diff --git a/libevmjit-cpp/Env.cpp b/libevmjit-cpp/Env.cpp
index e9439f1ae..b0f95f453 100644
--- a/libevmjit-cpp/Env.cpp
+++ b/libevmjit-cpp/Env.cpp
@@ -36,6 +36,7 @@ extern "C"
 		_env->setStore(index, value);	// Interface uses native endianness
 	}
 
+	// TODO: Move to Memory/Runtime
 	EXPORT void ext_calldataload(ExtVMFace* _env, i256* _index, ::byte* o_value)
 	{
 		auto index = static_cast<size_t>(llvm2eth(*_index));
@@ -72,32 +73,24 @@ extern "C"
 			*o_address = {};
 	}
 
-	EXPORT void ext_call(ExtVMFace* _env, i256* io_gas, h256* _receiveAddress, i256* _value, i256* _inOff, i256* _inSize, i256* _outOff, i256* _outSize, h256* _codeAddress, i256* o_ret)
+	EXPORT bool env_call(ExtVMFace* _env, i256* io_gas, h256* _receiveAddress, i256* _value, byte* _inBeg, uint64_t _inSize, byte* _outBeg, uint64_t _outSize, h256* _codeAddress)
 	{
-		auto&& ext = *_env;
 		auto value = llvm2eth(*_value);
-
-		auto ret = false;
-		auto gas = llvm2eth(*io_gas);
-		if (ext.balance(ext.myAddress) >= value)
+		if (_env->balance(_env->myAddress) >= value)
 		{
-			ext.subBalance(value);
+			_env->subBalance(value);
 			auto receiveAddress = right160(*_receiveAddress);
-			auto inOff = static_cast<size_t>(llvm2eth(*_inOff));
-			auto inSize = static_cast<size_t>(llvm2eth(*_inSize));
-			auto outOff = static_cast<size_t>(llvm2eth(*_outOff));
-			auto outSize = static_cast<size_t>(llvm2eth(*_outSize));
-			//auto&& inRef = bytesConstRef(_rt->getMemory().data() + inOff, inSize);
-			//auto&& outRef = bytesConstRef(_rt->getMemory().data() + outOff, outSize);
-			auto inRef = bytesConstRef(); // FIXME: Handle memory
-			auto outRef = bytesConstRef(); // FIXME: Handle memory
+			auto inRef = bytesConstRef{_inBeg, _inSize};
+			auto outRef = bytesConstRef{_outBeg, _outSize};
 			OnOpFunc onOp {}; // TODO: Handle that thing
 			auto codeAddress = right160(*_codeAddress);
-			ret = ext.call(receiveAddress, value, inRef, &gas, outRef, onOp, {}, codeAddress);
+			auto gas = llvm2eth(*io_gas);
+			auto ret = _env->call(receiveAddress, value, inRef, &gas, outRef, onOp, {}, codeAddress);
+			*io_gas = eth2llvm(gas);
+			return ret;
 		}
 
-		*io_gas = eth2llvm(gas);
-		o_ret->a = ret ? 1 : 0;
+		return false;
 	}
 
 	EXPORT void env_sha3(byte* _begin, uint64_t _size, h256* o_hash)
diff --git a/libevmjit/Ext.cpp b/libevmjit/Ext.cpp
index c870bdf6a..51e0b5ded 100644
--- a/libevmjit/Ext.cpp
+++ b/libevmjit/Ext.cpp
@@ -48,7 +48,6 @@ Ext::Ext(RuntimeManager& _runtimeManager, Memory& _memoryMan):
 	m_calldataload = llvm::Function::Create(llvm::FunctionType::get(Type::Void, {argsTypes, 3}, false), Linkage::ExternalLinkage, "ext_calldataload", module);
 	m_balance = llvm::Function::Create(llvm::FunctionType::get(Type::Void, {argsTypes, 3}, false), Linkage::ExternalLinkage, "ext_balance", module);
 	m_suicide = llvm::Function::Create(llvm::FunctionType::get(Type::Void, {argsTypes, 2}, false), Linkage::ExternalLinkage, "ext_suicide", module);
-	m_call = llvm::Function::Create(llvm::FunctionType::get(Type::Void, argsTypes, false), Linkage::ExternalLinkage, "ext_call", module);
 	m_exp = llvm::Function::Create(llvm::FunctionType::get(Type::Void, {argsTypes, 4}, false), Linkage::ExternalLinkage, "ext_exp", module);
 	m_codeAt = llvm::Function::Create(llvm::FunctionType::get(Type::BytePtr, {argsTypes, 2}, false), Linkage::ExternalLinkage, "ext_codeAt", module);
 	m_codesizeAt = llvm::Function::Create(llvm::FunctionType::get(Type::Void, {argsTypes, 3}, false), Linkage::ExternalLinkage, "ext_codesizeAt", module);
@@ -63,6 +62,9 @@ Ext::Ext(RuntimeManager& _runtimeManager, Memory& _memoryMan):
 
 	llvm::Type* createArgsTypes[] = {Type::EnvPtr, Type::WordPtr, Type::BytePtr, Type::Size, Type::WordPtr};
 	m_create = llvm::Function::Create(llvm::FunctionType::get(Type::Void, createArgsTypes, false), Linkage::ExternalLinkage, "env_create", module);
+
+	llvm::Type* callArgsTypes[] = {Type::EnvPtr, Type::WordPtr, Type::WordPtr, Type::WordPtr, Type::BytePtr, Type::Size, Type::BytePtr, Type::Size, Type::WordPtr};
+	m_call = llvm::Function::Create(llvm::FunctionType::get(Type::Bool, callArgsTypes, false), Linkage::ExternalLinkage, "env_call", module);
 }
 
 llvm::Value* Ext::sload(llvm::Value* _index)
@@ -119,15 +121,15 @@ llvm::Value* Ext::call(llvm::Value*& _gas, llvm::Value* _receiveAddress, llvm::V
 	auto receiveAddress = Endianness::toBE(m_builder, _receiveAddress);
 	m_builder.CreateStore(receiveAddress, m_arg2);
 	m_builder.CreateStore(_value, m_arg3);
-	m_builder.CreateStore(_inOff, m_arg4);
-	m_builder.CreateStore(_inSize, m_arg5);
-	m_builder.CreateStore(_outOff, m_arg6);
-	m_builder.CreateStore(_outSize, m_arg7);
+	auto inBeg = m_memoryMan.getBytePtr(_inOff);
+	auto inSize = m_builder.CreateTrunc(_inSize, Type::Size, "in.size");
+	auto outBeg = m_memoryMan.getBytePtr(_outOff);
+	auto outSize = m_builder.CreateTrunc(_outSize, Type::Size, "out.size");
 	auto codeAddress = Endianness::toBE(m_builder, _codeAddress);
 	m_builder.CreateStore(codeAddress, m_arg8);
-	createCall(m_call, getRuntimeManager().getEnv(), m_args[0], m_arg2, m_arg3, m_arg4, m_arg5, m_arg6, m_arg7, m_arg8, m_args[1]);
+	auto ret = createCall(m_call, getRuntimeManager().getEnv(), m_args[0], m_arg2, m_arg3, inBeg, inSize, outBeg, outSize, m_arg8);
 	_gas = m_builder.CreateLoad(m_args[0]); // Return gas
-	return m_builder.CreateLoad(m_args[1]);
+	return m_builder.CreateZExt(ret, Type::Word, "ret");
 }
 
 llvm::Value* Ext::sha3(llvm::Value* _inOff, llvm::Value* _inSize)
diff --git a/libevmjit/Type.cpp b/libevmjit/Type.cpp
index 62b819dc8..dcff24153 100644
--- a/libevmjit/Type.cpp
+++ b/libevmjit/Type.cpp
@@ -15,6 +15,7 @@ namespace jit
 llvm::IntegerType* Type::Word;
 llvm::PointerType* Type::WordPtr;
 llvm::IntegerType* Type::lowPrecision;
+llvm::IntegerType* Type::Bool;
 llvm::IntegerType* Type::Size;
 llvm::IntegerType* Type::Byte;
 llvm::PointerType* Type::BytePtr;
@@ -32,6 +33,7 @@ void Type::init(llvm::LLVMContext& _context)
 		WordPtr = Word->getPointerTo();
 		lowPrecision = llvm::Type::getInt64Ty(_context);
 		// TODO: Size should be architecture-dependent
+		Bool = llvm::Type::getInt1Ty(_context);
 		Size = llvm::Type::getInt64Ty(_context);
 		Byte = llvm::Type::getInt8Ty(_context);
 		BytePtr = Byte->getPointerTo();
diff --git a/libevmjit/Type.h b/libevmjit/Type.h
index b0e3fa237..fd3c905d1 100644
--- a/libevmjit/Type.h
+++ b/libevmjit/Type.h
@@ -21,6 +21,7 @@ struct Type
 	/// @TODO: Use 64-bit for now. In 128-bit compiler-rt library functions are required
 	static llvm::IntegerType* lowPrecision;
 
+	static llvm::IntegerType* Bool;
 	static llvm::IntegerType* Size;
 
 	static llvm::IntegerType* Byte;