diff --git a/.rubocop.yml b/.rubocop.yml
index 7df24557..a58e0422 100644
--- a/.rubocop.yml
+++ b/.rubocop.yml
@@ -33,3 +33,10 @@ Naming:
 
 Style/RegexpLiteral:
   Enabled: false
+
+Style/HashEachMethods:
+  Enabled: true
+Style/HashTransformKeys:
+  Enabled: true
+Style/HashTransformValues:
+  Enabled: true
diff --git a/CHANGELOG.md b/CHANGELOG.md
index af59d0a0..3c16878c 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -45,10 +45,6 @@
 * [#743](https://github.com/ruby-grape/grape-swagger/pull/743): CI: use 2.4.6, 2.5.5 - [@olleolleolle](https://github.com/olleolleolle).
 * [#737](https://github.com/ruby-grape/grape-swagger/pull/737): Add swagger endpoint guard to both doc endpoints - [@urkle](https://github.com/urkle).
 
-#### Changes
-
-* [#749](https://github.com/ruby-grape/grape-swagger/pull/749) Drop support for Ruby 2.3 and below - [@LeFnord](https://github.com/LeFnord).
-
 
 ### 0.32.1 (December 7, 2018)
 
diff --git a/Gemfile b/Gemfile
index daf0ccc4..d3ec7cb3 100644
--- a/Gemfile
+++ b/Gemfile
@@ -20,13 +20,13 @@ group :development, :test do
   gem 'pry', platforms: [:mri]
   gem 'pry-byebug', platforms: [:mri]
 
-  gem 'rack', '~> 2.1'
+  gem 'rack', '~> 2.2'
   gem 'rack-cors'
   gem 'rack-test'
   gem 'rake'
   gem 'rdoc'
   gem 'rspec', '~> 3.9'
-  gem 'rubocop', '~> 0.79', require: false
+  gem 'rubocop', '~> 0.80', require: false
 end
 
 group :test do