diff --git a/Gemfile.lock b/Gemfile.lock
index 6212f64..5890720 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -60,7 +60,7 @@ GEM
       coffee-script-source
       execjs
     coffee-script-source (1.6.2)
-    concurrent-ruby (1.0.5)
+    concurrent-ruby (1.1.8)
     connection_pool (2.2.1)
     css_parser (1.3.5)
       addressable
@@ -129,7 +129,6 @@ GEM
       treetop (~> 1.4.8)
     method_source (0.8.1)
     mime-types (1.25.1)
-    mimemagic (0.3.0)
     mini_portile2 (2.3.0)
     mongoid (3.1.6)
       activemodel (~> 3.2)
@@ -142,15 +141,15 @@ GEM
     moped (1.5.1)
     multi_json (1.13.1)
     multipart-post (2.0.0)
+    nio4r (2.5.7)
     nokogiri (1.8.2)
       mini_portile2 (~> 2.3.0)
     origin (1.1.0)
-    paperclip (4.3.7)
+    paperclip (4.2.4)
       activemodel (>= 3.2.0)
       activesupport (>= 3.2.0)
       cocaine (~> 0.5.5)
       mime-types
-      mimemagic (= 0.3.0)
     polyglot (0.3.5)
     premailer (1.8.0)
       css_parser (>= 1.3.5)
@@ -162,7 +161,8 @@ GEM
       coderay (~> 1.0.5)
       method_source (~> 0.8)
       slop (~> 3.4)
-    puma (3.6.2)
+    puma (5.3.1)
+      nio4r (~> 2.0)
     rack (1.4.7)
     rack-cache (1.7.1)
       rack (>= 0.4)