diff --git a/.rubocop.yml b/.rubocop.yml
index 7784404b9..475d4a2e9 100644
--- a/.rubocop.yml
+++ b/.rubocop.yml
@@ -4,7 +4,8 @@ require:
 
 AllCops:
   TargetRailsVersion: 5.0
-  TargetRubyVersion: 2.3
+  TargetRubyVersion: 2.4
+  NewCops: enable
   Exclude:
     - 'gemfiles/vendor/bundle/**/*'
     - 'node_modules/**/*'
@@ -17,12 +18,6 @@ Layout/HashAlignment:
 Layout/LineLength:
   Enabled: false
 
-Lint/RaiseException:
-  Enabled: true
-
-Lint/StructNewOverride:
-  Enabled: true
-
 Metrics/AbcSize:
   Max: 18.36
 
@@ -73,14 +68,5 @@ Style/FormatStringToken:
   Exclude:
     - 'test/**/*'
 
-Style/HashEachMethods:
-  Enabled: true
-
-Style/HashTransformKeys:
-  Enabled: true
-
-Style/HashTransformValues:
-  Enabled: true
-
 Style/IfUnlessModifier:
   Enabled: false
diff --git a/.travis.yml b/.travis.yml
index 0682208f3..6b205a047 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,7 +1,6 @@
 language: ruby
 
 rvm:
-  - 2.3.8
   - 2.4.10
   - 2.5.8
   - 2.6.6
@@ -38,10 +37,6 @@ matrix:
     - rvm: ruby-head
     - gemfile: gemfiles/rails_edge.gemfile
   exclude:
-    - rvm: 2.3.8
-      gemfile: gemfiles/rails_6.0.gemfile
-    - rvm: 2.3.8
-      gemfile: gemfiles/rails_edge.gemfile
     - rvm: 2.4.10
       gemfile: gemfiles/rails_6.0.gemfile
     - rvm: 2.4.10
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 5a536986b..ca48ee30c 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,9 @@
 # Changelog
 
+## master / unreleased
+
+* [FEATURE] Drop Ruby 2.3 support
+
 ## 16.2.0 / 2020-04-10
 
 * [FEATURE] Add jQuery 3.5.0 compatibility ([#779](https://github.com/DavyJonesLocker/client_side_validations/pull/779))
diff --git a/client_side_validations.gemspec b/client_side_validations.gemspec
index e698955d9..29d94ddb3 100644
--- a/client_side_validations.gemspec
+++ b/client_side_validations.gemspec
@@ -23,7 +23,7 @@ Gem::Specification.new do |spec|
   spec.require_paths = ['lib']
 
   spec.platform              = Gem::Platform::RUBY
-  spec.required_ruby_version = '~> 2.3'
+  spec.required_ruby_version = '~> 2.4'
 
   spec.add_dependency 'rails', '>= 5.0.0.1', '< 6.1'
 
@@ -31,16 +31,16 @@ Gem::Specification.new do |spec|
   spec.add_dependency 'js_regex', '~> 3.1'
 
   spec.add_development_dependency 'appraisal', '~> 2.2'
-  spec.add_development_dependency 'byebug', '>= 10.0', '< 12'
-  spec.add_development_dependency 'coveralls_reborn', '>= 0.14.0', '< 0.16'
+  spec.add_development_dependency 'byebug', '~> 11.1'
+  spec.add_development_dependency 'coveralls_reborn', '~> 0.15.1'
   spec.add_development_dependency 'm', '~> 1.5'
   spec.add_development_dependency 'minitest', '~> 5.14'
   spec.add_development_dependency 'mocha', '~> 1.11'
   spec.add_development_dependency 'rake', '~> 13.0'
-  spec.add_development_dependency 'rubocop', '~> 0.81.0'
+  spec.add_development_dependency 'rubocop', '~> 0.82.0'
   spec.add_development_dependency 'rubocop-performance', '~> 1.5'
   spec.add_development_dependency 'rubocop-rails', '~> 2.5'
-  spec.add_development_dependency 'simplecov', '>= 0.17.1', '< 0.19'
+  spec.add_development_dependency 'simplecov', '~> 0.18.5'
   spec.add_development_dependency 'sqlite3', '~> 1.4'
 
   # For QUnit testing