written directly into genesis, constructor cannot be used.
     function initialize(address _backend, address _evmWriterAddress, address _owner) external initializer {

contracts/sfc/NodeDriverAuth.sol

@@ -21,6 +21,11 @@ contract NodeDriverAuth is OwnableUpgradeable, UUPSUpgradeable {
     error DriverCodeHashMismatch();
     error RecipientNotSFC();
 
+    /// @custom:oz-upgrades-unsafe-allow constructor
+    constructor() {
+        _disableInitializers();
+    }
+
     // Initialize NodeDriverAuth, NodeDriver and SFC in one call to allow fewer genesis transactions
     function initialize(address payable _sfc, address _driver, address _owner) external initializer {
         __Ownable_init(_owner);

contracts/sfc/SFC.sol

@@ -229,6 +229,11 @@ contract SFC is OwnableUpgradeable, UUPSUpgradeable, Version {
         _;
     }
 
+    /// @custom:oz-upgrades-unsafe-allow constructor
+    constructor() {
+        _disableInitializers();
+    }
+
     /// Initialization is called only once, after the contract deployment.
     /// Because the contract code is written directly into genesis, constructor cannot be used.
     function initialize(