diff --git a/Gemfile b/Gemfile
index d7353d1..cd4d9b8 100644
--- a/Gemfile
+++ b/Gemfile
@@ -48,8 +48,8 @@ gem 'houston'
 gem 'kaminari', '~> 0.16.3'
 gem 'rack-cors', :require => 'rack/cors'
 gem 'redis', '~> 3.2.1'
-gem 'sidekiq', '~> 3.4.2'
-gem 'sidekiq-limit_fetch', '~> 2.4.2'
+gem 'sidekiq', '~> 4.0', '>= 4.0.1'
+gem 'sidekiq-limit_fetch', '~> 3.0', '>= 3.0.1'
 gem 'sidekiq_mailer'
 gem 'sidekiq-failures', '~> 0.4.5'
 gem 'sinatra', :require => nil
diff --git a/Gemfile.lock b/Gemfile.lock
index dfabf8f..26fe340 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -103,8 +103,6 @@ GEM
     capistrano3-puma (1.2.1)
       capistrano (~> 3.0)
       puma (>= 2.6)
-    celluloid (0.16.0)
-      timers (~> 4.0.0)
     climate_control (0.0.3)
       activesupport (>= 3.0)
     cocaine (0.5.7)
@@ -120,6 +118,7 @@ GEM
     colorize (0.7.7)
     commander (4.3.5)
       highline (~> 1.7.2)
+    concurrent-ruby (1.0.0)
     connection_pool (2.2.0)
     debug_inspector (0.0.2)
     devise (3.5.2)
@@ -158,7 +157,6 @@ GEM
       activesupport (>= 3.2, < 5)
     hashie (2.0.5)
     highline (1.7.8)
-    hitimes (1.2.3)
     houston (2.2.3)
       commander (~> 4.1)
       json
@@ -294,9 +292,7 @@ GEM
       i18n
       polyamorous (~> 1.2)
     rdoc (4.2.0)
-    redis (3.2.1)
-    redis-namespace (1.5.2)
-      redis (~> 3.0, >= 3.0.4)
+    redis (3.2.2)
     responders (2.1.0)
       railties (>= 4.2.0, < 5)
     rest-client (1.7.3)
@@ -337,16 +333,15 @@ GEM
     sdoc (0.4.1)
       json (~> 1.7, >= 1.7.7)
       rdoc (~> 4.0)
-    sidekiq (3.4.2)
-      celluloid (~> 0.16.0)
+    sidekiq (4.0.1)
+      concurrent-ruby (~> 1.0)
       connection_pool (~> 2.2, >= 2.2.0)
       json (~> 1.0)
       redis (~> 3.2, >= 3.2.1)
-      redis-namespace (~> 1.5, >= 1.5.2)
     sidekiq-failures (0.4.5)
       sidekiq (>= 2.16.0)
-    sidekiq-limit_fetch (2.4.2)
-      sidekiq (>= 2.6.5, < 4.0)
+    sidekiq-limit_fetch (3.0.1)
+      sidekiq (>= 4)
     sidekiq_mailer (0.0.8)
       actionmailer (>= 3.0)
       activesupport (>= 3.0)
@@ -370,8 +365,6 @@ GEM
     thor (0.19.1)
     thread_safe (0.3.5)
     tilt (2.0.1)
-    timers (4.0.4)
-      hitimes
     turbolinks (2.5.3)
       coffee-rails
     tzinfo (1.2.2)
@@ -445,9 +438,9 @@ DEPENDENCIES
   rspec-sidekiq
   sass-rails (~> 5.0)
   sdoc (~> 0.4.0)
-  sidekiq (~> 3.4.2)
+  sidekiq (~> 4.0, >= 4.0.1)
   sidekiq-failures (~> 0.4.5)
-  sidekiq-limit_fetch (~> 2.4.2)
+  sidekiq-limit_fetch (~> 3.0, >= 3.0.1)
   sidekiq_mailer
   sinatra
   spring