this is needed too

Gemfile.lock

@@ -5,14 +5,6 @@ GIT
     metriks-librato_metrics (1.0.5)
       metriks (>= 0.9.9.6)
 
-GIT
-  remote: git://github.com/rack/rack-contrib.git
-  revision: ea0c82dc3a6353542b7fe0cbd262c43378e28b31
-  specs:
-    rack-contrib (1.4.0)
-      git-version-bump (~> 0.15)
-      rack (~> 1.4)
-
 GIT
   remote: git://github.com/rkh/mustermann.git
   revision: 9611951c5c789ad8227a740ae142c157a8bf7401
@@ -264,6 +256,9 @@ GEM
     rack (1.4.7)
     rack-attack (4.4.1)
       rack
+    rack-contrib (1.4.0)
+      git-version-bump (~> 0.15)
+      rack (~> 1.4)
     rack-protection (1.5.3)
       rack
     rack-ssl (1.3.4)
@@ -387,7 +382,7 @@ DEPENDENCIES
   pry
   rack-attack
   rack-cache!
-  rack-contrib!
+  rack-contrib
   rake (~> 0.9.2)
   rb-fsevent (~> 0.9.1)
   rerun
@@ -413,4 +408,4 @@ DEPENDENCIES
   yard-sinatra!
 
 BUNDLED WITH
-   1.12.4
+   1.12.5