diff --git a/CMakeLists.txt b/CMakeLists.txt
index 2750cbe..f605b64 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -40,6 +40,7 @@ endif()
 option( UNITY_BUILD OFF )
 
 FIND_PACKAGE( OpenSSL )
+#FIND_PACKAGE( ZLIB )
 
 include_directories( vendor/zlib-1.2.7/)
 include_directories( vendor/libssh2-1.4.2/include )
@@ -98,7 +99,7 @@ add_subdirectory(vendor)
 
 setup_library( fc SOURCES ${sources} )
 
-#setup_executable( json_rpc_test SOURCES tests/json_rpc_test.cpp LIBRARIES fc ${pthread_library} ${rt_library} ${Boost_THREAD_LIBRARY} ${Boost_CONTEXT_LIBRARY} ${Boost_SYSTEM_LIBRARY} ${Boost_CHRONO_LIBRARY} ${Boost_FILESYSTEM_LIBRARY} ${rt_library}  ${Boost_DATE_TIME_LIBRARY})
+#setup_executable( json_rpc_test SOURCES tests/json_rpc_test.cpp LIBRARIES fc ${ZLIB_LIBRARY} ${pthread_library} ${rt_library} ${Boost_THREAD_LIBRARY} ${Boost_CONTEXT_LIBRARY} ${Boost_SYSTEM_LIBRARY} ${Boost_CHRONO_LIBRARY} ${Boost_FILESYSTEM_LIBRARY} ${rt_library}  ${Boost_DATE_TIME_LIBRARY})
 #setup_executable( ssh_test SOURCES tests/ssh.cpp LIBRARIES fc ${pthread_library} ${rt_library} ${Boost_THREAD_LIBRARY} ${Boost_CONTEXT_LIBRARY} ${Boost_SYSTEM_LIBRARY} ${Boost_CHRONO_LIBRARY} ${Boost_FILESYSTEM_LIBRARY} ${rt_library} ssh2 ${OPENSSL_LIBRARY} ${OPENSSL_CRYPTO_LIBRARY} ${ZLIB_LIBRARY} ${ALL_OPENSSL_LIBRARIES} ${Boost_DATE_TIME_LIBRARY})
 
 #add_executable( test_vec tests/vector_test.cpp )
diff --git a/include/fc/interprocess/file_mapping.hpp b/include/fc/interprocess/file_mapping.hpp
index 8f01ab7..0610887 100644
--- a/include/fc/interprocess/file_mapping.hpp
+++ b/include/fc/interprocess/file_mapping.hpp
@@ -1,5 +1,4 @@
-#ifndef _FC_INTERPROCESS_FILEMAPPING_HPP_
-#define _FC_INTERPROCESS_FILEMAPPING_HPP_
+#pragma once
 #include <fc/fwd.hpp>
 #include <fc/utility.hpp>
 
@@ -35,4 +34,3 @@ namespace fc {
       fc::fwd<boost::interprocess::mapped_region,40> my;
   };
 }
-#endif
diff --git a/include/fc/signal.hpp b/include/fc/signal.hpp
new file mode 100644
index 0000000..925ef4f
--- /dev/null
+++ b/include/fc/signal.hpp
@@ -0,0 +1,48 @@
+#pragma once
+#include <fc/vector.hpp>
+#include <functional>
+
+
+namespace fc {
+  
+  template<typename Signature>
+  class signal  {
+    public:
+      typedef int64_t connection_id_type;
+
+      template<typename Functor>
+      connection_id_type connect( Functor&& f ) {
+         auto c = new std::function<Signature>( fc::forward<Functor>(f) ); 
+         _handlers.push_back( c );
+         return reinterpret_cast<connection_id_type>(c);
+      }
+
+      template<typename... Args>
+      void emit( Args&&... args ) {
+        for( size_t i = 0; i < _handlers.size(); ++i ) {
+          (*_handlers[i])( args... );
+        }
+      }
+      template<typename... Args>
+      void operator()( Args&&... args ) {
+        for( size_t i = 0; i < _handlers.size(); ++i ) {
+          (*_handlers[i])( args... );
+        }
+      }
+
+      void disconnect( connection_id_type cid ) {
+        auto itr = _handlers.begin();
+        while( itr != _handlers.end() ) {
+          if( reinterpret_cast<connection_id_type>(*itr) == cid ) {
+            delete *itr;
+            _handlers.erase(itr);
+          }
+          ++itr;
+        }
+      }
+
+    private:
+      fc::vector< std::function<Signature>* > _handlers;
+  };
+
+}
diff --git a/include/fc/signals.hpp b/include/fc/signals.hpp
index 105fdc4..97e3518 100644
--- a/include/fc/signals.hpp
+++ b/include/fc/signals.hpp
@@ -1,5 +1,3 @@
-#ifndef _FC_SIGNALS_HPP
-#define _FC_SIGNALS_HPP
 #include <boost/signal.hpp>
 #include <fc/future.hpp>
 #include <fc/thread.hpp>
@@ -27,4 +25,3 @@ namespace fc {
    }
 } 
 
-#endif
diff --git a/include/fc/spin_lock.hpp b/include/fc/spin_lock.hpp
index 489e9e6..6dfbd1a 100644
--- a/include/fc/spin_lock.hpp
+++ b/include/fc/spin_lock.hpp
@@ -1,6 +1,3 @@
-#ifndef _FC_SPIN_LOCK_HPP_
-#define _FC_SPIN_LOCK_HPP_
-
 namespace boost {
   template<typename T> class atomic;
 }
@@ -38,4 +35,3 @@ namespace fc {
 
 } // namespace fc
 
-#endif // _FC_SPIN_LOCK_HPP_
diff --git a/src/lexical_cast.cpp b/src/lexical_cast.cpp
index 7a8ba3a..142e200 100644
--- a/src/lexical_cast.cpp
+++ b/src/lexical_cast.cpp
@@ -13,6 +13,9 @@ namespace fc {
       return boost::lexical_cast<uint64_t>(s.c_str());
     }
     fc::string to_string( double d   ){ return boost::lexical_cast<std::string>(d); }
+    #ifdef __APPLE__
+    fc::string to_string( size_t d   ){ return boost::lexical_cast<std::string>(d); }
+    #endif
     fc::string to_string( uint64_t d ){ return boost::lexical_cast<std::string>(d); }
     fc::string to_string( uint32_t d  ){ return boost::lexical_cast<std::string>(d); }
     fc::string to_string( uint16_t d  ){ return boost::lexical_cast<std::string>(d); }
diff --git a/vendor/CMakeLists.txt b/vendor/CMakeLists.txt
index b565b83..7b4140e 100644
--- a/vendor/CMakeLists.txt
+++ b/vendor/CMakeLists.txt
@@ -1,3 +1,3 @@
 add_subdirectory( libssh2-1.4.2 )
 add_subdirectory( zlib-1.2.7)
-add_subdirectory( sigar )
+#add_subdirectory( sigar )