diff --git a/server/Makefile b/server/Makefile
index 3fc5032..3b404c8 100644
--- a/server/Makefile
+++ b/server/Makefile
@@ -1,7 +1,7 @@
 BUILD_ON=$(shell uname)
 BUILD_FOR=$(BUILD_ON)
 
-CXX = c++ -std=c++11 -Wall -O0 -g -fstack-protector-all
+CXX = c++ -std=c++11 -Wall -O3 -g -fstack-protector-all
 
 ifeq ($(BUILD_ON),Darwin)
 ifeq ($(BUILD_FOR),Darwin)
diff --git a/server/json_rpc.hh b/server/json_rpc.hh
index 4654280..d178f77 100644
--- a/server/json_rpc.hh
+++ b/server/json_rpc.hh
@@ -24,7 +24,7 @@ enum class JSON_RPC
 js::Object call(const FunctionMap& fm, const js::Object& request, Context* context);
 
 // create a JSON-RPC 2.0 compatible result response object
-js::Object make_result(const js::Value& result, int id);
+//js::Object make_result(const js::Value& result, int id);
 
 // create a JSON-RPC 2.0 compatible error response object
 js::Object make_error(JSON_RPC error_code, const std::string& error_message, const js::Value& data, int id);
diff --git a/server/security-token.cc b/server/security-token.cc
index 00858fe..63c3401 100644
--- a/server/security-token.cc
+++ b/server/security-token.cc
@@ -65,7 +65,11 @@ std::string create_security_token(const std::string& server_address, unsigned po
 	o.emplace_back("security_token", sec_token );
 	
 	const std::string content = js::write( o, js::pretty_print | js::raw_utf8 ) + '\n';
-	write(fd, content.data(), content.size());
+	const ssize_t ss = write(fd, content.data(), content.size());
+	if(ss<0 || uint64_t(ss)!=content.size())
+	{
+		throw std::runtime_error("Cannot write into security token file \"" + filename + "\": " + std::to_string(errno));
+	}
 	close(fd);
 	
 	return sec_token;