diff --git a/system-contracts/contracts/EvmInterpreter.yul b/system-contracts/contracts/EvmInterpreter.yul
index 077560eb2..be21b7d12 100644
--- a/system-contracts/contracts/EvmInterpreter.yul
+++ b/system-contracts/contracts/EvmInterpreter.yul
@@ -346,16 +346,22 @@ object "EVMInterpreter" {
         function _fetchDeployedCodeLen(addr) -> codeLen {
             let codeHash := _getRawCodeHash(addr)
         
-            switch shr(248, codeHash)
+            mstore(0, codeHash)
+        
+            let success := staticcall(gas(), CODE_ORACLE_SYSTEM_CONTRACT(), 0, 32, 0, 0)
+        
+            switch iszero(success)
             case 1 {
-                // EraVM
-                let codeLengthInWords := and(shr(224, codeHash), 0xffff)
-                codeLen := shl(5, codeLengthInWords) // codeLengthInWords * 32
+                // The code oracle call can only fail in the case where the contract
+                // we are querying is the current one executing and it has not yet been
+                // deployed, i.e., if someone calls codesize (or extcodesize(address()))
+                // inside the constructor. In that case, code length is zero.
+                codeLen := 0
             }
-            case 2 {
-                // EVM
-                let codeLengthInBytes := and(shr(224, codeHash), 0xffff)
-                codeLen := codeLengthInBytes
+            default {
+                // The first word is the true length of the bytecode
+                returndatacopy(0, 0, 32)
+                codeLen := mload(0)
             }
         }
         
@@ -2040,7 +2046,9 @@ object "EVMInterpreter" {
                         evmGasLeft := chargeGas(evmGasLeft, 2500)
                     }
             
-                    sp := pushStackItemWithoutCheck(sp, _fetchDeployedCodeLen(addr))
+                    switch _isEVM(addr) 
+                        case 0  { sp := pushStackItemWithoutCheck(sp, extcodesize(addr)) }
+                        default { sp := pushStackItemWithoutCheck(sp, _fetchDeployedCodeLen(addr)) }
                     ip := add(ip, 1)
                 }
                 case 0x3C { // OP_EXTCODECOPY
@@ -3320,16 +3328,22 @@ object "EVMInterpreter" {
             function _fetchDeployedCodeLen(addr) -> codeLen {
                 let codeHash := _getRawCodeHash(addr)
             
-                switch shr(248, codeHash)
+                mstore(0, codeHash)
+            
+                let success := staticcall(gas(), CODE_ORACLE_SYSTEM_CONTRACT(), 0, 32, 0, 0)
+            
+                switch iszero(success)
                 case 1 {
-                    // EraVM
-                    let codeLengthInWords := and(shr(224, codeHash), 0xffff)
-                    codeLen := shl(5, codeLengthInWords) // codeLengthInWords * 32
+                    // The code oracle call can only fail in the case where the contract
+                    // we are querying is the current one executing and it has not yet been
+                    // deployed, i.e., if someone calls codesize (or extcodesize(address()))
+                    // inside the constructor. In that case, code length is zero.
+                    codeLen := 0
                 }
-                case 2 {
-                    // EVM
-                    let codeLengthInBytes := and(shr(224, codeHash), 0xffff)
-                    codeLen := codeLengthInBytes
+                default {
+                    // The first word is the true length of the bytecode
+                    returndatacopy(0, 0, 32)
+                    codeLen := mload(0)
                 }
             }
             
@@ -5014,7 +5028,9 @@ object "EVMInterpreter" {
                             evmGasLeft := chargeGas(evmGasLeft, 2500)
                         }
                 
-                        sp := pushStackItemWithoutCheck(sp, _fetchDeployedCodeLen(addr))
+                        switch _isEVM(addr) 
+                            case 0  { sp := pushStackItemWithoutCheck(sp, extcodesize(addr)) }
+                            default { sp := pushStackItemWithoutCheck(sp, _fetchDeployedCodeLen(addr)) }
                         ip := add(ip, 1)
                     }
                     case 0x3C { // OP_EXTCODECOPY
diff --git a/system-contracts/evm-interpreter/EvmInterpreterFunctions.template.yul b/system-contracts/evm-interpreter/EvmInterpreterFunctions.template.yul
index f53c079d8..2e3567f82 100644
--- a/system-contracts/evm-interpreter/EvmInterpreterFunctions.template.yul
+++ b/system-contracts/evm-interpreter/EvmInterpreterFunctions.template.yul
@@ -264,16 +264,22 @@ function _fetchDeployedCodeWithDest(addr, _offset, _len, dest) -> codeLen {
 function _fetchDeployedCodeLen(addr) -> codeLen {
     let codeHash := _getRawCodeHash(addr)
 
-    switch shr(248, codeHash)
+    mstore(0, codeHash)
+
+    let success := staticcall(gas(), CODE_ORACLE_SYSTEM_CONTRACT(), 0, 32, 0, 0)
+
+    switch iszero(success)
     case 1 {
-        // EraVM
-        let codeLengthInWords := and(shr(224, codeHash), 0xffff)
-        codeLen := shl(5, codeLengthInWords) // codeLengthInWords * 32
-    }
-    case 2 {
-        // EVM
-        let codeLengthInBytes := and(shr(224, codeHash), 0xffff)
-        codeLen := codeLengthInBytes
+        // The code oracle call can only fail in the case where the contract
+        // we are querying is the current one executing and it has not yet been
+        // deployed, i.e., if someone calls codesize (or extcodesize(address()))
+        // inside the constructor. In that case, code length is zero.
+        codeLen := 0
+    }
+    default {
+        // The first word is the true length of the bytecode
+        returndatacopy(0, 0, 32)
+        codeLen := mload(0)
     }
 }
 
diff --git a/system-contracts/evm-interpreter/EvmInterpreterLoop.template.yul b/system-contracts/evm-interpreter/EvmInterpreterLoop.template.yul
index 5880cd1f4..dc3346988 100644
--- a/system-contracts/evm-interpreter/EvmInterpreterLoop.template.yul
+++ b/system-contracts/evm-interpreter/EvmInterpreterLoop.template.yul
@@ -480,7 +480,9 @@ for { } true { } {
             evmGasLeft := chargeGas(evmGasLeft, 2500)
         }
 
-        sp := pushStackItemWithoutCheck(sp, _fetchDeployedCodeLen(addr))
+        switch _isEVM(addr) 
+            case 0  { sp := pushStackItemWithoutCheck(sp, extcodesize(addr)) }
+            default { sp := pushStackItemWithoutCheck(sp, _fetchDeployedCodeLen(addr)) }
         ip := add(ip, 1)
     }
     case 0x3C { // OP_EXTCODECOPY