diff --git a/Gemfile b/Gemfile
index 36df038..4c2021d 100644
--- a/Gemfile
+++ b/Gemfile
@@ -4,5 +4,4 @@ gemspec
 
 gem 'rake'
 gem 'rails'
-gem 'rspec'
-gem 'dalli'
\ No newline at end of file
+gem 'rspec'
\ No newline at end of file
diff --git a/Gemfile.lock b/Gemfile.lock
index 3646f8c..1b62c56 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -1,132 +1,138 @@
 PATH
   remote: .
   specs:
-    rucaptcha (2.3.1)
+    rucaptcha (2.3.2)
       railties (>= 3.2)
 
 GEM
   remote: https://rubygems.org/
   specs:
-    actioncable (5.1.5)
-      actionpack (= 5.1.5)
+    actioncable (5.2.1)
+      actionpack (= 5.2.1)
       nio4r (~> 2.0)
-      websocket-driver (~> 0.6.1)
-    actionmailer (5.1.5)
-      actionpack (= 5.1.5)
-      actionview (= 5.1.5)
-      activejob (= 5.1.5)
+      websocket-driver (>= 0.6.1)
+    actionmailer (5.2.1)
+      actionpack (= 5.2.1)
+      actionview (= 5.2.1)
+      activejob (= 5.2.1)
       mail (~> 2.5, >= 2.5.4)
       rails-dom-testing (~> 2.0)
-    actionpack (5.1.5)
-      actionview (= 5.1.5)
-      activesupport (= 5.1.5)
+    actionpack (5.2.1)
+      actionview (= 5.2.1)
+      activesupport (= 5.2.1)
       rack (~> 2.0)
       rack-test (>= 0.6.3)
       rails-dom-testing (~> 2.0)
       rails-html-sanitizer (~> 1.0, >= 1.0.2)
-    actionview (5.1.5)
-      activesupport (= 5.1.5)
+    actionview (5.2.1)
+      activesupport (= 5.2.1)
       builder (~> 3.1)
       erubi (~> 1.4)
       rails-dom-testing (~> 2.0)
       rails-html-sanitizer (~> 1.0, >= 1.0.3)
-    activejob (5.1.5)
-      activesupport (= 5.1.5)
+    activejob (5.2.1)
+      activesupport (= 5.2.1)
       globalid (>= 0.3.6)
-    activemodel (5.1.5)
-      activesupport (= 5.1.5)
-    activerecord (5.1.5)
-      activemodel (= 5.1.5)
-      activesupport (= 5.1.5)
-      arel (~> 8.0)
-    activesupport (5.1.5)
+    activemodel (5.2.1)
+      activesupport (= 5.2.1)
+    activerecord (5.2.1)
+      activemodel (= 5.2.1)
+      activesupport (= 5.2.1)
+      arel (>= 9.0)
+    activestorage (5.2.1)
+      actionpack (= 5.2.1)
+      activerecord (= 5.2.1)
+      marcel (~> 0.3.1)
+    activesupport (5.2.1)
       concurrent-ruby (~> 1.0, >= 1.0.2)
-      i18n (~> 0.7)
+      i18n (>= 0.7, < 2)
       minitest (~> 5.1)
       tzinfo (~> 1.1)
-    arel (8.0.0)
+    arel (9.0.0)
     builder (3.2.3)
-    concurrent-ruby (1.0.5)
-    concurrent-ruby (1.0.5-java)
-    crass (1.0.3)
-    dalli (2.7.7)
+    concurrent-ruby (1.1.3)
+    crass (1.0.4)
     diff-lcs (1.3)
     erubi (1.7.1)
     globalid (0.4.1)
       activesupport (>= 4.2.0)
-    i18n (0.9.5)
+    i18n (1.1.1)
       concurrent-ruby (~> 1.0)
-    loofah (2.2.2)
+    loofah (2.2.3)
       crass (~> 1.0.2)
       nokogiri (>= 1.5.9)
-    mail (2.7.0)
+    mail (2.7.1)
       mini_mime (>= 0.1.1)
-    method_source (0.9.0)
-    mini_mime (1.0.0)
+    marcel (0.3.3)
+      mimemagic (~> 0.3.2)
+    method_source (0.9.2)
+    mimemagic (0.3.2)
+    mini_mime (1.0.1)
     mini_portile2 (2.3.0)
     minitest (5.11.3)
-    nio4r (2.3.0)
-    nio4r (2.3.0-java)
-    nokogiri (1.8.2)
+    nio4r (2.3.1)
+    nio4r (2.3.1-java)
+    nokogiri (1.8.5)
       mini_portile2 (~> 2.3.0)
-    nokogiri (1.8.2-java)
-    rack (2.0.4)
-    rack-test (1.0.0)
+    nokogiri (1.8.5-java)
+    rack (2.0.6)
+    rack-test (1.1.0)
       rack (>= 1.0, < 3)
-    rails (5.1.5)
-      actioncable (= 5.1.5)
-      actionmailer (= 5.1.5)
-      actionpack (= 5.1.5)
-      actionview (= 5.1.5)
-      activejob (= 5.1.5)
-      activemodel (= 5.1.5)
-      activerecord (= 5.1.5)
-      activesupport (= 5.1.5)
+    rails (5.2.1)
+      actioncable (= 5.2.1)
+      actionmailer (= 5.2.1)
+      actionpack (= 5.2.1)
+      actionview (= 5.2.1)
+      activejob (= 5.2.1)
+      activemodel (= 5.2.1)
+      activerecord (= 5.2.1)
+      activestorage (= 5.2.1)
+      activesupport (= 5.2.1)
       bundler (>= 1.3.0)
-      railties (= 5.1.5)
+      railties (= 5.2.1)
       sprockets-rails (>= 2.0.0)
     rails-dom-testing (2.0.3)
       activesupport (>= 4.2.0)
       nokogiri (>= 1.6)
     rails-html-sanitizer (1.0.4)
       loofah (~> 2.2, >= 2.2.2)
-    railties (5.1.5)
-      actionpack (= 5.1.5)
-      activesupport (= 5.1.5)
+    railties (5.2.1)
+      actionpack (= 5.2.1)
+      activesupport (= 5.2.1)
       method_source
       rake (>= 0.8.7)
-      thor (>= 0.18.1, < 2.0)
+      thor (>= 0.19.0, < 2.0)
     rake (12.3.1)
-    rake-compiler (1.0.4)
+    rake-compiler (1.0.5)
       rake
-    rspec (3.7.0)
-      rspec-core (~> 3.7.0)
-      rspec-expectations (~> 3.7.0)
-      rspec-mocks (~> 3.7.0)
-    rspec-core (3.7.1)
-      rspec-support (~> 3.7.0)
-    rspec-expectations (3.7.0)
+    rspec (3.8.0)
+      rspec-core (~> 3.8.0)
+      rspec-expectations (~> 3.8.0)
+      rspec-mocks (~> 3.8.0)
+    rspec-core (3.8.0)
+      rspec-support (~> 3.8.0)
+    rspec-expectations (3.8.2)
       diff-lcs (>= 1.2.0, < 2.0)
-      rspec-support (~> 3.7.0)
-    rspec-mocks (3.7.0)
+      rspec-support (~> 3.8.0)
+    rspec-mocks (3.8.0)
       diff-lcs (>= 1.2.0, < 2.0)
-      rspec-support (~> 3.7.0)
-    rspec-support (3.7.1)
-    sprockets (3.7.1)
+      rspec-support (~> 3.8.0)
+    rspec-support (3.8.0)
+    sprockets (3.7.2)
       concurrent-ruby (~> 1.0)
       rack (> 1, < 3)
     sprockets-rails (3.2.1)
       actionpack (>= 4.0)
       activesupport (>= 4.0)
       sprockets (>= 3.0.0)
-    thor (0.20.0)
+    thor (0.20.3)
     thread_safe (0.3.6)
     thread_safe (0.3.6-java)
     tzinfo (1.2.5)
       thread_safe (~> 0.1)
-    websocket-driver (0.6.5)
+    websocket-driver (0.7.0)
       websocket-extensions (>= 0.1.0)
-    websocket-driver (0.6.5-java)
+    websocket-driver (0.7.0-java)
       websocket-extensions (>= 0.1.0)
     websocket-extensions (0.1.3)
 
@@ -135,7 +141,6 @@ PLATFORMS
   ruby
 
 DEPENDENCIES
-  dalli
   rails
   rake
   rake-compiler (~> 1)
@@ -143,4 +148,4 @@ DEPENDENCIES
   rucaptcha!
 
 BUNDLED WITH
-   1.16.2
+   1.17.1
diff --git a/spec/spec_helper.rb b/spec/spec_helper.rb
index f53d402..02e0f72 100644
--- a/spec/spec_helper.rb
+++ b/spec/spec_helper.rb
@@ -21,5 +21,5 @@ module Rails
 end
 
 RuCaptcha.configure do
-  self.cache_store = :mem_cache_store
+  self.cache_store = :memory_store
 end