diff --git a/include/mbgl/util/factory.hpp b/include/mbgl/util/factory.hpp
index eb1c22933..1ffcac6f9 100644
--- a/include/mbgl/util/factory.hpp
+++ b/include/mbgl/util/factory.hpp
@@ -1,10 +1,9 @@
 #ifndef MBGL_UTIL_FACTORY_HPP
 #define MBGL_UTIL_FACTORY_HPP
 
-#include "singleton.hpp"
-
 // stl
 #include <stdexcept>
+#include <mutex>
 #include <map>
 
 namespace mbgl { namespace util {
@@ -14,27 +13,28 @@ template
 typename product_type,
 typename key_type,
 typename ...Args >
-class factory : public singleton<factory <product_type,
-                                          key_type,
-                                          Args...> >
+class factory
 {
-private:
+public:
     using product_creator = product_type* (*) (Args...);
     using product_map = std::map<key_type,product_creator>;
-    product_map map_;
+    static product_map map_;
+    static std::mutex mutex_;
 public:
 
-    bool register_product(key_type const& key, product_creator creator)
+    static bool register_product(key_type const& key, product_creator creator)
     {
+        std::unique_lock<std::mutex> lock(mutex_);
         return map_.insert(typename product_map::value_type(key,creator)).second;
     }
 
-    bool unregister_product(const key_type& key)
+    static bool unregister_product(const key_type& key)
     {
+        std::unique_lock<std::mutex> lock(mutex_);
         return map_.erase(key)==1;
     }
 
-    product_type* create_object(key_type const& key, Args...args)
+    static product_type* create_object(key_type const& key, Args...args)
     {
         typename product_map::const_iterator pos=map_.find(key);
         if (pos!=map_.end())
@@ -45,6 +45,11 @@ public:
     }
 };
 
+template <typename product_type, typename key_type, typename ...Args>
+typename factory<product_type, key_type, Args...>::product_map factory<product_type, key_type, Args...>::map_;
+template <typename product_type, typename key_type, typename ...Args>
+typename std::mutex factory<product_type, key_type, Args...>::mutex_;
+
 }}
 
 #endif
diff --git a/include/mbgl/util/image_reader.hpp b/include/mbgl/util/image_reader.hpp
index 4e8043946..144127b76 100644
--- a/include/mbgl/util/image_reader.hpp
+++ b/include/mbgl/util/image_reader.hpp
@@ -38,11 +38,9 @@ struct image_reader : private noncopyable
 template <typename...Args>
 bool register_image_reader(std::string const& type, image_reader* (* fun)(Args...))
 {
-    return factory<image_reader,std::string, Args...>::instance().register_product(type, fun);
+    return factory<image_reader,std::string, Args...>::register_product(type, fun);
 }
 
-//image_reader* get_image_reader(std::string const& file,std::string const& type);
-//image_reader* get_image_reader(std::string const& file);
 image_reader* get_image_reader(char const* data, size_t size);
 
 }}
diff --git a/platform/default/image_reader.cpp b/platform/default/image_reader.cpp
index 75d7b0c13..53ab5758a 100644
--- a/platform/default/image_reader.cpp
+++ b/platform/default/image_reader.cpp
@@ -43,25 +43,10 @@ image_reader* get_image_reader(char const* data, size_t size)
     boost::optional<std::string> type = type_from_bytes(data,size);
     if (type)
     {
-        return factory<image_reader,std::string,char const*,size_t>::instance().create_object(*type, data,size);
+        return factory<image_reader,std::string,char const*,size_t>::create_object(*type, data,size);
     }
     else
         throw image_reader_exception("image_reader: can't determine type from input data");
 }
 
-//image_reader* get_image_reader(std::string const& filename,std::string const& type)
-//{
-//    return factory<image_reader,std::string,std::string const&>::instance().create_object(type,filename);
-//}
-
-//image_reader* get_image_reader(std::string const& filename)
-//{
-    //boost::optional<std::string> type = type_from_filename(filename);
-    //if (type)
-    //{
-    //    return factory<image_reader,std::string,std::string const&>::instance().create_object(*type,filename);
-    //}
-//    return 0;
-//}
-
 }}