diff --git a/evmcc/evmcc.cpp b/evmcc/evmcc.cpp
index f76b855db..9828d4876 100644
--- a/evmcc/evmcc.cpp
+++ b/evmcc/evmcc.cpp
@@ -171,28 +171,33 @@ int main(int argc, char** argv)
 
 		if (options.count("interpret"))
 		{
-			eth::jit::ExecutionEngine engine;
-			u256 gas = initialGas;
-
-			// Create fake ExtVM interface
-			eth::ExtVMFace ext;
-			ext.myAddress = Address(1122334455667788);
-			ext.caller = Address(0xfacefacefaceface);
-			ext.origin = Address(101010101010101010);
-			ext.value = 0xabcd;
-			ext.gasPrice = 1002;
-			ext.previousBlock.hash = u256(1003);
-			ext.currentBlock.coinbaseAddress = Address(1004);
-			ext.currentBlock.timestamp = 1005;
-			ext.currentBlock.number = 1006;
-			ext.currentBlock.difficulty = 1007;
-			ext.currentBlock.gasLimit = 1008;
-			ext.data = std::string("Hello the Beautiful World of Ethereum!");
-			ext.code = { 0x0d, 0x0e, 0x0a, 0x0d, 0x0b, 0x0e, 0xe, 0xf };
+			using namespace eth::jit;
+
+			ExecutionEngine engine;
+			eth::jit::u256 gas = initialGas;
+
+			// Create random runtime data
+			RuntimeData data;
+			data.set(RuntimeData::Gas, gas);
+			data.set(RuntimeData::Address, (u160)Address(1122334455667788));
+			data.set(RuntimeData::Caller, (u160)Address(0xfacefacefaceface));
+			data.set(RuntimeData::Origin, (u160)Address(101010101010101010));
+			data.set(RuntimeData::CallValue, 0xabcd);
+			data.set(RuntimeData::CallDataSize, 3);
+			data.set(RuntimeData::GasPrice, 1003);
+			data.set(RuntimeData::PrevHash, 1003);
+			data.set(RuntimeData::CoinBase, (u160)Address(101010101010101015));
+			data.set(RuntimeData::TimeStamp, 1005);
+			data.set(RuntimeData::Number, 1006);
+			data.set(RuntimeData::Difficulty, 16);
+			data.set(RuntimeData::GasLimit, 1008);
+			data.set(RuntimeData::CodeSize, bytecode.size());
+			data.callData = (uint8_t*)"abc";
+			data.code = bytecode.data();
 
 			// BROKEN: env_* functions must be implemented & RuntimeData struct created
-			auto result = engine.run(std::move(module), gas, ext);
-			return result;
+			auto result = engine.run(std::move(module), &data, nullptr);
+			return static_cast<int>(result);
 		}
 	}
 
diff --git a/libevmjit-cpp/JitVM.cpp b/libevmjit-cpp/JitVM.cpp
index 104782405..a67678012 100644
--- a/libevmjit-cpp/JitVM.cpp
+++ b/libevmjit-cpp/JitVM.cpp
@@ -13,26 +13,23 @@ bytesConstRef JitVM::go(ExtVMFace& _ext, OnOpFunc const&, uint64_t)
 {
 	using namespace jit;
 
-	RuntimeData data{{},nullptr,nullptr};
-
-#define set(INDEX, VALUE) data.elems[INDEX] = eth2llvm(VALUE)
-	set(RuntimeData::Gas, m_gas);
-	set(RuntimeData::Address, fromAddress(_ext.myAddress));
-	set(RuntimeData::Caller, fromAddress(_ext.caller));
-	set(RuntimeData::Origin, fromAddress(_ext.origin));
-	set(RuntimeData::CallValue, _ext.value);
-	set(RuntimeData::CallDataSize, _ext.data.size());
-	set(RuntimeData::GasPrice, _ext.gasPrice);
-	set(RuntimeData::PrevHash, _ext.previousBlock.hash);
-	set(RuntimeData::CoinBase, fromAddress(_ext.currentBlock.coinbaseAddress));
-	set(RuntimeData::TimeStamp, _ext.currentBlock.timestamp);
-	set(RuntimeData::Number, _ext.currentBlock.number);
-	set(RuntimeData::Difficulty, _ext.currentBlock.difficulty);
-	set(RuntimeData::GasLimit, _ext.currentBlock.gasLimit);
-	set(RuntimeData::CodeSize, _ext.code.size());   // TODO: Use constant
+	RuntimeData data;
+	data.set(RuntimeData::Gas, m_gas);
+	data.set(RuntimeData::Address, fromAddress(_ext.myAddress));
+	data.set(RuntimeData::Caller, fromAddress(_ext.caller));
+	data.set(RuntimeData::Origin, fromAddress(_ext.origin));
+	data.set(RuntimeData::CallValue, _ext.value);
+	data.set(RuntimeData::CallDataSize, _ext.data.size());
+	data.set(RuntimeData::GasPrice, _ext.gasPrice);
+	data.set(RuntimeData::PrevHash, _ext.previousBlock.hash);
+	data.set(RuntimeData::CoinBase, fromAddress(_ext.currentBlock.coinbaseAddress));
+	data.set(RuntimeData::TimeStamp, _ext.currentBlock.timestamp);
+	data.set(RuntimeData::Number, _ext.currentBlock.number);
+	data.set(RuntimeData::Difficulty, _ext.currentBlock.difficulty);
+	data.set(RuntimeData::GasLimit, _ext.currentBlock.gasLimit);
+	data.set(RuntimeData::CodeSize, _ext.code.size());
 	data.callData = _ext.data.data();
 	data.code = _ext.code.data();
-#undef set
 
 	ExecutionEngine engine;
 	auto env = reinterpret_cast<Env*>(&_ext);
@@ -62,7 +59,7 @@ bytesConstRef JitVM::go(ExtVMFace& _ext, OnOpFunc const&, uint64_t)
 
 namespace
 {
-	// MSVS linker ignores export symbols in Env.cpp if nothing point at least one of them
+	// MSVS linker ignores export symbols in Env.cpp if nothing points at least one of them
 	extern "C" void env_sload();
 	void linkerWorkaround() 
 	{ 
diff --git a/libevmjit/RuntimeData.h b/libevmjit/RuntimeData.h
index fc372fee3..b17f52620 100644
--- a/libevmjit/RuntimeData.h
+++ b/libevmjit/RuntimeData.h
@@ -1,6 +1,6 @@
 #pragma once
 
-#include "Common.h"
+#include "Utils.h"
 
 
 namespace dev
@@ -35,9 +35,11 @@ struct RuntimeData
 		ReturnDataSize = CallDataSize
 	};
 
-	i256 elems[_size];
-	byte const* callData;
-	byte const* code;
+	i256 elems[_size] = {};
+	byte const* callData = nullptr;
+	byte const* code = nullptr;
+
+	void set(Index _index, u256 _value) { elems[_index] = eth2llvm(_value); }
 };
 
 /// VM Environment (ExtVM) opaque type