diff --git a/CMakeLists.txt b/CMakeLists.txt
index e269e91..d56f86d 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -2,7 +2,7 @@ PROJECT( fc )
 
 CMAKE_MINIMUM_REQUIRED( VERSION 2.8.0 )
 
-SET( CMAKE_MODULE_PATH "${CMAKE_SOURCE_DIR}/CMakeModules;${CMAKE_MODULE_PATH}" )
+SET( CMAKE_MODULE_PATH "${CMAKE_CURRENT_SOURCE_DIR}/CMakeModules;${CMAKE_MODULE_PATH}" )
 
 INCLUDE( VersionMacros )
 INCLUDE( SetupTargetMacros )
@@ -40,7 +40,7 @@ endif()
 option( UNITY_BUILD OFF )
 
 FIND_PACKAGE( OpenSSL )
-#FIND_PACKAGE( ZLIB )
+FIND_PACKAGE( ZLIB )
 
 include_directories( vendor/zlib-1.2.7/)
 include_directories( vendor/libssh2-1.4.2/include )
@@ -83,6 +83,7 @@ set( sources
   src/thread.cpp
   src/hex.cpp
   src/sha1.cpp
+  src/sha256.cpp
   src/filesystem.cpp
   src/ip.cpp
   src/bigint.cpp
diff --git a/include/fc/sha256.hpp b/include/fc/sha256.hpp
new file mode 100644
index 0000000..1b04db5
--- /dev/null
+++ b/include/fc/sha256.hpp
@@ -0,0 +1,69 @@
+#pragma once
+#include <fc/fwd.hpp>
+#include <fc/string.hpp>
+#include <fc/reflect.hpp>
+
+namespace fc {
+  class path;
+
+  class sha256 {
+    public:
+      sha256();
+      explicit sha256( const fc::string& hex_str );
+
+      fc::string str()const;
+
+      operator fc::string()const;
+
+      char*    data()const;
+
+      static sha256 hash( const char* d, uint32_t dlen );
+      static sha256 hash( const fc::string& );
+      static sha256 hash( const fc::path& );
+
+      template<typename T>
+      static sha256 hash( const T& t ) { sha256::encoder e; e << t; return e.result(); } 
+
+      class encoder {
+        public:
+          encoder();
+          ~encoder();
+
+          void write( const char* d, uint32_t dlen );
+          void put( char c ) { write( &c, 1 ); }
+          void reset();
+          sha256 result();
+
+        private:
+          struct      impl;
+          fwd<impl,96> my;
+      };
+
+      template<typename T>
+      inline friend T& operator<<( T& ds, const sha256& ep ) {
+        ds.write( ep.data(), sizeof(ep) );
+        return ds;
+      }
+
+      template<typename T>
+      inline friend T& operator>>( T& ds, sha256& ep ) {
+        ds.read( ep.data(), sizeof(ep) );
+        return ds;
+      }
+      friend sha256 operator << ( const sha256& h1, uint32_t i );
+      friend bool operator == ( const sha256& h1, const sha256& h2 );
+      friend bool operator != ( const sha256& h1, const sha256& h2 );
+      friend sha256 operator ^ ( const sha256& h1, const sha256& h2 );
+      friend bool operator >= ( const sha256& h1, const sha256& h2 );
+      friend bool operator > ( const sha256& h1, const sha256& h2 ); 
+      friend bool operator < ( const sha256& h1, const sha256& h2 ); 
+
+      uint64_t _hash[4]; 
+  };
+
+  class value;
+  void pack( fc::value& , const fc::sha256&  );
+  void unpack( const fc::value& , fc::sha256&  );
+}
+
+
diff --git a/src/sha256.cpp b/src/sha256.cpp
new file mode 100644
index 0000000..7473839
--- /dev/null
+++ b/src/sha256.cpp
@@ -0,0 +1,105 @@
+#include <fc/hex.hpp>
+#include <fc/sha256.hpp>
+#include <fc/fwd_impl.hpp>
+#include <openssl/sha.h>
+#include <string.h>
+#include <fc/filesystem.hpp>
+#include <fc/interprocess/file_mapping.hpp>
+#include <fc/value.hpp>
+#include <fc/value_cast.hpp>
+
+namespace fc {
+  
+  sha256::sha256() { memset( _hash, 0, sizeof(_hash) ); }
+  sha256::sha256( const fc::string& hex_str ) {
+    fc::from_hex( hex_str, (char*)_hash, sizeof(_hash) );  
+  }
+
+  fc::string sha256::str()const {
+    return to_hex( (char*)_hash, sizeof(_hash) );
+  }
+  sha256::operator fc::string()const { return  str(); }
+
+  char* sha256::data()const { return (char*)&_hash[0]; }
+
+
+  struct sha256::encoder::impl {
+     SHA_CTX ctx;
+  };
+
+  sha256::encoder::~encoder() {}
+  sha256::encoder::encoder() {
+    reset();
+  }
+
+  sha256 sha256::hash( const char* d, uint32_t dlen ) {
+    encoder e;
+    e.write(d,dlen);
+    return e.result();
+  }
+  sha256 sha256::hash( const fc::string& s ) {
+    return hash( s.c_str(), s.size() );
+  }
+  sha256 sha256::hash( const fc::path& s ) {
+    file_mapping fmap( s.string().c_str(), read_only );
+    size_t       fsize = file_size(s);
+    mapped_region mr( fmap, fc::read_only, 0, fsize );
+
+    const char* pos = reinterpret_cast<const char*>(mr.get_address());
+    return hash( pos, fsize );
+  }
+
+  void sha256::encoder::write( const char* d, uint32_t dlen ) {
+    SHA1_Update( &my->ctx, d, dlen); 
+  }
+  sha256 sha256::encoder::result() {
+    sha256 h;
+    SHA1_Final((uint8_t*)h.data(), &my->ctx );
+    return h;
+  }
+  void sha256::encoder::reset() {
+    SHA1_Init( &my->ctx);  
+  }
+
+  fc::sha256 operator << ( const fc::sha256& h1, uint32_t i ) {
+    fc::sha256 result;
+    uint8_t* r = (uint8_t*)result._hash;
+    uint8_t* s = (uint8_t*)h1._hash;
+    for( uint32_t p = 0; p < sizeof(h1._hash)-1; ++p )
+        r[p] = s[p] << i | (s[p+1]>>(8-i));
+    r[31] = s[31] << i;
+    return result;
+  }
+  fc::sha256 operator ^ ( const fc::sha256& h1, const fc::sha256& h2 ) {
+    fc::sha256 result;
+    result._hash[0] = h1._hash[0] ^ h2._hash[0];
+    result._hash[1] = h1._hash[1] ^ h2._hash[1];
+    result._hash[2] = h1._hash[2] ^ h2._hash[2];
+    result._hash[3] = h1._hash[3] ^ h2._hash[3];
+    return result;
+  }
+  bool operator >= ( const fc::sha256& h1, const fc::sha256& h2 ) {
+    return memcmp( h1._hash, h2._hash, sizeof(h1._hash) ) >= 0;
+  }
+  bool operator > ( const fc::sha256& h1, const fc::sha256& h2 ) {
+    return memcmp( h1._hash, h2._hash, sizeof(h1._hash) ) > 0;
+  }
+  bool operator < ( const fc::sha256& h1, const fc::sha256& h2 ) {
+    return memcmp( h1._hash, h2._hash, sizeof(h1._hash) ) < 0;
+  }
+  bool operator != ( const fc::sha256& h1, const fc::sha256& h2 ) {
+    return memcmp( h1._hash, h2._hash, sizeof(h1._hash) ) != 0;
+  }
+  bool operator == ( const fc::sha256& h1, const fc::sha256& h2 ) {
+    return memcmp( h1._hash, h2._hash, sizeof(h1._hash) ) == 0;
+  }
+
+  void pack( fc::value& v, const fc::sha256& s ) {
+      v = fc::string(s);
+  }
+  void unpack( const fc::value& v, fc::sha256& s ) {
+      s = sha256(fc::value_cast<fc::string>(v));
+  }
+  
+} // namespace fc
+