diff --git a/VERSION b/VERSION
index 0ea3a94..0d91a54 100644
--- a/VERSION
+++ b/VERSION
@@ -1 +1 @@
-0.2.0
+0.3.0
diff --git a/lib/jsonapi/deserializable/resource.rb b/lib/jsonapi/deserializable/resource.rb
index c46e4ad..9878ee0 100644
--- a/lib/jsonapi/deserializable/resource.rb
+++ b/lib/jsonapi/deserializable/resource.rb
@@ -88,9 +88,9 @@ def deserialize_id
       end
 
       def deserialize_attrs
-        @attributes
-          .map { |key, val| deserialize_attr(key, val) }
-          .reduce({}, :merge)
+        obj = {}
+        @attributes.each { |key, val| obj.merge!(deserialize_attr(key, val)) }
+        obj
       end
 
       def deserialize_attr(key, val)
@@ -103,9 +103,9 @@ def deserialize_attr(key, val)
       end
 
       def deserialize_rels
-        @relationships
-          .map { |key, val| deserialize_rel(key, val) }
-          .reduce({}, :merge)
+        obj = {}
+        @relationships.each { |key, val| obj.merge!(deserialize_rel(key, val)) }
+        obj
       end
 
       def deserialize_rel(key, val)