diff --git a/Gemfile.lock b/Gemfile.lock
index 1fe6279..25522d1 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -99,7 +99,7 @@ GEM
       coffee-script-source
       execjs
     coffee-script-source (1.12.2)
-    concurrent-ruby (1.0.5)
+    concurrent-ruby (1.1.4)
     connection_pool (2.2.1)
     coveralls (0.8.20)
       json (>= 1.8, < 3)
@@ -201,7 +201,7 @@ GEM
       pry (>= 0.10.4)
     public_suffix (2.0.5)
     puma (3.8.2)
-    rack (2.0.1)
+    rack (2.0.6)
     rack-cors (0.4.1)
     rack-protection (1.5.3)
       rack
@@ -300,7 +300,7 @@ GEM
     spring-watcher-listen (2.0.1)
       listen (>= 2.7, < 4.0)
       spring (>= 1.2, < 3.0)
-    sprockets (3.7.1)
+    sprockets (3.7.2)
       concurrent-ruby (~> 1.0)
       rack (> 1, < 3)
     sprockets-rails (3.2.0)