diff --git a/evmcc/Compiler.cpp b/evmcc/Compiler.cpp
index ab16c50f1..00f2fb00b 100644
--- a/evmcc/Compiler.cpp
+++ b/evmcc/Compiler.cpp
@@ -247,6 +247,22 @@ std::unique_ptr<llvm::Module> Compiler::compile(const dev::bytes& bytecode)
 			break;
 		}
 
+		case Instruction::SLOAD:
+		{
+			auto index = stack.pop();
+			auto value = ext.store(index);
+			stack.push(value);
+			break;
+		}
+
+		case Instruction::SSTORE:
+		{
+			auto index = stack.pop();
+			auto value = stack.pop();
+			ext.setStore(index, value);
+			break;
+		}
+
 		}
 	}
 
diff --git a/evmcc/Ext.cpp b/evmcc/Ext.cpp
index 1384694be..35606f67f 100644
--- a/evmcc/Ext.cpp
+++ b/evmcc/Ext.cpp
@@ -4,6 +4,8 @@
 #include <llvm/IR/Function.h>
 #include <llvm/IR/TypeBuilder.h>
 
+#include "Utils.h"
+
 #ifdef _MSC_VER
 #define EXPORT __declspec(dllexport)
 #else
@@ -30,21 +32,42 @@ Ext::Ext(llvm::IRBuilder<>& _builder)
 	auto module = m_builder.GetInsertBlock()->getParent()->getParent();
 	auto&& ctx = _builder.getContext();
 
-	Function::Create(TypeBuilder<void(i<256>*, i<256>*), true>::get(ctx), Linkage::ExternalLinkage, "ext_store", module);
-	Function::Create(TypeBuilder<void(i<256>*, i<256>*), true>::get(ctx), Linkage::ExternalLinkage, "ext_setStore", module);
+	m_args[0] = m_builder.CreateAlloca(m_builder.getIntNTy(256), nullptr, "ext.index");
+	m_args[1] = m_builder.CreateAlloca(m_builder.getIntNTy(256), nullptr, "ext.value");
+
+	m_store    = Function::Create(TypeBuilder<void(i<256>*, i<256>*), true>::get(ctx), Linkage::ExternalLinkage, "ext_store", module);
+	m_setStore = Function::Create(TypeBuilder<void(i<256>*, i<256>*), true>::get(ctx), Linkage::ExternalLinkage, "ext_setStore", module);
 }
 
-extern "C"
+llvm::Value* Ext::store(llvm::Value* _index)
 {
+	m_builder.CreateStore(_index, m_args[0]);
+	m_builder.CreateCall(m_store, m_args);
+	return m_builder.CreateLoad(m_args[1]);
+}
 
-EXPORT void ext_store(void* _index, void* _value)
+void Ext::setStore(llvm::Value* _index, llvm::Value* _value)
 {
-
+	m_builder.CreateStore(_index, m_args[0]);
+	m_builder.CreateStore(_value, m_args[1]);
+	m_builder.CreateCall(m_setStore, m_args);
 }
 
-EXPORT void ext_setStore(void* _index, void* _value)
+extern "C"
 {
 
+EXPORT void ext_store(i256* _index, i256* _value)
+{
+	auto index = llvm2eth(*_index);
+	auto value = g_ext->store(index);
+	*_value = eth2llvm(value);
+}
+
+EXPORT void ext_setStore(i256* _index, i256* _value)
+{
+	auto index = llvm2eth(*_index);
+	auto value = llvm2eth(*_value);
+	g_ext->setStore(index, value);
 }
 
 }
diff --git a/evmcc/Ext.h b/evmcc/Ext.h
index f1c88d849..4de1c6645 100644
--- a/evmcc/Ext.h
+++ b/evmcc/Ext.h
@@ -1,4 +1,6 @@
 
+#pragma once
+
 #include <llvm/IR/IRBuilder.h>
 
 #include <libevm/ExtVMFace.h>
@@ -14,8 +16,15 @@ public:
 	Ext(llvm::IRBuilder<>& _builder);
 	static void init(std::unique_ptr<dev::eth::ExtVMFace> _ext);
 
+	llvm::Value* store(llvm::Value* _index);
+	void setStore(llvm::Value* _index, llvm::Value* _value);
+
 private:
 	llvm::IRBuilder<>& m_builder;
+
+	llvm::Value* m_args[2];
+	llvm::Function* m_store;
+	llvm::Function* m_setStore;
 };
 	
 
diff --git a/evmcc/Stack.cpp b/evmcc/Stack.cpp
index aa02a846e..877b192d9 100644
--- a/evmcc/Stack.cpp
+++ b/evmcc/Stack.cpp
@@ -9,6 +9,8 @@
 
 #include <llvm/IR/Function.h>
 
+#include "Utils.h"
+
 #ifdef _MSC_VER
 	#define EXPORT __declspec(dllexport)
 #else
@@ -18,15 +20,6 @@
 namespace evmcc
 {
 
-struct i256
-{
-	uint64_t a;
-	uint64_t b;
-	uint64_t c;
-	uint64_t d;
-};
-static_assert(sizeof(i256) == 32, "Wrong i265 size");
-
 using StackImpl = std::vector<i256>;
 
 
diff --git a/evmcc/Utils.cpp b/evmcc/Utils.cpp
new file mode 100644
index 000000000..cef08a283
--- /dev/null
+++ b/evmcc/Utils.cpp
@@ -0,0 +1,34 @@
+
+#include "Utils.h"
+
+namespace evmcc
+{
+
+dev::u256 llvm2eth(i256 _i)
+{
+	dev::u256 u = 0;
+	u |= _i.d;
+	u <<= 64;
+	u |= _i.c;
+	u <<= 64;
+	u |= _i.b;
+	u <<= 64;
+	u |= _i.a;
+	return u;
+}
+
+i256 eth2llvm(dev::u256 _u)
+{
+	i256 i;
+	dev::u256 mask = 0xFFFFFFFFFFFFFFFF;
+	i.a = static_cast<uint64_t>(_u & mask);
+	_u >>= 64;
+	i.b = static_cast<uint64_t>(_u & mask);
+	_u >>= 64;
+	i.c = static_cast<uint64_t>(_u & mask);
+	_u >>= 64;
+	i.d = static_cast<uint64_t>(_u & mask);
+	return i;
+}
+
+}
\ No newline at end of file
diff --git a/evmcc/Utils.h b/evmcc/Utils.h
new file mode 100644
index 000000000..065698448
--- /dev/null
+++ b/evmcc/Utils.h
@@ -0,0 +1,24 @@
+
+#pragma once
+
+#include <cstdint>
+
+#include <libdevcore/Common.h>
+
+namespace evmcc
+{
+
+/// Representation of 256-bit value binary compatible with LLVM i256
+struct i256
+{
+	uint64_t a;
+	uint64_t b;
+	uint64_t c;
+	uint64_t d;
+};
+static_assert(sizeof(i256) == 32, "Wrong i265 size");
+
+dev::u256 llvm2eth(i256);
+i256 eth2llvm(dev::u256);
+
+}
\ No newline at end of file
diff --git a/evmcc/bytecode/store_test.evm b/evmcc/bytecode/store_test.evm
new file mode 100644
index 000000000..54c9419b5
--- /dev/null
+++ b/evmcc/bytecode/store_test.evm
@@ -0,0 +1 @@
+607b607c60015760005760015660005603
diff --git a/evmcc/lll/stack_test.lll b/evmcc/lll/stack_test.lll
index e6581563c..fdf83594c 100644
--- a/evmcc/lll/stack_test.lll
+++ b/evmcc/lll/stack_test.lll
@@ -1,24 +1,8 @@
 
 (asm 
-60666666666606
-7077777777777707
-DUP1
-DUP3
-DUP1
-DUP5
-DUP2
-DUP5
-POP
-POP
-POP
-POP
-POP
-POP
-POP
-1111
-2222
-DUP2
-DUP2
-SWAP3
-SWAP1
+123
+SSTORE
+SLOAD
+123
+SUB
 )
\ No newline at end of file
diff --git a/evmcc/lll/store_test.lll b/evmcc/lll/store_test.lll
new file mode 100644
index 000000000..c40471c40
--- /dev/null
+++ b/evmcc/lll/store_test.lll
@@ -0,0 +1,14 @@
+
+(asm 
+123
+124
+1
+SSTORE
+0
+SSTORE
+1
+SLOAD
+0
+SLOAD
+SUB
+)
\ No newline at end of file
diff --git a/windows/evmcc.vcxproj b/windows/evmcc.vcxproj
index d10235ee3..7959c5a1b 100644
--- a/windows/evmcc.vcxproj
+++ b/windows/evmcc.vcxproj
@@ -23,13 +23,17 @@
     <ClCompile Include="..\evmcc\evmcc.cpp" />
     <ClCompile Include="..\evmcc\ExecutionEngine.cpp" />
     <ClCompile Include="..\evmcc\Ext.cpp" />
+    <ClCompile Include="..\evmcc\Memory.cpp" />
     <ClCompile Include="..\evmcc\Stack.cpp" />
+    <ClCompile Include="..\evmcc\Utils.cpp" />
   </ItemGroup>
   <ItemGroup>
     <ClInclude Include="..\evmcc\Compiler.h" />
     <ClInclude Include="..\evmcc\ExecutionEngine.h" />
     <ClInclude Include="..\evmcc\Ext.h" />
+    <ClInclude Include="..\evmcc\Memory.h" />
     <ClInclude Include="..\evmcc\Stack.h" />
+    <ClInclude Include="..\evmcc\Utils.h" />
   </ItemGroup>
   <PropertyGroup Label="Globals">
     <ProjectGuid>{D51A4898-BD9E-4961-BCAE-1FE7F854BB4D}</ProjectGuid>
diff --git a/windows/evmcc.vcxproj.filters b/windows/evmcc.vcxproj.filters
index 7b0ee824a..99c43b89b 100644
--- a/windows/evmcc.vcxproj.filters
+++ b/windows/evmcc.vcxproj.filters
@@ -6,11 +6,15 @@
     <ClCompile Include="..\evmcc\ExecutionEngine.cpp" />
     <ClCompile Include="..\evmcc\Stack.cpp" />
     <ClCompile Include="..\evmcc\Ext.cpp" />
+    <ClCompile Include="..\evmcc\Memory.cpp" />
+    <ClCompile Include="..\evmcc\Utils.cpp" />
   </ItemGroup>
   <ItemGroup>
     <ClInclude Include="..\evmcc\Compiler.h" />
     <ClInclude Include="..\evmcc\ExecutionEngine.h" />
     <ClInclude Include="..\evmcc\Stack.h" />
     <ClInclude Include="..\evmcc\Ext.h" />
+    <ClInclude Include="..\evmcc\Memory.h" />
+    <ClInclude Include="..\evmcc\Utils.h" />
   </ItemGroup>
 </Project>
\ No newline at end of file