diff --git a/.gitignore b/.gitignore
index 8624f93..1bb1e05 100644
--- a/.gitignore
+++ b/.gitignore
@@ -5,3 +5,4 @@ bin
 *.gemfile.lock
 .ruby-version
 .ruby-gemset
+.byebug_history
diff --git a/.rubocop.yml b/.rubocop.yml
new file mode 100644
index 0000000..eea40b4
--- /dev/null
+++ b/.rubocop.yml
@@ -0,0 +1,58 @@
+inherit_mode:
+  merge:
+    - Exclude
+
+AllCops:
+  TargetRubyVersion: 2.3
+  DisabledByDefault: true
+  Exclude:
+    - "examples/instrumentation.rb"
+    # Remove the following line once we are able to make bundler install gems to <PROJECT_ROOT>/vendor/bundle instead
+    # of <PROJECT_ROOT>/gemfiles/vendor/bundle during TravisCI builds. The reason that happens for now is because
+    # bundler 1.x only installs relative to the Gemfile (which during CI builds is always one inside gemfiles/ folder)
+    # instead of the CWD. Bundler 2.x will add support to install relative to CWD
+    # (see https://github.com/bundler/bundler/pull/5803).
+    - "gemfiles/vendor/**/*"
+
+Bundler:
+  Enabled: true
+
+Gemspec:
+  Enabled: true
+
+Layout:
+  Enabled: true
+
+Lint:
+  Enabled: true
+
+Naming:
+  Enabled: true
+  Exclude:
+    - "lib/rack/attack/path_normalizer.rb"
+
+Performance:
+  Enabled: true
+
+Security:
+  Enabled: true
+
+Lint:
+  Enabled: true
+
+Style/BlockDelimiters:
+  Enabled: true
+
+Style/BracesAroundHashParameters:
+  Enabled: true
+
+Style/FrozenStringLiteralComment:
+  Enabled: true
+
+Style/RedundantFreeze:
+  Enabled: true
+
+# TODO
+# Remove cop disabling and fix offenses
+Lint/HandleExceptions:
+  Enabled: false
diff --git a/.travis.yml b/.travis.yml
index 9eb7762..46bb12f 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,20 +1,42 @@
 language: ruby
+cache: bundler
+
 rvm:
-  - 2.5.0
-  - 2.4.3
-  - 2.3.6
-  - 2.2.9
-  - jruby-9.1.14.0
+  - 2.6.0-preview2
+  - 2.5.1
+  - 2.4.4
+  - 2.3.7
+  - jruby-9.1.16.0
 
 before_install:
-  - gem update --system
+  # For jruby we need to stick with rubygems 2.7.4 until
+  # https://github.com/rubygems/rubygems/issues/2188
+  # is fixed and released.
+  #
+  # Without this workaround, for jruby builds, rubygems
+  # activates jruby stdlib minitest (v5.4.1) instead of the
+  # bundled version (v5.11.3).
+  - if [ "${TRAVIS_RUBY_VERSION:0:5}" = "jruby" ]; then gem update --system 2.7.4; else gem update --system; fi
   - gem install bundler
 
 gemfile:
+  - gemfiles/rack_2_0.gemfile
+  - gemfiles/rack_1_6.gemfile
+  - gemfiles/rails_5_2.gemfile
   - gemfiles/rails_5_1.gemfile
-  - gemfiles/rails_5_0.gemfile
   - gemfiles/rails_4_2.gemfile
   - gemfiles/dalli2.gemfile
+  - gemfiles/connection_pool_dalli.gemfile
+  - gemfiles/active_support_redis_cache_store.gemfile
+  - gemfiles/active_support_redis_cache_store_pooled.gemfile
+  - gemfiles/redis_store.gemfile
+  - gemfiles/active_support_redis_store.gemfile
+
+matrix:
+  allow_failures:
+    - rvm: 2.6.0-preview2
+
+  fast_finish: true
 
 services:
   - redis
diff --git a/Appraisals b/Appraisals
index 56fadfc..2cabba7 100644
--- a/Appraisals
+++ b/Appraisals
@@ -1,18 +1,65 @@
-appraise 'rails_5-1' do
-  gem 'activesupport', '~> 5.1.0'
-  gem 'actionpack', '~> 5.1.0'
+# frozen_string_literal: true
+
+appraise "rack_2_0" do
+  gem "rack", "~> 2.0.4"
 end
 
-appraise 'rails_5-0' do
-  gem 'activesupport', '~> 5.0.0'
-  gem 'actionpack', '~> 5.0.0'
+appraise "rack_1_6" do
+  # Override activesupport and actionpack version constraints by making
+  # it more loose so it's compatible with rack 1.6.x
+  gem "actionpack", ">= 4.2"
+  gem "activesupport", ">= 4.2"
+
+  gem "rack", "~> 1.6.9"
+
+  # Override rack-test version constraint by making it more loose
+  # so it's compatible with actionpack 4.2.x
+  gem "rack-test", ">= 0.6"
+end
+
+appraise 'rails_5-2' do
+  gem 'actionpack', '~> 5.2.0'
+  gem 'activesupport', '~> 5.2.0'
+end
+
+appraise 'rails_5-1' do
+  gem 'actionpack', '~> 5.1.0'
+  gem 'activesupport', '~> 5.1.0'
 end
 
 appraise 'rails_4-2' do
-  gem 'activesupport', '~> 4.2.0'
   gem 'actionpack', '~> 4.2.0'
+  gem 'activesupport', '~> 4.2.0'
+
+  # Override rack-test version constraint by making it more loose
+  # so it's compatible with actionpack 4.2.x
+  gem "rack-test", ">= 0.6"
 end
 
 appraise 'dalli2' do
   gem 'dalli', '~> 2.0'
 end
+
+appraise "connection_pool_dalli" do
+  gem "connection_pool", "~> 2.2"
+  gem "dalli", "~> 2.7"
+end
+
+appraise "active_support_redis_cache_store" do
+  gem "activesupport", "~> 5.2.0"
+  gem "redis", "~> 4.0"
+end
+
+appraise "active_support_redis_cache_store_pooled" do
+  gem "activesupport", "~> 5.2.0"
+  gem "connection_pool", "~> 2.2"
+  gem "redis", "~> 4.0"
+end
+
+appraise "redis_store" do
+  gem "redis-store", "~> 1.5"
+end
+
+appraise "active_support_redis_store" do
+  gem "redis-activesupport", "~> 5.0"
+end
diff --git a/CHANGELOG.md b/CHANGELOG.md
index cec9633..c8c798a 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,84 +1,147 @@
-# Changlog
+# Changelog
 
-## [New Releases here](https://github.com/kickstarter/rack-attack/releases)
+All notable changes to this project will be documented in this file.
 
-This file is kept for historical documentation.
+## [Unreleased]
 
-## v5.0.0.beta1 4 July 2016
+_No significant changes since last release yet. Stay tuned_ :radio:
 
-  - Deprecate `whitelist`/`blacklist` in favor of `safelist`/`blocklist`. (#181,
+## [5.3.2] - 2018-06-25
+
+### Fixed
+
+- Don't raise exception `The Redis cache store requires the redis gem` when using [`ActiveSupport::Cache::MemoryStore`](http://api.rubyonrails.org/classes/ActiveSupport/Cache/MemoryStore.html) as a cache store backend
+
+## [5.3.1] - 2018-06-20
+
+### Fixed
+
+- Make [`ActiveSupport::Cache::RedisCacheStore`](http://api.rubyonrails.org/classes/ActiveSupport/Cache/RedisCacheStore.html) also work as excepted when initialized with pool options (e.g. `pool_size`)
+
+## [5.3.0] - 2018-06-19
+
+### Added
+
+- Add support for [`ActiveSupport::Cache::RedisCacheStore`](http://api.rubyonrails.org/classes/ActiveSupport/Cache/RedisCacheStore.html) as a store backend ([#340](https://github.com/kickstarter/rack-attack/pull/340) and [#350](https://github.com/kickstarter/rack-attack/pull/350))
+
+## [5.2.0] - 2018-03-29
+
+### Added
+
+- Shorthand for blocking an IP address `Rack::Attack.blocklist_ip("1.2.3.4")` ([#320](https://github.com/kickstarter/rack-attack/pull/320))
+- Shorthand for blocking an IP subnet `Rack::Attack.blocklist_ip("1.2.0.0/16")` ([#320](https://github.com/kickstarter/rack-attack/pull/320))
+- Shorthand for safelisting an IP address `Rack::Attack.safelist_ip("5.6.7.8")` ([#320](https://github.com/kickstarter/rack-attack/pull/320))
+- Shorthand for safelisting an IP subnet `Rack::Attack.safelist_ip("5.6.0.0/16")` ([#320](https://github.com/kickstarter/rack-attack/pull/320))
+- Throw helpful error message when using `allow2ban` but cache store is misconfigured ([#315](https://github.com/kickstarter/rack-attack/issues/315))
+- Throw helpful error message when using `fail2ban` but cache store is misconfigured ([#315](https://github.com/kickstarter/rack-attack/issues/315))
+
+## [5.1.0] - 2018-03-10
+
+  - Fixes edge case bug when using ruby 2.5.0 and redis [#253](https://github.com/kickstarter/rack-attack/issues/253) ([#271](https://github.com/kickstarter/rack-attack/issues/271))
+  - Throws errors with better semantics when missing or misconfigured store caches to aid in developers debugging their configs ([#274](https://github.com/kickstarter/rack-attack/issues/274))
+  - Removed legacy code that was originally intended for Rails 3 apps ([#264](https://github.com/kickstarter/rack-attack/issues/264))
+
+## [5.0.1] - 2016-08-11
+
+  - Fixes arguments passed to deprecated internal methods. ([#198](https://github.com/kickstarter/rack-attack/issues/198))
+
+## [5.0.0] - 2016-08-09
+
+  - Deprecate `whitelist`/`blacklist` in favor of `safelist`/`blocklist`. ([#181](https://github.com/kickstarter/rack-attack/issues/181),
     thanks @renee-travisci).  To upgrade and fix deprecations, find and replace instances of `whitelist` and `blacklist` with `safelist` and `blocklist`. If you reference `rack.attack.match_type`, note that it will have values like `:safelist`/`:blocklist`.
   - Remove test coverage for unsupported ruby dependencies: ruby 2.0, activesupport 3.2/4.0, and dalli 1.
 
-## v4.4.1 17 Feb 2016
+## [4.4.1] - 2016-02-17
 
   - Fix a bug affecting apps using Redis::Store and ActiveSupport that could generate an error
-    saying dalli was a required dependency. I learned all about ActiveSupport autoloading. (#165)
+    saying dalli was a required dependency. I learned all about ActiveSupport autoloading. ([#165](https://github.com/kickstarter/rack-attack/issues/165))
 
-## v4.4.0 - 10 Feb 2016
+## [4.4.0] - 2016-02-10
 
-  - New: support for MemCacheStore (#153). Thanks @elhu.
+  - New: support for MemCacheStore ([#153](https://github.com/kickstarter/rack-attack/issues/153)). Thanks @elhu.
   - Some documentation and test harness improvements.
 
-## v4.3.1 - 18 Dec 2015
+## [4.3.1] - 2015-12-18
   - SECURITY FIX: Normalize request paths when using ActionDispatch. Thanks
     Andres Riancho at @includesecurity for reporting it.
   - Remove support for ruby 1.9.x
   - Add Code of Conduct
   - Several documentation and testing improvements
 
-## v4.3.0 - 22 May 2015
+## [4.3.0] - 2015-05-22
 
   - Redis proxy passes `raw: true` (thanks @stanhu)
   - Redis supports `delete` method to be consistent with Dalli (thanks @stanhu)
   - Support the ability to reset Fail2Ban count and ban flag (thanks @stanhu)
 
-## v4.2.0 - 26 Oct 2014
+## [4.2.0] - 2014-10-26
  - Throttle's `period` argument now takes a proc as well as a number (thanks @gsamokovarov)
  - Invoke the `#call` method on `blocklist_response` and `throttle_response` instead of `#[]`, as per the Rack spec. (thanks @gsamokovarov)
 
-## v4.1.1 - 11 Sept 2014
+## [4.1.1] - 2014-09-11
  - Fix a race condition in throttles that could allow more requests than intended.
 
-## v4.1.0 - 22 May 2014
+## [4.1.0] - 2014-05-22
  - Tracks take an optional limit and period to only notify once a threshold
    is reached (similar to throttles). Thanks @chiliburger!
  - Default throttled & blocklist responses have Content-Type: text/plain
  - Rack::Attack.clear! resets tracks
 
-## v4.0.1 - 14 May 2014
- * Add throttle discriminator to rack env (thanks @blahed)
+## [4.0.1] - 2014-05-14
+ - Add throttle discriminator to rack env (thanks @blahed)
 
-## v4.0.0 - 28 April 2014
- * Implement proxy for Dalli with better Memcachier support. (thanks @hakanensari)
- * Rack::Attack.new returns an instance to ease testing. (thanks @stevehodgkiss)
+## [4.0.0] - 2014-04-28
+ - Implement proxy for Dalli with better Memcachier support. (thanks @hakanensari)
+ - Rack::Attack.new returns an instance to ease testing. (thanks @stevehodgkiss)
    [Changing a module to a class is not backwards compatible, hence v4.0.0.]
- * Use Rack::Attack::Request subclass of Rack::Request for easier extending (thanks @tristandunn)
- * Test more dalli versions.
+ - Use Rack::Attack::Request subclass of Rack::Request for easier extending (thanks @tristandunn)
+ - Test more dalli versions.
 
-## v3.0.0 - 15 March 2014
- * Change default blocklisted response to 403 Forbidden (thanks @carpodaster).
- * Fail gracefully when Redis store is not available; rescue exeption and don't
+## [3.0.0] - 2014-03-15
+ - Change default blocklisted response to 403 Forbidden (thanks @carpodaster).
+ - Fail gracefully when Redis store is not available; rescue exeption and don't
    throttle request. (thanks @wkimeria)
- * TravisCI runs integration tests.
+ - TravisCI runs integration tests.
 
-## v2.3.0 - 11 October 2013
- * Allow throttle `limit` argument to be a proc. (thanks @lunks)
- * Add Allow2Ban, complement of Fail2Ban. (thanks @jormon)
- * Improved TravisCI testing
+## [2.3.0] - 2013-10-11
+ - Allow throttle `limit` argument to be a proc. (thanks @lunks)
+ - Add Allow2Ban, complement of Fail2Ban. (thanks @jormon)
+ - Improved TravisCI testing
 
-## v2.2.1 - 13 August 2013
- * Add license to gemspec
- * Support ruby version 1.9.2
- * Change default blocklisted response code from 503 to 401; throttled response
+## [2.2.1] - 2013-08-13
+ - Add license to gemspec
+ - Support ruby version 1.9.2
+ - Change default blocklisted response code from 503 to 401; throttled response
    from 503 to 429.
 
-## v2.2.0 - 20 June 2013
- * Fail2Ban filtering. See README for details. Thx @madlep!
- * Introduce StoreProxy to more cleanly abstract cache stores. Thx @madlep.
+## [2.2.0] - 2013-06-20
+ - Fail2Ban filtering. See README for details. Thx @madlep!
+ - Introduce StoreProxy to more cleanly abstract cache stores. Thx @madlep.
 
-## v2.1.1 - 16 May 2013
- * Start keeping changelog
- * Fix `Redis::CommandError` when using ActiveSupport numeric extensions (e.g. `1.second`)
- * Remove unused variable
- * Extract mandatory options to constants
+## 2.1.1 - 2013-05-16
+ - Start keeping changelog
+ - Fix `Redis::CommandError` when using ActiveSupport numeric extensions (e.g. `1.second`)
+ - Remove unused variable
+ - Extract mandatory options to constants
+
+[Unreleased]: https://github.com/kickstarter/rack-attack/compare/v5.3.2...HEAD/
+[5.3.2]: https://github.com/kickstarter/rack-attack/compare/v5.3.1...v5.3.2/
+[5.3.1]: https://github.com/kickstarter/rack-attack/compare/v5.3.0...v5.3.1/
+[5.3.0]: https://github.com/kickstarter/rack-attack/compare/v5.2.0...v5.3.0/
+[5.2.0]: https://github.com/kickstarter/rack-attack/compare/v5.1.0...v5.2.0/
+[5.1.0]: https://github.com/kickstarter/rack-attack/compare/v5.0.1...v5.1.0/
+[5.0.1]: https://github.com/kickstarter/rack-attack/compare/v5.0.0...v5.0.1/
+[5.0.0]: https://github.com/kickstarter/rack-attack/compare/v4.4.1...v5.0.0/
+[4.4.1]: https://github.com/kickstarter/rack-attack/compare/v4.4.0...v4.4.1/
+[4.4.0]: https://github.com/kickstarter/rack-attack/compare/v4.3.1...v4.4.0/
+[4.3.1]: https://github.com/kickstarter/rack-attack/compare/v4.3.0...v4.3.1/
+[4.3.0]: https://github.com/kickstarter/rack-attack/compare/v4.2.0...v4.3.0/
+[4.2.0]: https://github.com/kickstarter/rack-attack/compare/v4.1.1...v4.2.0/
+[4.1.1]: https://github.com/kickstarter/rack-attack/compare/v4.1.0...v4.1.1/
+[4.1.0]: https://github.com/kickstarter/rack-attack/compare/v4.0.1...v4.1.0/
+[4.0.1]: https://github.com/kickstarter/rack-attack/compare/v4.0.0...v4.0.1/
+[4.0.0]: https://github.com/kickstarter/rack-attack/compare/v3.0.0...v4.0.0/
+[3.0.0]: https://github.com/kickstarter/rack-attack/compare/v2.3.0...v3.0.0/
+[2.3.0]: https://github.com/kickstarter/rack-attack/compare/v2.2.1...v2.3.0/
+[2.2.1]: https://github.com/kickstarter/rack-attack/compare/v2.2.0...v2.2.1/
+[2.2.0]: https://github.com/kickstarter/rack-attack/compare/v2.1.1...v2.2.0/
diff --git a/CODE_OF_CONDUCT.md b/CODE_OF_CONDUCT.md
index ad44a62..a05c39e 100644
--- a/CODE_OF_CONDUCT.md
+++ b/CODE_OF_CONDUCT.md
@@ -18,4 +18,4 @@ Instances of abusive, harassing, or otherwise unacceptable behavior may be repor
 
 :hand: :page_with_curl:
 
-This Code of Conduct is adapted from the [Contributor Covenant](http://contributor-covenant.org) (v1.0.0), available at [http://contributor-covenant.org/version/1/0/0/](http://contributor-covenant.org/version/1/0/0/)
+This Code of Conduct is adapted from the [Contributor Covenant](https://www.contributor-covenant.org) (v1.0.0), available at [https://www.contributor-covenant.org/version/1/0/0/](https://www.contributor-covenant.org/version/1/0/0/)
diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
new file mode 100644
index 0000000..d664561
--- /dev/null
+++ b/CONTRIBUTING.md
@@ -0,0 +1,26 @@
+# Rack::Attack: Contributing
+
+Thank you for considering contributing to Rack::Attack.
+
+This project is intended to be a safe, welcoming space for collaboration, and contributors are expected to adhere to the [Code of Conduct](CODE_OF_CONDUCT.md).
+
+## How can I help?
+
+Any of the following is greatly appreciated:
+
+* Helping users by answering to their [questions](https://github.com/kickstarter/rack-attack/issues?q=is%3Aopen+is%3Aissue+label%3A%22type%3A+question%22)
+* Helping users troubleshoot their [error reports](https://github.com/kickstarter/rack-attack/issues?q=is%3Aissue+is%3Aopen+label%3A%22type%3A+error+report%22) to figure out if the error is caused by an actual bug or some misconfiguration
+* Giving feedback by commenting in other users [feature requests](https://github.com/kickstarter/rack-attack/issues?q=is%3Aissue+is%3Aopen+label%3A%22type%3A+feature+request%22)
+* Reporting an error you are experiencing
+* Suggesting a new feature you think it would be useful for many users
+* If you want to work on fixing an actual issue and you don't know where to start, those labeled [good first issue](https://github.com/kickstarter/rack-attack/issues?q=is%3Aissue+is%3Aopen+label%3A%22good+first+issue%22) may be a good choice
+
+## Style Guide
+
+As an effort to keep the codebase consistent, we encourage the use of [Rubocop](https://github.com/bbatsov/rubocop).
+This tool helps us abstract most of the decisions we have to make when coding.
+
+To check your code, simply type `bundle exec rubocop` in the shell. The resulting output are all the offenses currently present in the code.
+
+It is highly recommended that you integrate a linter with your editor.
+This way you receive real time feedback about your code. Most editors have some kind of plugin for that.
diff --git a/Gemfile b/Gemfile
index 5d00c12..7f4f5e9 100644
--- a/Gemfile
+++ b/Gemfile
@@ -1,9 +1,5 @@
+# frozen_string_literal: true
+
 source 'https://rubygems.org'
 
 gemspec
-
-group :development do
-  gem 'pry'
-  gem 'guard' # NB: this is necessary in newer versions
-  gem 'guard-minitest'
-end
diff --git a/Guardfile b/Guardfile
deleted file mode 100644
index ebf900b..0000000
--- a/Guardfile
+++ /dev/null
@@ -1,10 +0,0 @@
-# A sample Guardfile
-# More info at https://github.com/guard/guard#readme
-
-guard :minitest do
-  # with Minitest::Spec
-  watch(%r{^spec/(.*)_spec\.rb$})
-  watch(%r{^lib/(.+)\.rb$})         { |m| "spec/#{m[1]}_spec.rb" }
-  watch(%r{^spec/spec_helper\.rb$}) { 'spec' }
-end
-
diff --git a/README.md b/README.md
index b5381e7..9a09558 100644
--- a/README.md
+++ b/README.md
@@ -1,63 +1,340 @@
-# Rack::Attack!!!
+# Rack::Attack
+
 *Rack middleware for blocking & throttling abusive requests*
 
-Rack::Attack is a rack middleware to protect your web app from bad clients.
-It allows *safelisting*, *blocklisting*, *throttling*, and *tracking* based on arbitrary properties of the request.
+Protect your Rails and Rack apps from bad clients. Rack::Attack lets you easily decide when to *allow*, *block* and *throttle* based on properties of the request.
 
-Throttle and fail2ban state is stored in a configurable cache (e.g. `Rails.cache`), presumably backed by memcached or redis ([at least gem v3.0.0](https://rubygems.org/gems/redis)).
+See the [Backing & Hacking blog post](https://www.kickstarter.com/backing-and-hacking/rack-attack-protection-from-abusive-clients) introducing Rack::Attack.
 
-See the [Backing & Hacking blog post](http://www.kickstarter.com/backing-and-hacking/rack-attack-protection-from-abusive-clients) introducing Rack::Attack.
-
-[![Gem Version](https://badge.fury.io/rb/rack-attack.svg)](http://badge.fury.io/rb/rack-attack)
+[![Gem Version](https://badge.fury.io/rb/rack-attack.svg)](https://badge.fury.io/rb/rack-attack)
 [![Build Status](https://travis-ci.org/kickstarter/rack-attack.svg?branch=master)](https://travis-ci.org/kickstarter/rack-attack)
 [![Code Climate](https://codeclimate.com/github/kickstarter/rack-attack.svg)](https://codeclimate.com/github/kickstarter/rack-attack)
 
-## Looking for maintainers
-
-I'm looking for new maintainers to help me support Rack::Attack. Check out
-[issue #219 for details](https://github.com/kickstarter/rack-attack/issues/219).
-
 ## Getting started
 
-Install the [rack-attack](http://rubygems.org/gems/rack-attack) gem; or add it to your Gemfile with bundler:
+### 1. Installing
+
+Add this line to your application's Gemfile:
 
 ```ruby
 # In your Gemfile
+
 gem 'rack-attack'
 ```
-Tell your app to use the Rack::Attack middleware.
-For Rails apps:
+
+And then execute:
+
+    $ bundle
+
+Or install it yourself as:
+
+    $ gem install rack-attack
+
+### 2. Plugging into the application
+
+Then tell your ruby web application to use rack-attack as a middleware.
+
+a) For __rails__ applications:
 
 ```ruby
 # In config/application.rb
+
 config.middleware.use Rack::Attack
 ```
 
-Or for Rackup files:
+b) For __rack__ applications:
 
 ```ruby
 # In config.ru
+
+require "rack/attack"
 use Rack::Attack
 ```
 
-Add a `rack-attack.rb` file to `config/initializers/`:
-```ruby
-# In config/initializers/rack-attack.rb
-class Rack::Attack
-  # your custom configuration...
-end
-```
+__IMPORTANT__: By default, rack-attack won't perform any blocking or throttling, until you specifically tell it what to protect against by configuring some rules.
+
+## Usage
 
 *Tip:* The example in the wiki is a great way to get started:
 [Example Configuration](https://github.com/kickstarter/rack-attack/wiki/Example-Configuration)
 
-Optionally configure the cache store for throttling or fail2ban filtering:
+Define rules by calling `Rack::Attack` public methods, in any file that runs when your application is being initialized. For rails applications this means creating a new file named `config/initializers/rack_attack.rb` and writing your rules there.
+
+### Safelisting
+
+Safelists have the most precedence, so any request matching a safelist would be allowed despite matching any number of blocklists or throttles.
+
+#### `safelist_ip(ip_address_string)`
+
+E.g.
+
+```ruby
+# config/initializers/rack_attack.rb (for rails app)
+
+Rack::Attack.safelist_ip("5.6.7.8")
+```
+
+#### `safelist_ip(ip_subnet_string)`
+
+E.g.
+
+```ruby
+# config/initializers/rack_attack.rb (for rails app)
+
+Rack::Attack.safelist_ip("5.6.7.0/24")
+```
+
+#### `safelist(name, &block)`
+
+Name your custom safelist and make your ruby-block argument return a truthy value if you want the request to be blocked, and falsy otherwise.
+
+The request object is a [Rack::Request](http://www.rubydoc.info/gems/rack/Rack/Request).
+
+E.g.
+
+```ruby
+# config/initializers/rack_attack.rb (for rails apps)
+
+# Provided that trusted users use an HTTP request header named APIKey
+Rack::Attack.safelist("mark any authenticated access safe") do |request|
+  # Requests are allowed if the return value is truthy
+  request.env["APIKey"] == "secret-string"
+end
+
+# Always allow requests from localhost
+# (blocklist & throttles are skipped)
+Rack::Attack.safelist('allow from localhost') do |req|
+  # Requests are allowed if the return value is truthy
+  '127.0.0.1' == req.ip || '::1' == req.ip
+end
+```
+
+### Blocking
+
+#### `blocklist_ip(ip_address_string)`
+
+E.g.
+
+```ruby
+# config/initializers/rack_attack.rb (for rails apps)
+
+Rack::Attack.blocklist_ip("1.2.3.4")
+```
+
+#### `blocklist_ip(ip_subnet_string)`
+
+E.g.
+
+```ruby
+# config/initializers/rack_attack.rb (for rails apps)
+
+Rack::Attack.blocklist_ip("1.2.0.0/16")
+```
+
+#### `blocklist(name, &block)`
+
+Name your custom blocklist and make your ruby-block argument return a truthy value if you want the request to be blocked, and falsy otherwise.
+
+The request object is a [Rack::Request](http://www.rubydoc.info/gems/rack/Rack/Request).
+
+E.g.
+
+```ruby
+# config/initializers/rack_attack.rb (for rails apps)
+
+Rack::Attack.blocklist("block all access to admin") do |request|
+  # Requests are blocked if the return value is truthy
+  request.path.start_with?("/admin")
+end
+
+Rack::Attack.blocklist('block bad UA logins') do |req|
+  req.path == '/login' && req.post? && req.user_agent == 'BadUA'
+end
+```
+
+#### Fail2Ban
+
+`Fail2Ban.filter` can be used within a blocklist to block all requests from misbehaving clients.
+This pattern is inspired by [fail2ban](https://www.fail2ban.org/wiki/index.php/Main_Page).
+See the [fail2ban documentation](https://www.fail2ban.org/wiki/index.php/MANUAL_0_8#Jail_Options) for more details on
+how the parameters work.  For multiple filters, be sure to put each filter in a separate blocklist and use a unique discriminator for each fail2ban filter.
+
+Fail2ban state is stored in a [configurable cache](#cache-store-configuration) (which defaults to `Rails.cache` if present).
+
+```ruby
+# Block suspicious requests for '/etc/password' or wordpress specific paths.
+# After 3 blocked requests in 10 minutes, block all requests from that IP for 5 minutes.
+Rack::Attack.blocklist('fail2ban pentesters') do |req|
+  # `filter` returns truthy value if request fails, or if it's from a previously banned IP
+  # so the request is blocked
+  Rack::Attack::Fail2Ban.filter("pentesters-#{req.ip}", maxretry: 3, findtime: 10.minutes, bantime: 5.minutes) do
+    # The count for the IP is incremented if the return value is truthy
+    CGI.unescape(req.query_string) =~ %r{/etc/passwd} ||
+    req.path.include?('/etc/passwd') ||
+    req.path.include?('wp-admin') ||
+    req.path.include?('wp-login')
+
+  end
+end
+```
+
+Note that `Fail2Ban` filters are not automatically scoped to the blocklist, so when using multiple filters in an application the scoping must be added to the discriminator e.g. `"pentest:#{req.ip}"`.
+
+#### Allow2Ban
+
+`Allow2Ban.filter` works the same way as the `Fail2Ban.filter` except that it *allows* requests from misbehaving
+clients until such time as they reach maxretry at which they are cut off as per normal.
+
+Allow2ban state is stored in a [configurable cache](#cache-store-configuration) (which defaults to `Rails.cache` if present).
+
+```ruby
+# Lockout IP addresses that are hammering your login page.
+# After 20 requests in 1 minute, block all requests from that IP for 1 hour.
+Rack::Attack.blocklist('allow2ban login scrapers') do |req|
+  # `filter` returns false value if request is to your login page (but still
+  # increments the count) so request below the limit are not blocked until
+  # they hit the limit.  At that point, filter will return true and block.
+  Rack::Attack::Allow2Ban.filter(req.ip, maxretry: 20, findtime: 1.minute, bantime: 1.hour) do
+    # The count for the IP is incremented if the return value is truthy.
+    req.path == '/login' and req.post?
+  end
+end
+```
+
+### Throttling
+
+Throttle state is stored in a [configurable cache](#cache-store-configuration) (which defaults to `Rails.cache` if present).
+
+#### `throttle(name, options, &block)`
+
+Name your custom throttle, provide `limit` and `period` as options, and make your ruby-block argument return the __discriminator__. This discriminator is how you tell rack-attack whether you're limiting per IP address, per user email or any other.
+
+The request object is a [Rack::Request](http://www.rubydoc.info/gems/rack/Rack/Request).
+
+E.g.
+
+```ruby
+# config/initializers/rack_attack.rb (for rails apps)
+
+Rack::Attack.throttle("requests by ip", limit: 5, period: 2) do |request|
+  request.ip
+end
+
+# Throttle login attempts for a given email parameter to 6 reqs/minute
+# Return the email as a discriminator on POST /login requests
+Rack::Attack.throttle('limit logins per email', limit: 6, period: 60) do |req|
+  if req.path == '/login' && req.post?
+    req.params['email']
+  end
+end
+
+# You can also set a limit and period using a proc. For instance, after
+# Rack::Auth::Basic has authenticated the user:
+limit_proc = proc { |req| req.env["REMOTE_USER"] == "admin" ? 100 : 1 }
+period_proc = proc { |req| req.env["REMOTE_USER"] == "admin" ? 1 : 60 }
+
+Rack::Attack.throttle('request per ip', limit: limit_proc, period: period_proc) do |request|
+  request.ip
+end
+```
+
+### Tracks
+
+```ruby
+# Track requests from a special user agent.
+Rack::Attack.track("special_agent") do |req|
+  req.user_agent == "SpecialAgent"
+end
+
+# Supports optional limit and period, triggers the notification only when the limit is reached.
+Rack::Attack.track("special_agent", limit: 6, period: 60) do |req|
+  req.user_agent == "SpecialAgent"
+end
+
+# Track it using ActiveSupport::Notification
+ActiveSupport::Notifications.subscribe("rack.attack") do |name, start, finish, request_id, payload|
+  req = payload[:request]
+  if req.env['rack.attack.matched'] == "special_agent" && req.env['rack.attack.match_type'] == :track
+    Rails.logger.info "special_agent: #{req.path}"
+    STATSD.increment("special_agent")
+  end
+end
+```
+
+### Cache store configuration
+
+Throttle, allow2ban and fail2ban state is stored in a configurable cache (which defaults to `Rails.cache` if present), presumably backed by memcached or redis ([at least gem v3.0.0](https://rubygems.org/gems/redis)).
 
 ```ruby
 Rack::Attack.cache.store = ActiveSupport::Cache::MemoryStore.new # defaults to Rails.cache
 ```
 
-Note that `Rack::Attack.cache` is only used for throttling and fail2ban filtering; not blocklisting & safelisting. Your cache store must implement `increment` and `write` like [ActiveSupport::Cache::Store](http://api.rubyonrails.org/classes/ActiveSupport/Cache/Store.html).
+Note that `Rack::Attack.cache` is only used for throttling, allow2ban and fail2ban filtering; not blocklisting and safelisting. Your cache store must implement `increment` and `write` like [ActiveSupport::Cache::Store](http://api.rubyonrails.org/classes/ActiveSupport/Cache/Store.html).
+
+## Customizing responses
+
+Customize the response of blocklisted and throttled requests using an object that adheres to the [Rack app interface](http://www.rubydoc.info/github/rack/rack/file/SPEC).
+
+```ruby
+Rack::Attack.blocklisted_response = lambda do |env|
+  # Using 503 because it may make attacker think that they have successfully
+  # DOSed the site. Rack::Attack returns 403 for blocklists by default
+  [ 503, {}, ['Blocked']]
+end
+
+Rack::Attack.throttled_response = lambda do |env|
+  # NB: you have access to the name and other data about the matched throttle
+  #  env['rack.attack.matched'],
+  #  env['rack.attack.match_type'],
+  #  env['rack.attack.match_data'],
+  #  env['rack.attack.match_discriminator']
+
+  # Using 503 because it may make attacker think that they have successfully
+  # DOSed the site. Rack::Attack returns 429 for throttling by default
+  [ 503, {}, ["Server Error\n"]]
+end
+```
+
+### X-RateLimit headers for well-behaved clients
+
+While Rack::Attack's primary focus is minimizing harm from abusive clients, it
+can also be used to return rate limit data that's helpful for well-behaved clients.
+
+Here's an example response that includes conventional `X-RateLimit-*` headers:
+
+```ruby
+Rack::Attack.throttled_response = lambda do |env|
+  match_data = env['rack.attack.match_data']
+  now = match_data[:epoch_time]
+
+  headers = {
+    'X-RateLimit-Limit' => match_data[:limit].to_s,
+    'X-RateLimit-Remaining' => '0',
+    'X-RateLimit-Reset' => (now + (match_data[:period] - now % match_data[:period])).to_s
+  }
+
+  [ 429, headers, ["Throttled\n"]]
+end
+```
+
+
+For responses that did not exceed a throttle limit, Rack::Attack annotates the env with match data:
+
+```ruby
+request.env['rack.attack.throttle_data'][name] # => { :count => n, :period => p, :limit => l, :epoch_time => t }
+```
+
+## Logging & Instrumentation
+
+Rack::Attack uses the [ActiveSupport::Notifications](http://api.rubyonrails.org/classes/ActiveSupport/Notifications.html) API if available.
+
+You can subscribe to 'rack.attack' events and log it, graph it, etc:
+
+```ruby
+ActiveSupport::Notifications.subscribe('rack.attack') do |name, start, finish, request_id, payload|
+  puts payload[:request].inspect
+end
+```
 
 ## How it works
 
@@ -91,200 +368,10 @@ Note: `Rack::Attack::Request` is just a subclass of `Rack::Request` so that you
 can cleanly monkey patch helper methods onto the
 [request object](https://github.com/kickstarter/rack-attack/blob/master/lib/rack/attack/request.rb).
 
-## About Tracks
+### About Tracks
 
 `Rack::Attack.track` doesn't affect request processing. Tracks are an easy way to log and measure requests matching arbitrary attributes.
 
-## Usage
-
-Define safelists, blocklists, throttles, and tracks as blocks that return truthy values if matched, falsy otherwise. In a Rails app
-these go in an initializer in `config/initializers/`.
-A [Rack::Request](http://www.rubydoc.info/gems/rack/Rack/Request) object is passed to the block (named 'req' in the examples).
-
-### Safelists
-
-```ruby
-# Always allow requests from localhost
-# (blocklist & throttles are skipped)
-Rack::Attack.safelist('allow from localhost') do |req|
-  # Requests are allowed if the return value is truthy
-  '127.0.0.1' == req.ip || '::1' == req.ip
-end
-```
-
-### Blocklists
-
-```ruby
-# Block requests from 1.2.3.4
-Rack::Attack.blocklist('block 1.2.3.4') do |req|
-  # Requests are blocked if the return value is truthy
-  '1.2.3.4' == req.ip
-end
-
-# Block logins from a bad user agent
-Rack::Attack.blocklist('block bad UA logins') do |req|
-  req.path == '/login' && req.post? && req.user_agent == 'BadUA'
-end
-```
-
-#### Fail2Ban
-
-`Fail2Ban.filter` can be used within a blocklist to block all requests from misbehaving clients.
-This pattern is inspired by [fail2ban](http://www.fail2ban.org/wiki/index.php/Main_Page).
-See the [fail2ban documentation](http://www.fail2ban.org/wiki/index.php/MANUAL_0_8#Jail_Options) for more details on
-how the parameters work.  For multiple filters, be sure to put each filter in a separate blocklist and use a unique discriminator for each fail2ban filter.
-
-```ruby
-# Block suspicious requests for '/etc/password' or wordpress specific paths.
-# After 3 blocked requests in 10 minutes, block all requests from that IP for 5 minutes.
-Rack::Attack.blocklist('fail2ban pentesters') do |req|
-  # `filter` returns truthy value if request fails, or if it's from a previously banned IP
-  # so the request is blocked
-  Rack::Attack::Fail2Ban.filter("pentesters-#{req.ip}", maxretry: 3, findtime: 10.minutes, bantime: 5.minutes) do
-    # The count for the IP is incremented if the return value is truthy
-    CGI.unescape(req.query_string) =~ %r{/etc/passwd} ||
-    req.path.include?('/etc/passwd') ||
-    req.path.include?('wp-admin') ||
-    req.path.include?('wp-login')
-
-  end
-end
-```
-
-Note that `Fail2Ban` filters are not automatically scoped to the blocklist, so when using multiple filters in an application the scoping must be added to the discriminator e.g. `"pentest:#{req.ip}"`.
-
-#### Allow2Ban
-`Allow2Ban.filter` works the same way as the `Fail2Ban.filter` except that it *allows* requests from misbehaving
-clients until such time as they reach maxretry at which they are cut off as per normal.
-```ruby
-# Lockout IP addresses that are hammering your login page.
-# After 20 requests in 1 minute, block all requests from that IP for 1 hour.
-Rack::Attack.blocklist('allow2ban login scrapers') do |req|
-  # `filter` returns false value if request is to your login page (but still
-  # increments the count) so request below the limit are not blocked until
-  # they hit the limit.  At that point, filter will return true and block.
-  Rack::Attack::Allow2Ban.filter(req.ip, maxretry: 20, findtime: 1.minute, bantime: 1.hour) do
-    # The count for the IP is incremented if the return value is truthy.
-    req.path == '/login' and req.post?
-  end
-end
-```
-
-
-### Throttles
-
-```ruby
-# Throttle requests to 5 requests per second per ip
-Rack::Attack.throttle('req/ip', limit: 5, period: 1.second) do |req|
-  # If the return value is truthy, the cache key for the return value
-  # is incremented and compared with the limit. In this case:
-  #   "rack::attack:#{Time.now.to_i/1.second}:req/ip:#{req.ip}"
-  #
-  # If falsy, the cache key is neither incremented nor checked.
-
-  req.ip
-end
-
-# Throttle login attempts for a given email parameter to 6 reqs/minute
-# Return the email as a discriminator on POST /login requests
-Rack::Attack.throttle('logins/email', limit: 6, period: 60) do |req|
-  req.params['email'] if req.path == '/login' && req.post?
-end
-
-# You can also set a limit and period using a proc. For instance, after
-# Rack::Auth::Basic has authenticated the user:
-limit_proc = proc {|req| req.env["REMOTE_USER"] == "admin" ? 100 : 1}
-period_proc = proc {|req| req.env["REMOTE_USER"] == "admin" ? 1.second : 1.minute}
-Rack::Attack.throttle('req/ip', limit: limit_proc, period: period_proc) do |req|
-  req.ip
-end
-```
-
-### Tracks
-
-```ruby
-# Track requests from a special user agent.
-Rack::Attack.track("special_agent") do |req|
-  req.user_agent == "SpecialAgent"
-end
-
-# Supports optional limit and period, triggers the notification only when the limit is reached.
-Rack::Attack.track("special_agent", limit: 6, period: 60) do |req|
-  req.user_agent == "SpecialAgent"
-end
-
-# Track it using ActiveSupport::Notification
-ActiveSupport::Notifications.subscribe("rack.attack") do |name, start, finish, request_id, req|
-  if req.env['rack.attack.matched'] == "special_agent" && req.env['rack.attack.match_type'] == :track
-    Rails.logger.info "special_agent: #{req.path}"
-    STATSD.increment("special_agent")
-  end
-end
-```
-
-## Responses
-
-Customize the response of blocklisted and throttled requests using an object that adheres to the [Rack app interface](http://rack.rubyforge.org/doc/SPEC.html).
-
-```ruby
-Rack::Attack.blocklisted_response = lambda do |env|
-  # Using 503 because it may make attacker think that they have successfully
-  # DOSed the site. Rack::Attack returns 403 for blocklists by default
-  [ 503, {}, ['Blocked']]
-end
-
-Rack::Attack.throttled_response = lambda do |env|
-  # NB: you have access to the name and other data about the matched throttle
-  #  env['rack.attack.matched'],
-  #  env['rack.attack.match_type'],
-  #  env['rack.attack.match_data']
-
-  # Using 503 because it may make attacker think that they have successfully
-  # DOSed the site. Rack::Attack returns 429 for throttling by default
-  [ 503, {}, ["Server Error\n"]]
-end
-```
-
-### X-RateLimit headers for well-behaved clients
-
-While Rack::Attack's primary focus is minimizing harm from abusive clients, it
-can also be used to return rate limit data that's helpful for well-behaved clients.
-
-Here's an example response that includes conventional `X-RateLimit-*` headers:
-
-```ruby
-Rack::Attack.throttled_response = lambda do |env|
-  now = Time.now
-  match_data = env['rack.attack.match_data']
-
-  headers = {
-    'X-RateLimit-Limit' => match_data[:limit].to_s,
-    'X-RateLimit-Remaining' => '0',
-    'X-RateLimit-Reset' => (now + (match_data[:period] - now.to_i % match_data[:period])).to_s
-  }
-
-  [ 429, headers, ["Throttled\n"]]
-end
-```
-
-
-For responses that did not exceed a throttle limit, Rack::Attack annotates the env with match data:
-
-```ruby
-request.env['rack.attack.throttle_data'][name] # => { :count => n, :period => p, :limit => l }
-```
-
-## Logging & Instrumentation
-
-Rack::Attack uses the [ActiveSupport::Notifications](http://api.rubyonrails.org/classes/ActiveSupport/Notifications.html) API if available.
-
-You can subscribe to 'rack.attack' events and log it, graph it, etc:
-
-```ruby
-ActiveSupport::Notifications.subscribe('rack.attack') do |name, start, finish, request_id, req|
-  puts req.inspect
-end
-```
 
 ## Testing
 
@@ -302,7 +389,7 @@ so try to keep the number of throttle checks per request low.
 If a request is blocklisted or throttled, the response is a very simple Rack response.
 A single typical ruby web server thread can block several hundred requests per second.
 
-Rack::Attack complements tools like `iptables` and nginx's [limit_conn_zone module](http://nginx.org/en/docs/http/ngx_http_limit_conn_module.html#limit_conn_zone).
+Rack::Attack complements tools like `iptables` and nginx's [limit_conn_zone module](https://nginx.org/en/docs/http/ngx_http_limit_conn_module.html#limit_conn_zone).
 
 ## Motivation
 
@@ -316,26 +403,15 @@ less on short-term, one-off hacks to block a particular attack.
 
 ## Contributing
 
-Pull requests and issues are greatly appreciated. This project is intended to be
-a safe, welcoming space for collaboration, and contributors are expected to
-adhere to the [Code of Conduct](CODE_OF_CONDUCT.md).
+Check out the [Contributing guide](CONTRIBUTING.md).
 
-### Testing pull requests
+## Code of Conduct
 
-To run the minitest test suite, you will need both [Redis](http://redis.io/) and
-[Memcached](https://memcached.org/) running locally and bound to IP `127.0.0.1` on
-default ports (`6379` for Redis, and `11211` for Memcached) and able to be
-accessed without authentication.
+This project is intended to be a safe, welcoming space for collaboration, and contributors are expected to adhere to the [Code of Conduct](CODE_OF_CONDUCT.md).
 
-Install dependencies by running
-```sh
-bundle install
-```
+## Development setup
 
-Then run the test suite by running
-```sh
-bundle exec rake
-```
+Check out the [Development guide](docs/development.md).
 
 ## Mailing list
 
@@ -348,4 +424,4 @@ New releases of Rack::Attack are announced on
 
 Copyright Kickstarter, PBC.
 
-Released under an [MIT License](http://opensource.org/licenses/MIT).
+Released under an [MIT License](https://opensource.org/licenses/MIT).
diff --git a/Rakefile b/Rakefile
index 300ec21..f08b537 100644
--- a/Rakefile
+++ b/Rakefile
@@ -1,7 +1,12 @@
+# frozen_string_literal: true
+
 require "rubygems"
 require "bundler/setup"
 require 'bundler/gem_tasks'
 require 'rake/testtask'
+require "rubocop/rake_task"
+
+RuboCop::RakeTask.new
 
 namespace :test do
   Rake::TestTask.new(:units) do |t|
@@ -11,9 +16,14 @@ namespace :test do
   Rake::TestTask.new(:integration) do |t|
     t.pattern = "spec/integration/*_spec.rb"
   end
+
+  Rake::TestTask.new(:acceptance) do |t|
+    t.pattern = "spec/acceptance/**/*_spec.rb"
+  end
 end
 
-desc 'Run tests'
-task :test => %w[test:units test:integration]
+Rake::TestTask.new(:test) do |t|
+  t.pattern = "spec/**/*_spec.rb"
+end
 
-task :default => :test
+task :default => [:rubocop, :test]
diff --git a/docs/development.md b/docs/development.md
new file mode 100644
index 0000000..c3fec28
--- /dev/null
+++ b/docs/development.md
@@ -0,0 +1,13 @@
+# Rack::Attack: Development
+
+## Running the tests
+
+You will need both [Redis](https://redis.io/) and [Memcached](https://memcached.org/) running locally and bound to IP `127.0.0.1` on default ports (`6379` for Redis, and `11211` for Memcached) and able to be accessed without authentication.
+
+Install dependencies by running
+
+    $ bundle install
+
+Then run the test suite by running
+
+    $ bundle exec appraisal rake test
diff --git a/examples/rack_attack.rb b/examples/rack_attack.rb
index eea07c0..43f1348 100644
--- a/examples/rack_attack.rb
+++ b/examples/rack_attack.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 # NB: `req` is a Rack::Request object (basically an env hash with friendly accessor methods)
 
 # Throttle 10 requests/ip/second
diff --git a/gemfiles/active_support_redis_cache_store.gemfile b/gemfiles/active_support_redis_cache_store.gemfile
new file mode 100644
index 0000000..040271b
--- /dev/null
+++ b/gemfiles/active_support_redis_cache_store.gemfile
@@ -0,0 +1,10 @@
+# frozen_string_literal: true
+
+# This file was generated by Appraisal
+
+source "https://rubygems.org"
+
+gem "activesupport", "~> 5.2.0"
+gem "redis", "~> 4.0"
+
+gemspec path: "../"
diff --git a/gemfiles/active_support_redis_cache_store_pooled.gemfile b/gemfiles/active_support_redis_cache_store_pooled.gemfile
new file mode 100644
index 0000000..357ca42
--- /dev/null
+++ b/gemfiles/active_support_redis_cache_store_pooled.gemfile
@@ -0,0 +1,11 @@
+# frozen_string_literal: true
+
+# This file was generated by Appraisal
+
+source "https://rubygems.org"
+
+gem "activesupport", "~> 5.2.0"
+gem "connection_pool", "~> 2.2"
+gem "redis", "~> 4.0"
+
+gemspec path: "../"
diff --git a/gemfiles/active_support_redis_store.gemfile b/gemfiles/active_support_redis_store.gemfile
new file mode 100644
index 0000000..922f3cc
--- /dev/null
+++ b/gemfiles/active_support_redis_store.gemfile
@@ -0,0 +1,9 @@
+# frozen_string_literal: true
+
+# This file was generated by Appraisal
+
+source "https://rubygems.org"
+
+gem "redis-activesupport", "~> 5.0"
+
+gemspec path: "../"
diff --git a/gemfiles/connection_pool_dalli.gemfile b/gemfiles/connection_pool_dalli.gemfile
new file mode 100644
index 0000000..8c62b05
--- /dev/null
+++ b/gemfiles/connection_pool_dalli.gemfile
@@ -0,0 +1,10 @@
+# frozen_string_literal: true
+
+# This file was generated by Appraisal
+
+source "https://rubygems.org"
+
+gem "connection_pool", "~> 2.2"
+gem "dalli", "~> 2.7"
+
+gemspec path: "../"
diff --git a/gemfiles/dalli2.gemfile b/gemfiles/dalli2.gemfile
index f955198..1628ad6 100644
--- a/gemfiles/dalli2.gemfile
+++ b/gemfiles/dalli2.gemfile
@@ -1,13 +1,9 @@
+# frozen_string_literal: true
+
 # This file was generated by Appraisal
 
 source "https://rubygems.org"
 
 gem "dalli", "~> 2.0"
 
-group :development do
-  gem "pry"
-  gem "guard"
-  gem "guard-minitest"
-end
-
 gemspec path: "../"
diff --git a/gemfiles/rack_1_6.gemfile b/gemfiles/rack_1_6.gemfile
new file mode 100644
index 0000000..91789b4
--- /dev/null
+++ b/gemfiles/rack_1_6.gemfile
@@ -0,0 +1,12 @@
+# frozen_string_literal: true
+
+# This file was generated by Appraisal
+
+source "https://rubygems.org"
+
+gem "actionpack", ">= 4.2"
+gem "activesupport", ">= 4.2"
+gem "rack", "~> 1.6.9"
+gem "rack-test", ">= 0.6"
+
+gemspec path: "../"
diff --git a/gemfiles/rack_2_0.gemfile b/gemfiles/rack_2_0.gemfile
new file mode 100644
index 0000000..c7866b6
--- /dev/null
+++ b/gemfiles/rack_2_0.gemfile
@@ -0,0 +1,9 @@
+# frozen_string_literal: true
+
+# This file was generated by Appraisal
+
+source "https://rubygems.org"
+
+gem "rack", "~> 2.0.4"
+
+gemspec path: "../"
diff --git a/gemfiles/rails_4_2.gemfile b/gemfiles/rails_4_2.gemfile
index d4532c5..5e7dfe3 100644
--- a/gemfiles/rails_4_2.gemfile
+++ b/gemfiles/rails_4_2.gemfile
@@ -1,14 +1,11 @@
+# frozen_string_literal: true
+
 # This file was generated by Appraisal
 
 source "https://rubygems.org"
 
-gem "activesupport", "~> 4.2.0"
 gem "actionpack", "~> 4.2.0"
-
-group :development do
-  gem "pry"
-  gem "guard"
-  gem "guard-minitest"
-end
+gem "activesupport", "~> 4.2.0"
+gem "rack-test", ">= 0.6"
 
 gemspec path: "../"
diff --git a/gemfiles/rails_5_0.gemfile b/gemfiles/rails_5_0.gemfile
deleted file mode 100644
index 0fea132..0000000
--- a/gemfiles/rails_5_0.gemfile
+++ /dev/null
@@ -1,14 +0,0 @@
-# This file was generated by Appraisal
-
-source "https://rubygems.org"
-
-gem "activesupport", "~> 5.0.0"
-gem "actionpack", "~> 5.0.0"
-
-group :development do
-  gem "pry"
-  gem "guard"
-  gem "guard-minitest"
-end
-
-gemspec path: "../"
diff --git a/gemfiles/rails_5_1.gemfile b/gemfiles/rails_5_1.gemfile
index bb501ef..bac5d16 100644
--- a/gemfiles/rails_5_1.gemfile
+++ b/gemfiles/rails_5_1.gemfile
@@ -1,14 +1,10 @@
+# frozen_string_literal: true
+
 # This file was generated by Appraisal
 
 source "https://rubygems.org"
 
-gem "activesupport", "~> 5.1.0"
 gem "actionpack", "~> 5.1.0"
-
-group :development do
-  gem "pry"
-  gem "guard"
-  gem "guard-minitest"
-end
+gem "activesupport", "~> 5.1.0"
 
 gemspec path: "../"
diff --git a/gemfiles/rails_5_2.gemfile b/gemfiles/rails_5_2.gemfile
new file mode 100644
index 0000000..1873512
--- /dev/null
+++ b/gemfiles/rails_5_2.gemfile
@@ -0,0 +1,10 @@
+# frozen_string_literal: true
+
+# This file was generated by Appraisal
+
+source "https://rubygems.org"
+
+gem "actionpack", "~> 5.2.0"
+gem "activesupport", "~> 5.2.0"
+
+gemspec path: "../"
diff --git a/gemfiles/redis_store.gemfile b/gemfiles/redis_store.gemfile
new file mode 100644
index 0000000..0ba921a
--- /dev/null
+++ b/gemfiles/redis_store.gemfile
@@ -0,0 +1,9 @@
+# frozen_string_literal: true
+
+# This file was generated by Appraisal
+
+source "https://rubygems.org"
+
+gem "redis-store", "~> 1.5"
+
+gemspec path: "../"
diff --git a/lib/rack/attack.rb b/lib/rack/attack.rb
index 346fbe5..f59e155 100644
--- a/lib/rack/attack.rb
+++ b/lib/rack/attack.rb
@@ -1,43 +1,51 @@
+# frozen_string_literal: true
+
 require 'rack'
 require 'forwardable'
+require 'rack/attack/path_normalizer'
+require 'rack/attack/request'
+require "ipaddr"
 
 class Rack::Attack
-  autoload :Cache,           'rack/attack/cache'
-  autoload :PathNormalizer,  'rack/attack/path_normalizer'
-  autoload :Check,           'rack/attack/check'
-  autoload :Throttle,        'rack/attack/throttle'
-  autoload :Safelist,        'rack/attack/safelist'
-  autoload :Blocklist,       'rack/attack/blocklist'
-  autoload :Track,           'rack/attack/track'
-  autoload :StoreProxy,      'rack/attack/store_proxy'
-  autoload :DalliProxy,      'rack/attack/store_proxy/dalli_proxy'
-  autoload :MemCacheProxy,   'rack/attack/store_proxy/mem_cache_proxy'
-  autoload :RedisStoreProxy, 'rack/attack/store_proxy/redis_store_proxy'
-  autoload :RedisProxy,      'rack/attack/store_proxy/redis_proxy'
-  autoload :Fail2Ban,        'rack/attack/fail2ban'
-  autoload :Allow2Ban,       'rack/attack/allow2ban'
-  autoload :Request,         'rack/attack/request'
+  class MisconfiguredStoreError < StandardError; end
+  class MissingStoreError < StandardError; end
+
+  autoload :Cache,                'rack/attack/cache'
+  autoload :Check,                'rack/attack/check'
+  autoload :Throttle,             'rack/attack/throttle'
+  autoload :Safelist,             'rack/attack/safelist'
+  autoload :Blocklist,            'rack/attack/blocklist'
+  autoload :Track,                'rack/attack/track'
+  autoload :StoreProxy,           'rack/attack/store_proxy'
+  autoload :DalliProxy,           'rack/attack/store_proxy/dalli_proxy'
+  autoload :MemCacheProxy,        'rack/attack/store_proxy/mem_cache_proxy'
+  autoload :RedisProxy,           'rack/attack/store_proxy/redis_proxy'
+  autoload :RedisStoreProxy,      'rack/attack/store_proxy/redis_store_proxy'
+  autoload :RedisCacheStoreProxy, 'rack/attack/store_proxy/redis_cache_store_proxy'
+  autoload :Fail2Ban,             'rack/attack/fail2ban'
+  autoload :Allow2Ban,            'rack/attack/allow2ban'
 
   class << self
-
     attr_accessor :notifier, :blocklisted_response, :throttled_response
 
     def safelist(name, &block)
       self.safelists[name] = Safelist.new(name, block)
     end
 
-    def whitelist(name, &block)
-      warn "[DEPRECATION] 'Rack::Attack.whitelist' is deprecated.  Please use 'safelist' instead."
-      safelist(name, &block)
-    end
-
     def blocklist(name, &block)
       self.blocklists[name] = Blocklist.new(name, block)
     end
 
-    def blacklist(name, &block)
-      warn "[DEPRECATION] 'Rack::Attack.blacklist' is deprecated.  Please use 'blocklist' instead."
-      blocklist(name, &block)
+    def blocklist_ip(ip_address)
+      @ip_blocklists ||= []
+      ip_blocklist_proc = lambda { |request| IPAddr.new(ip_address).include?(IPAddr.new(request.ip)) }
+      @ip_blocklists << Blocklist.new(nil, ip_blocklist_proc)
+    end
+
+    def safelist_ip(ip_address)
+      @ip_safelists ||= []
+      ip_safelist_proc = lambda { |request| IPAddr.new(ip_address).include?(IPAddr.new(request.ip)) }
+      @ip_safelists << Safelist.new(nil, ip_safelist_proc)
     end
 
     def throttle(name, options, &block)
@@ -49,84 +57,71 @@ class Rack::Attack
     end
 
     def safelists;  @safelists  ||= {}; end
+
     def blocklists; @blocklists ||= {}; end
+
     def throttles;  @throttles  ||= {}; end
+
     def tracks;     @tracks     ||= {}; end
 
-    def whitelists
-      warn "[DEPRECATION] 'Rack::Attack.whitelists' is deprecated.  Please use 'safelists' instead."
-      safelists
+    def safelisted?(request)
+      ip_safelists.any? { |safelist| safelist.matched_by?(request) } ||
+        safelists.any? { |_name, safelist| safelist.matched_by?(request) }
     end
 
-    def blacklists
-      warn "[DEPRECATION] 'Rack::Attack.blacklists' is deprecated.  Please use 'blocklists' instead."
-      blocklists
+    def blocklisted?(request)
+      ip_blocklists.any? { |blocklist| blocklist.matched_by?(request) } ||
+        blocklists.any? { |_name, blocklist| blocklist.matched_by?(request) }
     end
 
-    def safelisted?(req)
-      safelists.any? do |name, safelist|
-        safelist[req]
+    def throttled?(request)
+      throttles.any? do |_name, throttle|
+        throttle.matched_by?(request)
       end
     end
 
-    def whitelisted?(req)
-      warn "[DEPRECATION] 'Rack::Attack.whitelisted?' is deprecated.  Please use 'safelisted?' instead."
-      safelisted?(req)
-    end
-
-    def blocklisted?(req)
-      blocklists.any? do |name, blocklist|
-        blocklist[req]
+    def tracked?(request)
+      tracks.each_value do |track|
+        track.matched_by?(request)
       end
     end
 
-    def blacklisted?(req)
-      warn "[DEPRECATION] 'Rack::Attack.blacklisted?' is deprecated.  Please use 'blocklisted?' instead."
-      blocklisted?(req)
-    end
-
-    def throttled?(req)
-      throttles.any? do |name, throttle|
-        throttle[req]
-      end
-    end
-
-    def tracked?(req)
-      tracks.each_value do |tracker|
-        tracker[req]
-      end
-    end
-
-    def instrument(req)
-      notifier.instrument('rack.attack', req) if notifier
+    def instrument(request)
+      notifier.instrument('rack.attack', request: request) if notifier
     end
 
     def cache
       @cache ||= Cache.new
     end
 
-    def clear!
+    def clear_configuration
       @safelists, @blocklists, @throttles, @tracks = {}, {}, {}, {}
+      @ip_blocklists = []
+      @ip_safelists = []
     end
 
-    def blacklisted_response=(res)
-      warn "[DEPRECATION] 'Rack::Attack.blacklisted_response=' is deprecated.  Please use 'blocklisted_response=' instead."
-      self.blocklisted_response=(res)
+    def clear!
+      warn "[DEPRECATION] Rack::Attack.clear! is deprecated. Please use Rack::Attack.clear_configuration instead"
+      clear_configuration
     end
 
-    def blacklisted_response
-      warn "[DEPRECATION] 'Rack::Attack.blacklisted_response' is deprecated.  Please use 'blocklisted_response' instead."
-      blocklisted_response
+    private
+
+    def ip_blocklists
+      @ip_blocklists ||= []
     end
 
+    def ip_safelists
+      @ip_safelists ||= []
+    end
   end
 
   # Set defaults
   @notifier             = ActiveSupport::Notifications if defined?(ActiveSupport::Notifications)
-  @blocklisted_response = lambda {|env| [403, {'Content-Type' => 'text/plain'}, ["Forbidden\n"]] }
-  @throttled_response   = lambda {|env|
+  @blocklisted_response = lambda { |_env| [403, { 'Content-Type' => 'text/plain' }, ["Forbidden\n"]] }
+  @throttled_response   = lambda { |env|
     retry_after = (env['rack.attack.match_data'] || {})[:period]
-    [429, {'Content-Type' => 'text/plain', 'Retry-After' => retry_after.to_s}, ["Retry later\n"]]
+    [429, { 'Content-Type' => 'text/plain', 'Retry-After' => retry_after.to_s }, ["Retry later\n"]]
   }
 
   def initialize(app)
@@ -135,23 +130,20 @@ class Rack::Attack
 
   def call(env)
     env['PATH_INFO'] = PathNormalizer.normalize_path(env['PATH_INFO'])
-    req = Rack::Attack::Request.new(env)
+    request = Rack::Attack::Request.new(env)
 
-    if safelisted?(req)
+    if safelisted?(request)
       @app.call(env)
-    elsif blocklisted?(req)
+    elsif blocklisted?(request)
       self.class.blocklisted_response.call(env)
-    elsif throttled?(req)
+    elsif throttled?(request)
       self.class.throttled_response.call(env)
     else
-      tracked?(req)
+      tracked?(request)
       @app.call(env)
     end
   end
 
   extend Forwardable
-  def_delegators self, :safelisted?,
-                       :blocklisted?,
-                       :throttled?,
-                       :tracked?
+  def_delegators self, :safelisted?, :blocklisted?, :throttled?, :tracked?
 end
diff --git a/lib/rack/attack/allow2ban.rb b/lib/rack/attack/allow2ban.rb
index 763253b..faa3518 100644
--- a/lib/rack/attack/allow2ban.rb
+++ b/lib/rack/attack/allow2ban.rb
@@ -1,8 +1,11 @@
+# frozen_string_literal: true
+
 module Rack
   class Attack
     class Allow2Ban < Fail2Ban
       class << self
         protected
+
         def key_prefix
           'allow2ban'
         end
diff --git a/lib/rack/attack/blocklist.rb b/lib/rack/attack/blocklist.rb
index b61a29f..ee57656 100644
--- a/lib/rack/attack/blocklist.rb
+++ b/lib/rack/attack/blocklist.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Rack
   class Attack
     class Blocklist < Check
@@ -5,7 +7,6 @@ module Rack
         super
         @type = :blocklist
       end
-
     end
   end
 end
diff --git a/lib/rack/attack/cache.rb b/lib/rack/attack/cache.rb
index c2dd06c..1c8030e 100644
--- a/lib/rack/attack/cache.rb
+++ b/lib/rack/attack/cache.rb
@@ -1,8 +1,10 @@
+# frozen_string_literal: true
+
 module Rack
   class Attack
     class Cache
-
       attr_accessor :prefix
+      attr_reader :last_epoch_time
 
       def initialize
         self.store = ::Rails.cache if defined?(::Rails.cache)
@@ -20,6 +22,9 @@ module Rack
       end
 
       def read(unprefixed_key)
+        enforce_store_presence!
+        enforce_store_method_presence!(:read)
+
         store.read("#{prefix}:#{unprefixed_key}")
       end
 
@@ -39,22 +44,38 @@ module Rack
       private
 
       def key_and_expiry(unprefixed_key, period)
-        epoch_time = Time.now.to_i
-        # Add 1 to expires_in to avoid timing error: http://git.io/i1PHXA
-        expires_in = (period - (epoch_time % period) + 1).to_i
-        ["#{prefix}:#{(epoch_time / period).to_i}:#{unprefixed_key}", expires_in]
+        @last_epoch_time = Time.now.to_i
+        # Add 1 to expires_in to avoid timing error: https://git.io/i1PHXA
+        expires_in = (period - (@last_epoch_time % period) + 1).to_i
+        ["#{prefix}:#{(@last_epoch_time / period).to_i}:#{unprefixed_key}", expires_in]
       end
 
       def do_count(key, expires_in)
+        enforce_store_presence!
+        enforce_store_method_presence!(:increment)
+
         result = store.increment(key, 1, :expires_in => expires_in)
 
         # NB: Some stores return nil when incrementing uninitialized values
         if result.nil?
+          enforce_store_method_presence!(:write)
+
           store.write(key, 1, :expires_in => expires_in)
         end
         result || 1
       end
 
+      def enforce_store_presence!
+        if store.nil?
+          raise Rack::Attack::MissingStoreError
+        end
+      end
+
+      def enforce_store_method_presence!(method_name)
+        if !store.respond_to?(method_name)
+          raise Rack::Attack::MisconfiguredStoreError, "Store needs to respond to ##{method_name}"
+        end
+      end
     end
   end
 end
diff --git a/lib/rack/attack/check.rb b/lib/rack/attack/check.rb
index 21451de..2e5c64d 100644
--- a/lib/rack/attack/check.rb
+++ b/lib/rack/attack/check.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Rack
   class Attack
     class Check
@@ -7,17 +9,15 @@ module Rack
         @type = options.fetch(:type, nil)
       end
 
-      def [](req)
-        block[req].tap {|match|
+      def matched_by?(request)
+        block.call(request).tap do |match|
           if match
-            req.env["rack.attack.matched"] = name
-            req.env["rack.attack.match_type"] = type
-            Rack::Attack.instrument(req)
+            request.env["rack.attack.matched"] = name
+            request.env["rack.attack.match_type"] = type
+            Rack::Attack.instrument(request)
           end
-        }
+        end
       end
-
     end
   end
 end
-
diff --git a/lib/rack/attack/fail2ban.rb b/lib/rack/attack/fail2ban.rb
index 76dc59f..b43c7cb 100644
--- a/lib/rack/attack/fail2ban.rb
+++ b/lib/rack/attack/fail2ban.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Rack
   class Attack
     class Fail2Ban
@@ -27,6 +29,7 @@ module Rack
         end
 
         protected
+
         def key_prefix
           'fail2ban'
         end
@@ -40,8 +43,8 @@ module Rack
           true
         end
 
-
         private
+
         def ban!(discriminator, bantime)
           cache.write("#{key_prefix}:ban:#{discriminator}", 1, bantime)
         end
diff --git a/lib/rack/attack/path_normalizer.rb b/lib/rack/attack/path_normalizer.rb
index 4b4171e..635f9f2 100644
--- a/lib/rack/attack/path_normalizer.rb
+++ b/lib/rack/attack/path_normalizer.rb
@@ -1,8 +1,9 @@
-class Rack::Attack
+# frozen_string_literal: true
 
+class Rack::Attack
   # When using Rack::Attack with a Rails app, developers expect the request path
   # to be normalized. In particular, trailing slashes are stripped.
-  # (See http://git.io/v0rrR for implementation.)
+  # (See https://git.io/v0rrR for implementation.)
   #
   # Look for an ActionDispatch utility class that Rails folks would expect
   # to normalize request paths. If unavailable, use a fallback class that
@@ -15,10 +16,9 @@ class Rack::Attack
   end
 
   PathNormalizer = if defined?(::ActionDispatch::Journey::Router::Utils)
-                 # For Rails apps
-                 ::ActionDispatch::Journey::Router::Utils
-               else
-                 FallbackPathNormalizer
-               end
-
+                     # For Rails apps
+                     ::ActionDispatch::Journey::Router::Utils
+                   else
+                     FallbackPathNormalizer
+                   end
 end
diff --git a/lib/rack/attack/request.rb b/lib/rack/attack/request.rb
index ee05f89..1cac479 100644
--- a/lib/rack/attack/request.rb
+++ b/lib/rack/attack/request.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 # Rack::Attack::Request is the same as ::Rack::Request by default.
 #
 # This is a safe place to add custom helper methods to the request object
diff --git a/lib/rack/attack/safelist.rb b/lib/rack/attack/safelist.rb
index 748d422..d335be2 100644
--- a/lib/rack/attack/safelist.rb
+++ b/lib/rack/attack/safelist.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Rack
   class Attack
     class Safelist < Check
@@ -5,7 +7,6 @@ module Rack
         super
         @type = :safelist
       end
-
     end
   end
 end
diff --git a/lib/rack/attack/store_proxy.rb b/lib/rack/attack/store_proxy.rb
index d41ddac..2754467 100644
--- a/lib/rack/attack/store_proxy.rb
+++ b/lib/rack/attack/store_proxy.rb
@@ -1,10 +1,12 @@
+# frozen_string_literal: true
+
 module Rack
   class Attack
     module StoreProxy
-      PROXIES = [DalliProxy, MemCacheProxy, RedisStoreProxy, RedisProxy].freeze
+      PROXIES = [DalliProxy, MemCacheProxy, RedisProxy, RedisStoreProxy, RedisCacheStoreProxy].freeze
 
-      ACTIVE_SUPPORT_WRAPPER_CLASSES = Set.new(['ActiveSupport::Cache::MemCacheStore', 'ActiveSupport::Cache::RedisStore']).freeze
-      ACTIVE_SUPPORT_CLIENTS = Set.new(['Redis::Store', 'Redis', 'Dalli::Client', 'MemCache']).freeze
+      ACTIVE_SUPPORT_WRAPPER_CLASSES = Set.new(['ActiveSupport::Cache::MemCacheStore', 'ActiveSupport::Cache::RedisStore', 'ActiveSupport::Cache::RedisCacheStore']).freeze
+      ACTIVE_SUPPORT_CLIENTS = Set.new(['Redis::Store', 'Dalli::Client', 'MemCache']).freeze
 
       def self.build(store)
         client = unwrap_active_support_stores(store)
@@ -12,8 +14,6 @@ module Rack
         klass ? klass.new(client) : client
       end
 
-
-      private
       def self.unwrap_active_support_stores(store)
         # ActiveSupport::Cache::RedisStore doesn't expose any way to set an expiry,
         # so use the raw Redis::Store instead.
diff --git a/lib/rack/attack/store_proxy/dalli_proxy.rb b/lib/rack/attack/store_proxy/dalli_proxy.rb
index 703f2d6..f3fbc6c 100644
--- a/lib/rack/attack/store_proxy/dalli_proxy.rb
+++ b/lib/rack/attack/store_proxy/dalli_proxy.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require 'delegate'
 
 module Rack
@@ -28,14 +30,14 @@ module Rack
         rescue Dalli::DalliError
         end
 
-        def write(key, value, options={})
+        def write(key, value, options = {})
           with do |client|
             client.set(key, value, options.fetch(:expires_in, 0), raw: true)
           end
         rescue Dalli::DalliError
         end
 
-        def increment(key, amount, options={})
+        def increment(key, amount, options = {})
           with do |client|
             client.incr(key, amount, options.fetch(:expires_in, 0), amount)
           end
@@ -58,7 +60,6 @@ module Rack
             end
           end
         end
-
       end
     end
   end
diff --git a/lib/rack/attack/store_proxy/mem_cache_proxy.rb b/lib/rack/attack/store_proxy/mem_cache_proxy.rb
index 098e048..8ed6583 100644
--- a/lib/rack/attack/store_proxy/mem_cache_proxy.rb
+++ b/lib/rack/attack/store_proxy/mem_cache_proxy.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Rack
   class Attack
     module StoreProxy
@@ -14,21 +16,21 @@ module Rack
         def read(key)
           # Second argument: reading raw value
           get(key, true)
-          rescue MemCache::MemCacheError
+        rescue MemCache::MemCacheError
         end
 
-        def write(key, value, options={})
+        def write(key, value, options = {})
           # Third argument: writing raw value
           set(key, value, options.fetch(:expires_in, 0), true)
         rescue MemCache::MemCacheError
         end
 
-        def increment(key, amount, options={})
+        def increment(key, amount, _options = {})
           incr(key, amount)
         rescue MemCache::MemCacheError
         end
 
-        def delete(key, options={})
+        def delete(key, _options = {})
           with do |client|
             client.delete(key)
           end
@@ -44,7 +46,6 @@ module Rack
             end
           end
         end
-
       end
     end
   end
diff --git a/lib/rack/attack/store_proxy/redis_cache_store_proxy.rb b/lib/rack/attack/store_proxy/redis_cache_store_proxy.rb
new file mode 100644
index 0000000..c7feaa7
--- /dev/null
+++ b/lib/rack/attack/store_proxy/redis_cache_store_proxy.rb
@@ -0,0 +1,37 @@
+# frozen_string_literal: true
+
+require 'delegate'
+
+module Rack
+  class Attack
+    module StoreProxy
+      class RedisCacheStoreProxy < SimpleDelegator
+        def self.handle?(store)
+          defined?(::Redis) && defined?(::ActiveSupport::Cache::RedisCacheStore) && store.is_a?(::ActiveSupport::Cache::RedisCacheStore)
+        end
+
+        def increment(name, amount = 1, options = {})
+          # RedisCacheStore#increment ignores options[:expires_in].
+          #
+          # So in order to workaround this we use RedisCacheStore#write (which sets expiration) to initialize
+          # the counter. After that we continue using the original RedisCacheStore#increment.
+          if options[:expires_in] && !read(name)
+            write(name, amount, options)
+
+            amount
+          else
+            super
+          end
+        end
+
+        def read(name, options = {})
+          super(name, options.merge!(raw: true))
+        end
+
+        def write(name, value, options = {})
+          super(name, value, options.merge!(raw: true))
+        end
+      end
+    end
+  end
+end
diff --git a/lib/rack/attack/store_proxy/redis_store_proxy.rb b/lib/rack/attack/store_proxy/redis_store_proxy.rb
index c980369..a7ac81a 100644
--- a/lib/rack/attack/store_proxy/redis_store_proxy.rb
+++ b/lib/rack/attack/store_proxy/redis_store_proxy.rb
@@ -1,15 +1,21 @@
+# frozen_string_literal: true
+
 require 'delegate'
 
 module Rack
   class Attack
     module StoreProxy
       class RedisStoreProxy < SimpleDelegator
-        def self.handle?(store)
-          defined?(::Redis::Store) && store.is_a?(::Redis::Store)
+        def initialize(*args)
+          if Gem::Version.new(Redis::VERSION) < Gem::Version.new("3")
+            warn 'RackAttack requires Redis gem >= 3.0.0.'
+          end
+
+          super(*args)
         end
 
-        def initialize(store)
-          super(store)
+        def self.handle?(store)
+          defined?(::Redis::Store) && store.is_a?(::Redis::Store)
         end
 
         def read(key)
@@ -17,7 +23,7 @@ module Rack
         rescue Redis::BaseError
         end
 
-        def write(key, value, options={})
+        def write(key, value, options = {})
           if (expires_in = options[:expires_in])
             setex(key, expires_in, value, raw: true)
           else
@@ -26,7 +32,7 @@ module Rack
         rescue Redis::BaseError
         end
 
-        def increment(key, amount, options={})
+        def increment(key, amount, options = {})
           count = nil
 
           pipelined do
@@ -38,7 +44,7 @@ module Rack
         rescue Redis::BaseError
         end
 
-        def delete(key, options={})
+        def delete(key, _options = {})
           del(key)
         rescue Redis::BaseError
         end
diff --git a/lib/rack/attack/throttle.rb b/lib/rack/attack/throttle.rb
index 19a6519..e834fc0 100644
--- a/lib/rack/attack/throttle.rb
+++ b/lib/rack/attack/throttle.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Rack
   class Attack
     class Throttle
@@ -18,29 +20,32 @@ module Rack
         Rack::Attack.cache
       end
 
-      def [](req)
-        discriminator = block[req]
+      def matched_by?(request)
+        discriminator = block.call(request)
         return false unless discriminator
 
-        current_period = period.respond_to?(:call) ? period.call(req) : period
-        current_limit  = limit.respond_to?(:call) ? limit.call(req) : limit
+        current_period = period.respond_to?(:call) ? period.call(request) : period
+        current_limit  = limit.respond_to?(:call) ? limit.call(request) : limit
         key            = "#{name}:#{discriminator}"
         count          = cache.count(key, current_period)
+        epoch_time     = cache.last_epoch_time
 
         data = {
           :count => count,
           :period => current_period,
-          :limit => current_limit
+          :limit => current_limit,
+          :epoch_time => epoch_time
         }
-        (req.env['rack.attack.throttle_data'] ||= {})[name] = data
+
+        (request.env['rack.attack.throttle_data'] ||= {})[name] = data
 
         (count > current_limit).tap do |throttled|
           if throttled
-            req.env['rack.attack.matched']             = name
-            req.env['rack.attack.match_discriminator'] = discriminator
-            req.env['rack.attack.match_type']          = type
-            req.env['rack.attack.match_data']          = data
-            Rack::Attack.instrument(req)
+            request.env['rack.attack.matched']             = name
+            request.env['rack.attack.match_discriminator'] = discriminator
+            request.env['rack.attack.match_type']          = type
+            request.env['rack.attack.match_data']          = data
+            Rack::Attack.instrument(request)
           end
         end
       end
diff --git a/lib/rack/attack/track.rb b/lib/rack/attack/track.rb
index e0039e3..dba16ca 100644
--- a/lib/rack/attack/track.rb
+++ b/lib/rack/attack/track.rb
@@ -1,8 +1,8 @@
+# frozen_string_literal: true
+
 module Rack
   class Attack
     class Track
-      extend Forwardable
-
       attr_reader :filter
 
       def initialize(name, options = {}, block)
@@ -15,7 +15,9 @@ module Rack
         end
       end
 
-      def_delegator :@filter, :[]
+      def matched_by?(request)
+        filter.matched_by?(request)
+      end
     end
   end
 end
diff --git a/lib/rack/attack/version.rb b/lib/rack/attack/version.rb
index 06f4df7..07a1d57 100644
--- a/lib/rack/attack/version.rb
+++ b/lib/rack/attack/version.rb
@@ -1,5 +1,7 @@
+# frozen_string_literal: true
+
 module Rack
   class Attack
-    VERSION = '5.0.1'
+    VERSION = '5.3.2'
   end
 end
diff --git a/rack-attack.gemspec b/rack-attack.gemspec
index 1fcdd42..e5828f4 100644
--- a/rack-attack.gemspec
+++ b/rack-attack.gemspec
@@ -1,4 +1,6 @@
 # -*- encoding: utf-8 -*-
+# frozen_string_literal: true
+
 lib = File.expand_path('../lib/', __FILE__)
 $:.unshift lib unless $:.include?(lib)
 
@@ -14,23 +16,38 @@ Gem::Specification.new do |s|
   s.email = "aaron@ktheory.com"
 
   s.files = Dir.glob("{bin,lib}/**/*") + %w(Rakefile README.md)
-  s.homepage = 'http://github.com/kickstarter/rack-attack'
+  s.homepage = 'https://github.com/kickstarter/rack-attack'
   s.rdoc_options = ["--charset=UTF-8"]
   s.require_paths = ["lib"]
   s.summary = %q{Block & throttle abusive requests}
   s.test_files = Dir.glob("spec/**/*")
 
-  s.required_ruby_version = '>= 2.0.0'
+  s.metadata = {
+    "bug_tracker_uri" => "https://github.com/kickstarter/rack-attack/issues",
+    "changelog_uri" => "https://github.com/kickstarter/rack-attack/blob/master/CHANGELOG.md",
+    "source_code_uri" => "https://github.com/kickstarter/rack-attack"
+  }
 
-  s.add_dependency 'rack'
-  s.add_development_dependency 'minitest'
-  s.add_development_dependency 'rack-test'
-  s.add_development_dependency 'rake'
-  s.add_development_dependency 'appraisal'
-  s.add_development_dependency 'activesupport', '>= 3.0.0'
-  s.add_development_dependency 'actionpack', '>= 3.0.0'
-  s.add_development_dependency 'redis-activesupport'
-  s.add_development_dependency 'dalli'
-  s.add_development_dependency 'connection_pool'
-  s.add_development_dependency 'memcache-client'
+  s.required_ruby_version = '>= 2.3'
+
+  s.add_runtime_dependency 'rack', ">= 1.0", "< 3"
+
+  s.add_development_dependency 'appraisal', '~> 2.2'
+  s.add_development_dependency "bundler", "~> 1.16"
+  s.add_development_dependency 'minitest', "~> 5.11"
+  s.add_development_dependency "minitest-stub-const", "~> 0.6"
+  s.add_development_dependency 'rack-test', "~> 1.0"
+  s.add_development_dependency 'rake', "~> 12.3"
+  s.add_development_dependency "rubocop", "0.57.2"
+  s.add_development_dependency "timecop", "~> 0.9.1"
+
+  # byebug only works with MRI
+  if RUBY_ENGINE == "ruby"
+    s.add_development_dependency 'byebug', '~> 10.0'
+  end
+
+  # The following are potential runtime dependencies users may have,
+  # which rack-attack uses only for testing compatibility in test suite.
+  s.add_development_dependency 'actionpack', '~> 5.2'
+  s.add_development_dependency 'activesupport', '~> 5.2'
 end
diff --git a/spec/acceptance/allow2ban_spec.rb b/spec/acceptance/allow2ban_spec.rb
new file mode 100644
index 0000000..6de18d0
--- /dev/null
+++ b/spec/acceptance/allow2ban_spec.rb
@@ -0,0 +1,73 @@
+# frozen_string_literal: true
+
+require_relative "../spec_helper"
+require "timecop"
+
+describe "allow2ban" do
+  before do
+    Rack::Attack.cache.store = ActiveSupport::Cache::MemoryStore.new
+
+    Rack::Attack.blocklist("allow2ban pentesters") do |request|
+      Rack::Attack::Allow2Ban.filter(request.ip, maxretry: 2, findtime: 30, bantime: 60) do
+        request.path.include?("scarce-resource")
+      end
+    end
+  end
+
+  it "returns OK for many requests that doesn't match the filter" do
+    get "/"
+    assert_equal 200, last_response.status
+
+    get "/"
+    assert_equal 200, last_response.status
+  end
+
+  it "returns OK for first request that matches the filter" do
+    get "/scarce-resource"
+    assert_equal 200, last_response.status
+  end
+
+  it "forbids all access after reaching maxretry limit" do
+    get "/scarce-resource"
+    assert_equal 200, last_response.status
+
+    get "/scarce-resource"
+    assert_equal 200, last_response.status
+
+    get "/scarce-resource"
+    assert_equal 403, last_response.status
+
+    get "/"
+    assert_equal 403, last_response.status
+  end
+
+  it "restores access after bantime elapsed" do
+    get "/scarce-resource"
+    assert_equal 200, last_response.status
+
+    get "/scarce-resource"
+    assert_equal 200, last_response.status
+
+    get "/"
+    assert_equal 403, last_response.status
+
+    Timecop.travel(60) do
+      get "/"
+
+      assert_equal 200, last_response.status
+    end
+  end
+
+  it "does not forbid all access if maxrety condition is met but not within the findtime timespan" do
+    get "/scarce-resource"
+    assert_equal 200, last_response.status
+
+    Timecop.travel(31) do
+      get "/scarce-resource"
+      assert_equal 200, last_response.status
+
+      get "/"
+      assert_equal 200, last_response.status
+    end
+  end
+end
diff --git a/spec/acceptance/blocking_ip_spec.rb b/spec/acceptance/blocking_ip_spec.rb
new file mode 100644
index 0000000..cfb2282
--- /dev/null
+++ b/spec/acceptance/blocking_ip_spec.rb
@@ -0,0 +1,40 @@
+# frozen_string_literal: true
+
+require_relative "../spec_helper"
+
+describe "Blocking an IP" do
+  before do
+    Rack::Attack.blocklist_ip("1.2.3.4")
+  end
+
+  it "forbids request if IP matches" do
+    get "/", {}, "REMOTE_ADDR" => "1.2.3.4"
+
+    assert_equal 403, last_response.status
+  end
+
+  it "succeeds if IP doesn't match" do
+    get "/", {}, "REMOTE_ADDR" => "5.6.7.8"
+
+    assert_equal 200, last_response.status
+  end
+
+  it "notifies when the request is blocked" do
+    notified = false
+    notification_type = nil
+
+    ActiveSupport::Notifications.subscribe("rack.attack") do |_name, _start, _finish, _id, payload|
+      notified = true
+      notification_type = payload[:request].env["rack.attack.match_type"]
+    end
+
+    get "/", {}, "REMOTE_ADDR" => "5.6.7.8"
+
+    refute notified
+
+    get "/", {}, "REMOTE_ADDR" => "1.2.3.4"
+
+    assert notified
+    assert_equal :blocklist, notification_type
+  end
+end
diff --git a/spec/acceptance/blocking_spec.rb b/spec/acceptance/blocking_spec.rb
new file mode 100644
index 0000000..db176c8
--- /dev/null
+++ b/spec/acceptance/blocking_spec.rb
@@ -0,0 +1,43 @@
+# frozen_string_literal: true
+
+require_relative "../spec_helper"
+
+describe "#blocklist" do
+  before do
+    Rack::Attack.blocklist("block 1.2.3.4") do |request|
+      request.ip == "1.2.3.4"
+    end
+  end
+
+  it "forbids request if blocklist condition is true" do
+    get "/", {}, "REMOTE_ADDR" => "1.2.3.4"
+
+    assert_equal 403, last_response.status
+  end
+
+  it "succeeds if blocklist condition is false" do
+    get "/", {}, "REMOTE_ADDR" => "5.6.7.8"
+
+    assert_equal 200, last_response.status
+  end
+
+  it "notifies when the request is blocked" do
+    notification_matched = nil
+    notification_type = nil
+
+    ActiveSupport::Notifications.subscribe("rack.attack") do |_name, _start, _finish, _id, payload|
+      notification_matched = payload[:request].env["rack.attack.matched"]
+      notification_type = payload[:request].env["rack.attack.match_type"]
+    end
+
+    get "/", {}, "REMOTE_ADDR" => "5.6.7.8"
+
+    assert_nil notification_matched
+    assert_nil notification_type
+
+    get "/", {}, "REMOTE_ADDR" => "1.2.3.4"
+
+    assert_equal "block 1.2.3.4", notification_matched
+    assert_equal :blocklist, notification_type
+  end
+end
diff --git a/spec/acceptance/blocking_subnet_spec.rb b/spec/acceptance/blocking_subnet_spec.rb
new file mode 100644
index 0000000..1f417d7
--- /dev/null
+++ b/spec/acceptance/blocking_subnet_spec.rb
@@ -0,0 +1,46 @@
+# frozen_string_literal: true
+
+require_relative "../spec_helper"
+
+describe "Blocking an IP subnet" do
+  before do
+    Rack::Attack.blocklist_ip("1.2.3.4/31")
+  end
+
+  it "forbids request if IP is inside the subnet" do
+    get "/", {}, "REMOTE_ADDR" => "1.2.3.4"
+
+    assert_equal 403, last_response.status
+  end
+
+  it "forbids request for another IP in the subnet" do
+    get "/", {}, "REMOTE_ADDR" => "1.2.3.5"
+
+    assert_equal 403, last_response.status
+  end
+
+  it "succeeds if IP is outside the subnet" do
+    get "/", {}, "REMOTE_ADDR" => "1.2.3.6"
+
+    assert_equal 200, last_response.status
+  end
+
+  it "notifies when the request is blocked" do
+    notified = false
+    notification_type = nil
+
+    ActiveSupport::Notifications.subscribe("rack.attack") do |_name, _start, _finish, _id, payload|
+      notified = true
+      notification_type = payload[:request].env["rack.attack.match_type"]
+    end
+
+    get "/", {}, "REMOTE_ADDR" => "5.6.7.8"
+
+    refute notified
+
+    get "/", {}, "REMOTE_ADDR" => "1.2.3.4"
+
+    assert notified
+    assert_equal :blocklist, notification_type
+  end
+end
diff --git a/spec/acceptance/cache_store_config_for_allow2ban_spec.rb b/spec/acceptance/cache_store_config_for_allow2ban_spec.rb
new file mode 100644
index 0000000..09fdab8
--- /dev/null
+++ b/spec/acceptance/cache_store_config_for_allow2ban_spec.rb
@@ -0,0 +1,113 @@
+# frozen_string_literal: true
+
+require_relative "../spec_helper"
+
+describe "Cache store config when using allow2ban" do
+  before do
+    Rack::Attack.blocklist("allow2ban pentesters") do |request|
+      Rack::Attack::Allow2Ban.filter(request.ip, maxretry: 2, findtime: 30, bantime: 60) do
+        request.path.include?("scarce-resource")
+      end
+    end
+  end
+
+  it "gives semantic error if no store was configured" do
+    assert_raises(Rack::Attack::MissingStoreError) do
+      get "/scarce-resource"
+    end
+  end
+
+  it "gives semantic error if store is missing #read method" do
+    basic_store_class = Class.new do
+      def write(key, value)
+      end
+
+      def increment(key, count, options = {})
+      end
+    end
+
+    Rack::Attack.cache.store = basic_store_class.new
+
+    raised_exception = assert_raises(Rack::Attack::MisconfiguredStoreError) do
+      get "/scarce-resource"
+    end
+
+    assert_equal "Store needs to respond to #read", raised_exception.message
+  end
+
+  it "gives semantic error if store is missing #write method" do
+    basic_store_class = Class.new do
+      def read(key)
+      end
+
+      def increment(key, count, options = {})
+      end
+    end
+
+    Rack::Attack.cache.store = basic_store_class.new
+
+    raised_exception = assert_raises(Rack::Attack::MisconfiguredStoreError) do
+      get "/scarce-resource"
+    end
+
+    assert_equal "Store needs to respond to #write", raised_exception.message
+  end
+
+  it "gives semantic error if store is missing #increment method" do
+    basic_store_class = Class.new do
+      def read(key)
+      end
+
+      def write(key, value)
+      end
+    end
+
+    Rack::Attack.cache.store = basic_store_class.new
+
+    raised_exception = assert_raises(Rack::Attack::MisconfiguredStoreError) do
+      get "/scarce-resource"
+    end
+
+    assert_equal "Store needs to respond to #increment", raised_exception.message
+  end
+
+  it "works with any object that responds to #read, #write and #increment" do
+    basic_store_class = Class.new do
+      attr_accessor :backend
+
+      def initialize
+        @backend = {}
+      end
+
+      def read(key)
+        @backend[key]
+      end
+
+      def write(key, value, _options = {})
+        @backend[key] = value
+      end
+
+      def increment(key, _count, _options = {})
+        @backend[key] ||= 0
+        @backend[key] += 1
+      end
+    end
+
+    Rack::Attack.cache.store = basic_store_class.new
+
+    get "/"
+    assert_equal 200, last_response.status
+
+    get "/scarce-resource"
+    assert_equal 200, last_response.status
+
+    get "/scarce-resource"
+    assert_equal 200, last_response.status
+
+    get "/scarce-resource"
+    assert_equal 403, last_response.status
+
+    get "/"
+    assert_equal 403, last_response.status
+  end
+end
diff --git a/spec/acceptance/cache_store_config_for_fail2ban_spec.rb b/spec/acceptance/cache_store_config_for_fail2ban_spec.rb
new file mode 100644
index 0000000..8052fc1
--- /dev/null
+++ b/spec/acceptance/cache_store_config_for_fail2ban_spec.rb
@@ -0,0 +1,110 @@
+# frozen_string_literal: true
+
+require_relative "../spec_helper"
+
+describe "Cache store config when using fail2ban" do
+  before do
+    Rack::Attack.blocklist("fail2ban pentesters") do |request|
+      Rack::Attack::Fail2Ban.filter(request.ip, maxretry: 2, findtime: 30, bantime: 60) do
+        request.path.include?("private-place")
+      end
+    end
+  end
+
+  it "gives semantic error if no store was configured" do
+    assert_raises(Rack::Attack::MissingStoreError) do
+      get "/private-place"
+    end
+  end
+
+  it "gives semantic error if store is missing #read method" do
+    basic_store_class = Class.new do
+      def write(key, value)
+      end
+
+      def increment(key, count, options = {})
+      end
+    end
+
+    Rack::Attack.cache.store = basic_store_class.new
+
+    raised_exception = assert_raises(Rack::Attack::MisconfiguredStoreError) do
+      get "/private-place"
+    end
+
+    assert_equal "Store needs to respond to #read", raised_exception.message
+  end
+
+  it "gives semantic error if store is missing #write method" do
+    basic_store_class = Class.new do
+      def read(key)
+      end
+
+      def increment(key, count, options = {})
+      end
+    end
+
+    Rack::Attack.cache.store = basic_store_class.new
+
+    raised_exception = assert_raises(Rack::Attack::MisconfiguredStoreError) do
+      get "/private-place"
+    end
+
+    assert_equal "Store needs to respond to #write", raised_exception.message
+  end
+
+  it "gives semantic error if store is missing #increment method" do
+    basic_store_class = Class.new do
+      def read(key)
+      end
+
+      def write(key, value)
+      end
+    end
+
+    Rack::Attack.cache.store = basic_store_class.new
+
+    raised_exception = assert_raises(Rack::Attack::MisconfiguredStoreError) do
+      get "/private-place"
+    end
+
+    assert_equal "Store needs to respond to #increment", raised_exception.message
+  end
+
+  it "works with any object that responds to #read, #write and #increment" do
+    basic_store_class = Class.new do
+      attr_accessor :backend
+
+      def initialize
+        @backend = {}
+      end
+
+      def read(key)
+        @backend[key]
+      end
+
+      def write(key, value, _options = {})
+        @backend[key] = value
+      end
+
+      def increment(key, _count, _options = {})
+        @backend[key] ||= 0
+        @backend[key] += 1
+      end
+    end
+
+    Rack::Attack.cache.store = basic_store_class.new
+
+    get "/"
+    assert_equal 200, last_response.status
+
+    get "/private-place"
+    assert_equal 403, last_response.status
+
+    get "/private-place"
+    assert_equal 403, last_response.status
+
+    get "/"
+    assert_equal 403, last_response.status
+  end
+end
diff --git a/spec/acceptance/cache_store_config_for_throttle_spec.rb b/spec/acceptance/cache_store_config_for_throttle_spec.rb
new file mode 100644
index 0000000..9be6e59
--- /dev/null
+++ b/spec/acceptance/cache_store_config_for_throttle_spec.rb
@@ -0,0 +1,50 @@
+# frozen_string_literal: true
+
+require_relative "../spec_helper"
+
+describe "Cache store config when throttling without Rails" do
+  before do
+    Rack::Attack.throttle("by ip", limit: 1, period: 60) do |request|
+      request.ip
+    end
+  end
+
+  it "gives semantic error if no store was configured" do
+    assert_raises(Rack::Attack::MissingStoreError) do
+      get "/", {}, "REMOTE_ADDR" => "1.2.3.4"
+    end
+  end
+
+  it "gives semantic error if incompatible store was configured" do
+    Rack::Attack.cache.store = Object.new
+
+    assert_raises(Rack::Attack::MisconfiguredStoreError) do
+      get "/", {}, "REMOTE_ADDR" => "1.2.3.4"
+    end
+  end
+
+  it "works with any object that responds to #increment" do
+    basic_store_class = Class.new do
+      attr_accessor :counts
+
+      def initialize
+        @counts = {}
+      end
+
+      def increment(key, _count, _options)
+        @counts[key] ||= 0
+        @counts[key] += 1
+      end
+    end
+
+    Rack::Attack.cache.store = basic_store_class.new
+
+    get "/", {}, "REMOTE_ADDR" => "1.2.3.4"
+
+    assert_equal 200, last_response.status
+
+    get "/", {}, "REMOTE_ADDR" => "1.2.3.4"
+
+    assert_equal 429, last_response.status
+  end
+end
diff --git a/spec/acceptance/cache_store_config_with_rails_spec.rb b/spec/acceptance/cache_store_config_with_rails_spec.rb
new file mode 100644
index 0000000..3d9ac22
--- /dev/null
+++ b/spec/acceptance/cache_store_config_with_rails_spec.rb
@@ -0,0 +1,33 @@
+# frozen_string_literal: true
+
+require_relative "../spec_helper"
+require "minitest/stub_const"
+require "ostruct"
+
+describe "Cache store config with Rails" do
+  before do
+    Rack::Attack.throttle("by ip", limit: 1, period: 60) do |request|
+      request.ip
+    end
+  end
+
+  it "fails when Rails.cache is not set" do
+    Object.stub_const(:Rails, OpenStruct.new(cache: nil)) do
+      assert_raises(Rack::Attack::MissingStoreError) do
+        get "/", {}, "REMOTE_ADDR" => "1.2.3.4"
+      end
+    end
+  end
+
+  it "works when Rails.cache is set" do
+    Object.stub_const(:Rails, OpenStruct.new(cache: ActiveSupport::Cache::MemoryStore.new)) do
+      get "/", {}, "REMOTE_ADDR" => "1.2.3.4"
+
+      assert_equal 200, last_response.status
+
+      get "/", {}, "REMOTE_ADDR" => "1.2.3.4"
+
+      assert_equal 429, last_response.status
+    end
+  end
+end
diff --git a/spec/acceptance/customizing_blocked_response_spec.rb b/spec/acceptance/customizing_blocked_response_spec.rb
new file mode 100644
index 0000000..fd830c2
--- /dev/null
+++ b/spec/acceptance/customizing_blocked_response_spec.rb
@@ -0,0 +1,43 @@
+# frozen_string_literal: true
+
+require_relative "../spec_helper"
+
+describe "Customizing block responses" do
+  before do
+    Rack::Attack.blocklist("block 1.2.3.4") do |request|
+      request.ip == "1.2.3.4"
+    end
+  end
+
+  it "can be customized" do
+    get "/", {}, "REMOTE_ADDR" => "1.2.3.4"
+
+    assert_equal 403, last_response.status
+
+    Rack::Attack.blocklisted_response = lambda do |_env|
+      [503, {}, ["Blocked"]]
+    end
+
+    get "/", {}, "REMOTE_ADDR" => "1.2.3.4"
+
+    assert_equal 503, last_response.status
+    assert_equal "Blocked", last_response.body
+  end
+
+  it "exposes match data" do
+    matched = nil
+    match_type = nil
+
+    Rack::Attack.blocklisted_response = lambda do |env|
+      matched = env['rack.attack.matched']
+      match_type = env['rack.attack.match_type']
+
+      [503, {}, ["Blocked"]]
+    end
+
+    get "/", {}, "REMOTE_ADDR" => "1.2.3.4"
+
+    assert_equal "block 1.2.3.4", matched
+    assert_equal :blocklist, match_type
+  end
+end
diff --git a/spec/acceptance/customizing_throttled_response_spec.rb b/spec/acceptance/customizing_throttled_response_spec.rb
new file mode 100644
index 0000000..5c84979
--- /dev/null
+++ b/spec/acceptance/customizing_throttled_response_spec.rb
@@ -0,0 +1,61 @@
+# frozen_string_literal: true
+
+require_relative "../spec_helper"
+
+describe "Customizing throttled response" do
+  before do
+    Rack::Attack.cache.store = ActiveSupport::Cache::MemoryStore.new
+
+    Rack::Attack.throttle("by ip", limit: 1, period: 60) do |request|
+      request.ip
+    end
+  end
+
+  it "can be customized" do
+    get "/", {}, "REMOTE_ADDR" => "1.2.3.4"
+
+    assert_equal 200, last_response.status
+
+    get "/", {}, "REMOTE_ADDR" => "1.2.3.4"
+
+    assert_equal 429, last_response.status
+
+    Rack::Attack.throttled_response = lambda do |_env|
+      [503, {}, ["Throttled"]]
+    end
+
+    get "/", {}, "REMOTE_ADDR" => "1.2.3.4"
+
+    assert_equal 503, last_response.status
+    assert_equal "Throttled", last_response.body
+  end
+
+  it "exposes match data" do
+    matched = nil
+    match_type = nil
+    match_data = nil
+    match_discriminator = nil
+
+    Rack::Attack.throttled_response = lambda do |env|
+      matched = env['rack.attack.matched']
+      match_type = env['rack.attack.match_type']
+      match_data = env['rack.attack.match_data']
+      match_discriminator = env['rack.attack.match_discriminator']
+
+      [429, {}, ["Throttled"]]
+    end
+
+    get "/", {}, "REMOTE_ADDR" => "1.2.3.4"
+    get "/", {}, "REMOTE_ADDR" => "1.2.3.4"
+
+    assert_equal "by ip", matched
+    assert_equal :throttle, match_type
+    assert_equal 60, match_data[:period]
+    assert_equal 1, match_data[:limit]
+    assert_equal 2, match_data[:count]
+    assert_equal "1.2.3.4", match_discriminator
+
+    get "/", {}, "REMOTE_ADDR" => "1.2.3.4"
+    assert_equal 3, match_data[:count]
+  end
+end
diff --git a/spec/acceptance/extending_request_object_spec.rb b/spec/acceptance/extending_request_object_spec.rb
new file mode 100644
index 0000000..a4ea1a6
--- /dev/null
+++ b/spec/acceptance/extending_request_object_spec.rb
@@ -0,0 +1,36 @@
+# frozen_string_literal: true
+
+require_relative "../spec_helper"
+
+describe "Extending the request object" do
+  before do
+    class Rack::Attack::Request
+      def authorized?
+        env["APIKey"] == "private-secret"
+      end
+    end
+
+    Rack::Attack.blocklist("unauthorized requests") do |request|
+      !request.authorized?
+    end
+  end
+
+  # We don't want the extension to leak to other test cases
+  after do
+    class Rack::Attack::Request
+      remove_method :authorized?
+    end
+  end
+
+  it "forbids request if blocklist condition is true" do
+    get "/"
+
+    assert_equal 403, last_response.status
+  end
+
+  it "succeeds if blocklist condition is false" do
+    get "/", {}, "APIKey" => "private-secret"
+
+    assert_equal 200, last_response.status
+  end
+end
diff --git a/spec/acceptance/fail2ban_spec.rb b/spec/acceptance/fail2ban_spec.rb
new file mode 100644
index 0000000..fde67f9
--- /dev/null
+++ b/spec/acceptance/fail2ban_spec.rb
@@ -0,0 +1,78 @@
+# frozen_string_literal: true
+
+require_relative "../spec_helper"
+require "timecop"
+
+describe "fail2ban" do
+  before do
+    Rack::Attack.cache.store = ActiveSupport::Cache::MemoryStore.new
+
+    Rack::Attack.blocklist("fail2ban pentesters") do |request|
+      Rack::Attack::Fail2Ban.filter(request.ip, maxretry: 2, findtime: 30, bantime: 60) do
+        request.path.include?("private-place")
+      end
+    end
+  end
+
+  it "returns OK for many requests to non filtered path" do
+    get "/"
+    assert_equal 200, last_response.status
+
+    get "/"
+    assert_equal 200, last_response.status
+  end
+
+  it "forbids access to private path" do
+    get "/private-place"
+    assert_equal 403, last_response.status
+  end
+
+  it "returns OK for non filtered path if yet not reached maxretry limit" do
+    get "/private-place"
+    assert_equal 403, last_response.status
+
+    get "/"
+    assert_equal 200, last_response.status
+  end
+
+  it "forbids all access after reaching maxretry limit" do
+    get "/private-place"
+    assert_equal 403, last_response.status
+
+    get "/private-place"
+    assert_equal 403, last_response.status
+
+    get "/"
+    assert_equal 403, last_response.status
+  end
+
+  it "restores access after bantime elapsed" do
+    get "/private-place"
+    assert_equal 403, last_response.status
+
+    get "/private-place"
+    assert_equal 403, last_response.status
+
+    get "/"
+    assert_equal 403, last_response.status
+
+    Timecop.travel(60) do
+      get "/"
+
+      assert_equal 200, last_response.status
+    end
+  end
+
+  it "does not forbid all access if maxrety condition is met but not within the findtime timespan" do
+    get "/private-place"
+    assert_equal 403, last_response.status
+
+    Timecop.travel(31) do
+      get "/private-place"
+      assert_equal 403, last_response.status
+
+      get "/"
+      assert_equal 200, last_response.status
+    end
+  end
+end
diff --git a/spec/acceptance/safelisting_ip_spec.rb b/spec/acceptance/safelisting_ip_spec.rb
new file mode 100644
index 0000000..bdf7d67
--- /dev/null
+++ b/spec/acceptance/safelisting_ip_spec.rb
@@ -0,0 +1,50 @@
+# frozen_string_literal: true
+
+require_relative "../spec_helper"
+
+describe "Safelist an IP" do
+  before do
+    Rack::Attack.blocklist("admin") do |request|
+      request.path == "/admin"
+    end
+
+    Rack::Attack.safelist_ip("5.6.7.8")
+  end
+
+  it "forbids request if blocklist condition is true and safelist is false" do
+    get "/admin", {}, "REMOTE_ADDR" => "1.2.3.4"
+
+    assert_equal 403, last_response.status
+  end
+
+  it "succeeds if blocklist condition is false and safelist is false" do
+    get "/", {}, "REMOTE_ADDR" => "1.2.3.4"
+
+    assert_equal 200, last_response.status
+  end
+
+  it "succeeds request if blocklist condition is false and safelist is true" do
+    get "/", {}, "REMOTE_ADDR" => "5.6.7.8"
+
+    assert_equal 200, last_response.status
+  end
+
+  it "succeeds request if both blocklist and safelist conditions are true" do
+    get "/admin", {}, "REMOTE_ADDR" => "5.6.7.8"
+
+    assert_equal 200, last_response.status
+  end
+
+  it "notifies when the request is safe" do
+    notification_type = nil
+
+    ActiveSupport::Notifications.subscribe("rack.attack") do |_name, _start, _finish, _id, payload|
+      notification_type = payload[:request].env["rack.attack.match_type"]
+    end
+
+    get "/admin", {}, "REMOTE_ADDR" => "5.6.7.8"
+
+    assert_equal 200, last_response.status
+    assert_equal :safelist, notification_type
+  end
+end
diff --git a/spec/acceptance/safelisting_spec.rb b/spec/acceptance/safelisting_spec.rb
new file mode 100644
index 0000000..dc4d82d
--- /dev/null
+++ b/spec/acceptance/safelisting_spec.rb
@@ -0,0 +1,55 @@
+# frozen_string_literal: true
+
+require_relative "../spec_helper"
+
+describe "#safelist" do
+  before do
+    Rack::Attack.blocklist("block 1.2.3.4") do |request|
+      request.ip == "1.2.3.4"
+    end
+
+    Rack::Attack.safelist("safe path") do |request|
+      request.path == "/safe_space"
+    end
+  end
+
+  it "forbids request if blocklist condition is true and safelist is false" do
+    get "/", {}, "REMOTE_ADDR" => "1.2.3.4"
+
+    assert_equal 403, last_response.status
+  end
+
+  it "succeeds if blocklist condition is false and safelist is false" do
+    get "/", {}, "REMOTE_ADDR" => "5.6.7.8"
+
+    assert_equal 200, last_response.status
+  end
+
+  it "succeeds request if blocklist condition is false and safelist is true" do
+    get "/safe_space", {}, "REMOTE_ADDR" => "5.6.7.8"
+
+    assert_equal 200, last_response.status
+  end
+
+  it "succeeds request if both blocklist and safelist conditions are true" do
+    get "/safe_space", {}, "REMOTE_ADDR" => "1.2.3.4"
+
+    assert_equal 200, last_response.status
+  end
+
+  it "notifies when the request is safe" do
+    notification_matched = nil
+    notification_type = nil
+
+    ActiveSupport::Notifications.subscribe("rack.attack") do |_name, _start, _finish, _id, payload|
+      notification_matched = payload[:request].env["rack.attack.matched"]
+      notification_type = payload[:request].env["rack.attack.match_type"]
+    end
+
+    get "/safe_space", {}, "REMOTE_ADDR" => "1.2.3.4"
+
+    assert_equal 200, last_response.status
+    assert_equal "safe path", notification_matched
+    assert_equal :safelist, notification_type
+  end
+end
diff --git a/spec/acceptance/safelisting_subnet_spec.rb b/spec/acceptance/safelisting_subnet_spec.rb
new file mode 100644
index 0000000..50d99f6
--- /dev/null
+++ b/spec/acceptance/safelisting_subnet_spec.rb
@@ -0,0 +1,50 @@
+# frozen_string_literal: true
+
+require_relative "../spec_helper"
+
+describe "Safelisting an IP subnet" do
+  before do
+    Rack::Attack.blocklist("admin") do |request|
+      request.path == "/admin"
+    end
+
+    Rack::Attack.safelist_ip("5.6.0.0/16")
+  end
+
+  it "forbids request if blocklist condition is true and safelist is false" do
+    get "/admin", {}, "REMOTE_ADDR" => "5.7.0.0"
+
+    assert_equal 403, last_response.status
+  end
+
+  it "succeeds if blocklist condition is false and safelist is false" do
+    get "/", {}, "REMOTE_ADDR" => "5.7.0.0"
+
+    assert_equal 200, last_response.status
+  end
+
+  it "succeeds request if blocklist condition is false and safelist is true" do
+    get "/", {}, "REMOTE_ADDR" => "5.6.0.0"
+
+    assert_equal 200, last_response.status
+  end
+
+  it "succeeds request if both blocklist and safelist conditions are true" do
+    get "/admin", {}, "REMOTE_ADDR" => "5.6.255.255"
+
+    assert_equal 200, last_response.status
+  end
+
+  it "notifies when the request is safe" do
+    notification_type = nil
+
+    ActiveSupport::Notifications.subscribe("rack.attack") do |_name, _start, _finish, _id, payload|
+      notification_type = payload[:request].env["rack.attack.match_type"]
+    end
+
+    get "/admin", {}, "REMOTE_ADDR" => "5.6.0.0"
+
+    assert_equal 200, last_response.status
+    assert_equal :safelist, notification_type
+  end
+end
diff --git a/spec/acceptance/stores/active_support_dalli_store_spec.rb b/spec/acceptance/stores/active_support_dalli_store_spec.rb
new file mode 100644
index 0000000..45ecf3d
--- /dev/null
+++ b/spec/acceptance/stores/active_support_dalli_store_spec.rb
@@ -0,0 +1,43 @@
+# frozen_string_literal: true
+
+require_relative "../../spec_helper"
+
+if defined?(::Dalli)
+  require_relative "../../support/cache_store_helper"
+  require "active_support/cache/dalli_store"
+  require "timecop"
+
+  describe "ActiveSupport::Cache::DalliStore as a cache backend" do
+    before do
+      Rack::Attack.cache.store = ActiveSupport::Cache::DalliStore.new
+    end
+
+    after do
+      Rack::Attack.cache.store.clear
+    end
+
+    it_works_for_cache_backed_features
+
+    it "doesn't leak keys" do
+      Rack::Attack.throttle("by ip", limit: 1, period: 1) do |request|
+        request.ip
+      end
+
+      key = nil
+
+      # Freeze time during these statement to be sure that the key used by rack attack is the same
+      # we pre-calculate in local variable `key`
+      Timecop.freeze do
+        key = "rack::attack:#{Time.now.to_i}:by ip:1.2.3.4"
+
+        get "/", {}, "REMOTE_ADDR" => "1.2.3.4"
+      end
+
+      assert Rack::Attack.cache.store.fetch(key)
+
+      sleep 2.1
+
+      assert_nil Rack::Attack.cache.store.fetch(key)
+    end
+  end
+end
diff --git a/spec/acceptance/stores/active_support_mem_cache_store_spec.rb b/spec/acceptance/stores/active_support_mem_cache_store_spec.rb
new file mode 100644
index 0000000..86de47c
--- /dev/null
+++ b/spec/acceptance/stores/active_support_mem_cache_store_spec.rb
@@ -0,0 +1,42 @@
+# frozen_string_literal: true
+
+require_relative "../../spec_helper"
+
+if defined?(::Dalli)
+  require_relative "../../support/cache_store_helper"
+  require "timecop"
+
+  describe "ActiveSupport::Cache::MemCacheStore as a cache backend" do
+    before do
+      Rack::Attack.cache.store = ActiveSupport::Cache::MemCacheStore.new
+    end
+
+    after do
+      Rack::Attack.cache.store.flush_all
+    end
+
+    it_works_for_cache_backed_features
+
+    it "doesn't leak keys" do
+      Rack::Attack.throttle("by ip", limit: 1, period: 1) do |request|
+        request.ip
+      end
+
+      key = nil
+
+      # Freeze time during these statement to be sure that the key used by rack attack is the same
+      # we pre-calculate in local variable `key`
+      Timecop.freeze do
+        key = "rack::attack:#{Time.now.to_i}:by ip:1.2.3.4"
+
+        get "/", {}, "REMOTE_ADDR" => "1.2.3.4"
+      end
+
+      assert Rack::Attack.cache.store.get(key)
+
+      sleep 2.1
+
+      assert_nil Rack::Attack.cache.store.get(key)
+    end
+  end
+end
diff --git a/spec/acceptance/stores/active_support_memory_store_spec.rb b/spec/acceptance/stores/active_support_memory_store_spec.rb
new file mode 100644
index 0000000..8657aa2
--- /dev/null
+++ b/spec/acceptance/stores/active_support_memory_store_spec.rb
@@ -0,0 +1,40 @@
+# frozen_string_literal: true
+
+require_relative "../../spec_helper"
+require_relative "../../support/cache_store_helper"
+
+require "timecop"
+
+describe "ActiveSupport::Cache::MemoryStore as a cache backend" do
+  before do
+    Rack::Attack.cache.store = ActiveSupport::Cache::MemoryStore.new
+  end
+
+  after do
+    Rack::Attack.cache.store.clear
+  end
+
+  it_works_for_cache_backed_features
+
+  it "doesn't leak keys" do
+    Rack::Attack.throttle("by ip", limit: 1, period: 1) do |request|
+      request.ip
+    end
+
+    key = nil
+
+    # Freeze time during these statement to be sure that the key used by rack attack is the same
+    # we pre-calculate in local variable `key`
+    Timecop.freeze do
+      key = "rack::attack:#{Time.now.to_i}:by ip:1.2.3.4"
+
+      get "/", {}, "REMOTE_ADDR" => "1.2.3.4"
+    end
+
+    assert Rack::Attack.cache.store.fetch(key)
+
+    sleep 2.1
+
+    assert_nil Rack::Attack.cache.store.fetch(key)
+  end
+end
diff --git a/spec/acceptance/stores/active_support_redis_cache_store_pooled_spec.rb b/spec/acceptance/stores/active_support_redis_cache_store_pooled_spec.rb
new file mode 100644
index 0000000..13da998
--- /dev/null
+++ b/spec/acceptance/stores/active_support_redis_cache_store_pooled_spec.rb
@@ -0,0 +1,42 @@
+# frozen_string_literal: true
+
+require_relative "../../spec_helper"
+
+if defined?(::ConnectionPool) && defined?(::Redis) && defined?(::ActiveSupport::Cache::RedisCacheStore)
+  require_relative "../../support/cache_store_helper"
+  require "timecop"
+
+  describe "ActiveSupport::Cache::RedisCacheStore (pooled) as a cache backend" do
+    before do
+      Rack::Attack.cache.store = ActiveSupport::Cache::RedisCacheStore.new(pool_size: 2)
+    end
+
+    after do
+      Rack::Attack.cache.store.clear
+    end
+
+    it_works_for_cache_backed_features
+
+    it "doesn't leak keys" do
+      Rack::Attack.throttle("by ip", limit: 1, period: 1) do |request|
+        request.ip
+      end
+
+      key = nil
+
+      # Freeze time during these statement to be sure that the key used by rack attack is the same
+      # we pre-calculate in local variable `key`
+      Timecop.freeze do
+        key = "rack::attack:#{Time.now.to_i}:by ip:1.2.3.4"
+
+        get "/", {}, "REMOTE_ADDR" => "1.2.3.4"
+      end
+
+      assert Rack::Attack.cache.store.fetch(key)
+
+      sleep 2.1
+
+      assert_nil Rack::Attack.cache.store.fetch(key)
+    end
+  end
+end
diff --git a/spec/acceptance/stores/active_support_redis_cache_store_spec.rb b/spec/acceptance/stores/active_support_redis_cache_store_spec.rb
new file mode 100644
index 0000000..4303a3f
--- /dev/null
+++ b/spec/acceptance/stores/active_support_redis_cache_store_spec.rb
@@ -0,0 +1,43 @@
+# frozen_string_literal: true
+
+require_relative "../../spec_helper"
+
+if defined?(::Redis) && defined?(::ActiveSupport::Cache::RedisCacheStore)
+  require_relative "../../support/cache_store_helper"
+  require "timecop"
+
+  describe "ActiveSupport::Cache::RedisCacheStore as a cache backend" do
+    before do
+      Rack::Attack.cache.store = ActiveSupport::Cache::RedisCacheStore.new
+    end
+
+    after do
+      Rack::Attack.cache.store.clear
+    end
+
+    it_works_for_cache_backed_features
+
+    it "doesn't leak keys" do
+      Rack::Attack.throttle("by ip", limit: 1, period: 1) do |request|
+        request.ip
+      end
+
+      key = nil
+
+      # Freeze time during these statement to be sure that the key used by rack attack is the same
+      # we pre-calculate in local variable `key`
+      Timecop.freeze do
+        key = "rack::attack:#{Time.now.to_i}:by ip:1.2.3.4"
+
+        # puts key
+        get "/", {}, "REMOTE_ADDR" => "1.2.3.4"
+      end
+
+      assert Rack::Attack.cache.store.fetch(key)
+
+      sleep 2.1
+
+      assert_nil Rack::Attack.cache.store.fetch(key)
+    end
+  end
+end
diff --git a/spec/acceptance/stores/active_support_redis_store_spec.rb b/spec/acceptance/stores/active_support_redis_store_spec.rb
new file mode 100644
index 0000000..9aa7d08
--- /dev/null
+++ b/spec/acceptance/stores/active_support_redis_store_spec.rb
@@ -0,0 +1,42 @@
+# frozen_string_literal: true
+
+require_relative "../../spec_helper"
+
+if defined?(::ActiveSupport::Cache::RedisStore)
+  require_relative "../../support/cache_store_helper"
+  require "timecop"
+
+  describe "ActiveSupport::Cache::RedisStore as a cache backend" do
+    before do
+      Rack::Attack.cache.store = ActiveSupport::Cache::RedisStore.new
+    end
+
+    after do
+      Rack::Attack.cache.store.flushdb
+    end
+
+    it_works_for_cache_backed_features
+
+    it "doesn't leak keys" do
+      Rack::Attack.throttle("by ip", limit: 1, period: 1) do |request|
+        request.ip
+      end
+
+      key = nil
+
+      # Freeze time during these statement to be sure that the key used by rack attack is the same
+      # we pre-calculate in local variable `key`
+      Timecop.freeze do
+        key = "rack::attack:#{Time.now.to_i}:by ip:1.2.3.4"
+
+        get "/", {}, "REMOTE_ADDR" => "1.2.3.4"
+      end
+
+      assert Rack::Attack.cache.store.read(key)
+
+      sleep 2.1
+
+      assert_nil Rack::Attack.cache.store.read(key)
+    end
+  end
+end
diff --git a/spec/acceptance/stores/connection_pool_dalli_client_spec.rb b/spec/acceptance/stores/connection_pool_dalli_client_spec.rb
new file mode 100644
index 0000000..1ccf5d2
--- /dev/null
+++ b/spec/acceptance/stores/connection_pool_dalli_client_spec.rb
@@ -0,0 +1,44 @@
+# frozen_string_literal: true
+
+require_relative "../../spec_helper"
+
+if defined?(::Dalli) && defined?(::ConnectionPool)
+  require_relative "../../support/cache_store_helper"
+  require "connection_pool"
+  require "dalli"
+  require "timecop"
+
+  describe "ConnectionPool with Dalli::Client as a cache backend" do
+    before do
+      Rack::Attack.cache.store = ConnectionPool.new { Dalli::Client.new }
+    end
+
+    after do
+      Rack::Attack.cache.store.with { |client| client.flush_all }
+    end
+
+    it_works_for_cache_backed_features
+
+    it "doesn't leak keys" do
+      Rack::Attack.throttle("by ip", limit: 1, period: 1) do |request|
+        request.ip
+      end
+
+      key = nil
+
+      # Freeze time during these statement to be sure that the key used by rack attack is the same
+      # we pre-calculate in local variable `key`
+      Timecop.freeze do
+        key = "rack::attack:#{Time.now.to_i}:by ip:1.2.3.4"
+
+        get "/", {}, "REMOTE_ADDR" => "1.2.3.4"
+      end
+
+      assert(Rack::Attack.cache.store.with { |client| client.fetch(key) })
+
+      sleep 2.1
+
+      assert_nil(Rack::Attack.cache.store.with { |client| client.fetch(key) })
+    end
+  end
+end
diff --git a/spec/acceptance/stores/dalli_client_spec.rb b/spec/acceptance/stores/dalli_client_spec.rb
new file mode 100644
index 0000000..dedd9ab
--- /dev/null
+++ b/spec/acceptance/stores/dalli_client_spec.rb
@@ -0,0 +1,43 @@
+# frozen_string_literal: true
+
+require_relative "../../spec_helper"
+
+if defined?(::Dalli)
+  require_relative "../../support/cache_store_helper"
+  require "dalli"
+  require "timecop"
+
+  describe "Dalli::Client as a cache backend" do
+    before do
+      Rack::Attack.cache.store = Dalli::Client.new
+    end
+
+    after do
+      Rack::Attack.cache.store.flush_all
+    end
+
+    it_works_for_cache_backed_features
+
+    it "doesn't leak keys" do
+      Rack::Attack.throttle("by ip", limit: 1, period: 1) do |request|
+        request.ip
+      end
+
+      key = nil
+
+      # Freeze time during these statement to be sure that the key used by rack attack is the same
+      # we pre-calculate in local variable `key`
+      Timecop.freeze do
+        key = "rack::attack:#{Time.now.to_i}:by ip:1.2.3.4"
+
+        get "/", {}, "REMOTE_ADDR" => "1.2.3.4"
+      end
+
+      assert Rack::Attack.cache.store.fetch(key)
+
+      sleep 2.1
+
+      assert_nil Rack::Attack.cache.store.fetch(key)
+    end
+  end
+end
diff --git a/spec/acceptance/stores/redis_store_spec.rb b/spec/acceptance/stores/redis_store_spec.rb
new file mode 100644
index 0000000..82898e6
--- /dev/null
+++ b/spec/acceptance/stores/redis_store_spec.rb
@@ -0,0 +1,42 @@
+# frozen_string_literal: true
+
+require_relative "../../spec_helper"
+require_relative "../../support/cache_store_helper"
+
+if defined?(::Redis::Store)
+  require "timecop"
+
+  describe "ActiveSupport::Cache::RedisStore as a cache backend" do
+    before do
+      Rack::Attack.cache.store = ::Redis::Store.new
+    end
+
+    after do
+      Rack::Attack.cache.store.flushdb
+    end
+
+    it_works_for_cache_backed_features
+
+    it "doesn't leak keys" do
+      Rack::Attack.throttle("by ip", limit: 1, period: 1) do |request|
+        request.ip
+      end
+
+      key = nil
+
+      # Freeze time during these statement to be sure that the key used by rack attack is the same
+      # we pre-calculate in local variable `key`
+      Timecop.freeze do
+        key = "rack::attack:#{Time.now.to_i}:by ip:1.2.3.4"
+
+        get "/", {}, "REMOTE_ADDR" => "1.2.3.4"
+      end
+
+      assert Rack::Attack.cache.store.read(key)
+
+      sleep 2.1
+
+      assert_nil Rack::Attack.cache.store.read(key)
+    end
+  end
+end
diff --git a/spec/acceptance/throttling_spec.rb b/spec/acceptance/throttling_spec.rb
new file mode 100644
index 0000000..719def8
--- /dev/null
+++ b/spec/acceptance/throttling_spec.rb
@@ -0,0 +1,161 @@
+# frozen_string_literal: true
+
+require_relative "../spec_helper"
+require "timecop"
+
+describe "#throttle" do
+  before do
+    Rack::Attack.cache.store = ActiveSupport::Cache::MemoryStore.new
+  end
+
+  it "allows one request per minute by IP" do
+    Rack::Attack.throttle("by ip", limit: 1, period: 60) do |request|
+      request.ip
+    end
+
+    get "/", {}, "REMOTE_ADDR" => "1.2.3.4"
+
+    assert_equal 200, last_response.status
+
+    get "/", {}, "REMOTE_ADDR" => "1.2.3.4"
+
+    assert_equal 429, last_response.status
+    assert_equal "60", last_response.headers["Retry-After"]
+    assert_equal "Retry later\n", last_response.body
+
+    get "/", {}, "REMOTE_ADDR" => "5.6.7.8"
+
+    assert_equal 200, last_response.status
+
+    Timecop.travel(60) do
+      get "/", {}, "REMOTE_ADDR" => "1.2.3.4"
+
+      assert_equal 200, last_response.status
+    end
+  end
+
+  it "supports limit to be dynamic" do
+    # Could be used to have different rate limits for authorized
+    # vs general requests
+    limit_proc = lambda do |request|
+      if request.env["X-APIKey"] == "private-secret"
+        2
+      else
+        1
+      end
+    end
+
+    Rack::Attack.throttle("by ip", limit: limit_proc, period: 60) do |request|
+      request.ip
+    end
+
+    get "/", {}, "REMOTE_ADDR" => "1.2.3.4"
+    assert_equal 200, last_response.status
+
+    get "/", {}, "REMOTE_ADDR" => "1.2.3.4"
+    assert_equal 429, last_response.status
+
+    get "/", {}, "REMOTE_ADDR" => "5.6.7.8", "X-APIKey" => "private-secret"
+    assert_equal 200, last_response.status
+
+    get "/", {}, "REMOTE_ADDR" => "5.6.7.8", "X-APIKey" => "private-secret"
+    assert_equal 200, last_response.status
+
+    get "/", {}, "REMOTE_ADDR" => "5.6.7.8", "X-APIKey" => "private-secret"
+    assert_equal 429, last_response.status
+  end
+
+  it "supports period to be dynamic" do
+    # Could be used to have different rate limits for authorized
+    # vs general requests
+    period_proc = lambda do |request|
+      if request.env["X-APIKey"] == "private-secret"
+        10
+      else
+        30
+      end
+    end
+
+    Rack::Attack.throttle("by ip", limit: 1, period: period_proc) do |request|
+      request.ip
+    end
+
+    # Using Time#at to align to start/end of periods exactly
+    # to achieve consistenty in different test runs
+
+    Timecop.travel(Time.at(0)) do
+      get "/", {}, "REMOTE_ADDR" => "1.2.3.4"
+      assert_equal 200, last_response.status
+
+      get "/", {}, "REMOTE_ADDR" => "1.2.3.4"
+      assert_equal 429, last_response.status
+    end
+
+    Timecop.travel(Time.at(10)) do
+      get "/", {}, "REMOTE_ADDR" => "1.2.3.4"
+      assert_equal 429, last_response.status
+    end
+
+    Timecop.travel(Time.at(30)) do
+      get "/", {}, "REMOTE_ADDR" => "1.2.3.4"
+      assert_equal 200, last_response.status
+    end
+
+    Timecop.travel(Time.at(0)) do
+      get "/", {}, "REMOTE_ADDR" => "5.6.7.8", "X-APIKey" => "private-secret"
+      assert_equal 200, last_response.status
+
+      get "/", {}, "REMOTE_ADDR" => "5.6.7.8", "X-APIKey" => "private-secret"
+      assert_equal 429, last_response.status
+    end
+
+    Timecop.travel(Time.at(10)) do
+      get "/", {}, "REMOTE_ADDR" => "5.6.7.8", "X-APIKey" => "private-secret"
+      assert_equal 200, last_response.status
+    end
+  end
+
+  it "notifies when the request is throttled" do
+    Rack::Attack.throttle("by ip", limit: 1, period: 60) do |request|
+      request.ip
+    end
+
+    notification_matched = nil
+    notification_type = nil
+    notification_data = nil
+    notification_discriminator = nil
+
+    ActiveSupport::Notifications.subscribe("rack.attack") do |_name, _start, _finish, _id, payload|
+      notification_matched = payload[:request].env["rack.attack.matched"]
+      notification_type = payload[:request].env["rack.attack.match_type"]
+      notification_data = payload[:request].env['rack.attack.match_data']
+      notification_discriminator = payload[:request].env['rack.attack.match_discriminator']
+    end
+
+    get "/", {}, "REMOTE_ADDR" => "5.6.7.8"
+
+    assert_equal 200, last_response.status
+    assert_nil notification_matched
+    assert_nil notification_type
+    assert_nil notification_data
+    assert_nil notification_discriminator
+
+    get "/", {}, "REMOTE_ADDR" => "1.2.3.4"
+
+    assert_equal 200, last_response.status
+    assert_nil notification_matched
+    assert_nil notification_type
+    assert_nil notification_data
+    assert_nil notification_discriminator
+
+    get "/", {}, "REMOTE_ADDR" => "1.2.3.4"
+
+    assert_equal 429, last_response.status
+    assert_equal "by ip", notification_matched
+    assert_equal :throttle, notification_type
+    assert_equal 60, notification_data[:period]
+    assert_equal 1, notification_data[:limit]
+    assert_equal 2, notification_data[:count]
+    assert_equal "1.2.3.4", notification_discriminator
+  end
+end
diff --git a/spec/acceptance/track_spec.rb b/spec/acceptance/track_spec.rb
new file mode 100644
index 0000000..5f72db8
--- /dev/null
+++ b/spec/acceptance/track_spec.rb
@@ -0,0 +1,29 @@
+# frozen_string_literal: true
+
+require_relative "../spec_helper"
+
+describe "#track" do
+  it "notifies when track block returns true" do
+    Rack::Attack.track("ip 1.2.3.4") do |request|
+      request.ip == "1.2.3.4"
+    end
+
+    notification_matched = nil
+    notification_type = nil
+
+    ActiveSupport::Notifications.subscribe("rack.attack") do |_name, _start, _finish, _id, payload|
+      notification_matched = payload[:request].env["rack.attack.matched"]
+      notification_type = payload[:request].env["rack.attack.match_type"]
+    end
+
+    get "/", {}, "REMOTE_ADDR" => "5.6.7.8"
+
+    assert_nil notification_matched
+    assert_nil notification_type
+
+    get "/", {}, "REMOTE_ADDR" => "1.2.3.4"
+
+    assert_equal "ip 1.2.3.4", notification_matched
+    assert_equal :track, notification_type
+  end
+end
diff --git a/spec/acceptance/track_throttle_spec.rb b/spec/acceptance/track_throttle_spec.rb
new file mode 100644
index 0000000..1d2c5ab
--- /dev/null
+++ b/spec/acceptance/track_throttle_spec.rb
@@ -0,0 +1,55 @@
+# frozen_string_literal: true
+
+require_relative "../spec_helper"
+require "timecop"
+
+describe "#track with throttle-ish options" do
+  it "notifies when throttle goes over the limit without actually throttling requests" do
+    Rack::Attack.cache.store = ActiveSupport::Cache::MemoryStore.new
+
+    Rack::Attack.track("by ip", limit: 1, period: 60) do |request|
+      request.ip
+    end
+
+    notification_matched = nil
+    notification_type = nil
+
+    ActiveSupport::Notifications.subscribe("rack.attack") do |_name, _start, _finish, _id, payload|
+      notification_matched = payload[:request].env["rack.attack.matched"]
+      notification_type = payload[:request].env["rack.attack.match_type"]
+    end
+
+    get "/", {}, "REMOTE_ADDR" => "1.2.3.4"
+
+    assert_nil notification_matched
+    assert_nil notification_type
+
+    assert_equal 200, last_response.status
+
+    get "/", {}, "REMOTE_ADDR" => "5.6.7.8"
+
+    assert_nil notification_matched
+    assert_nil notification_type
+
+    assert_equal 200, last_response.status
+
+    get "/", {}, "REMOTE_ADDR" => "1.2.3.4"
+
+    assert_equal "by ip", notification_matched
+    assert_equal :track, notification_type
+
+    assert_equal 200, last_response.status
+
+    Timecop.travel(60) do
+      notification_matched = nil
+      notification_type = nil
+
+      get "/", {}, "REMOTE_ADDR" => "1.2.3.4"
+
+      assert_nil notification_matched
+      assert_nil notification_type
+
+      assert_equal 200, last_response.status
+    end
+  end
+end
diff --git a/spec/allow2ban_spec.rb b/spec/allow2ban_spec.rb
index 9eeae9c..074a231 100644
--- a/spec/allow2ban_spec.rb
+++ b/spec/allow2ban_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require_relative 'spec_helper'
 
 describe 'Rack::Attack.Allow2Ban' do
@@ -7,10 +9,10 @@ describe 'Rack::Attack.Allow2Ban' do
     @findtime = 60
     @bantime  = 60
     Rack::Attack.cache.store = ActiveSupport::Cache::MemoryStore.new
-    @f2b_options = {:bantime => @bantime, :findtime => @findtime, :maxretry => 2}
+    @f2b_options = { :bantime => @bantime, :findtime => @findtime, :maxretry => 2 }
 
     Rack::Attack.blocklist('pentest') do |req|
-      Rack::Attack::Allow2Ban.filter(req.ip, @f2b_options){req.query_string =~ /OMGHAX/}
+      Rack::Attack::Allow2Ban.filter(req.ip, @f2b_options) { req.query_string =~ /OMGHAX/ }
     end
   end
 
@@ -31,7 +33,7 @@ describe 'Rack::Attack.Allow2Ban' do
         end
 
         it 'increases fail count' do
-          key = "rack::attack:#{Time.now.to_i/@findtime}:allow2ban:count:1.2.3.4"
+          key = "rack::attack:#{Time.now.to_i / @findtime}:allow2ban:count:1.2.3.4"
           @cache.store.read(key).must_equal 1
         end
 
@@ -53,7 +55,7 @@ describe 'Rack::Attack.Allow2Ban' do
         end
 
         it 'increases fail count' do
-          key = "rack::attack:#{Time.now.to_i/@findtime}:allow2ban:count:1.2.3.4"
+          key = "rack::attack:#{Time.now.to_i / @findtime}:allow2ban:count:1.2.3.4"
           @cache.store.read(key).must_equal 2
         end
 
@@ -89,7 +91,7 @@ describe 'Rack::Attack.Allow2Ban' do
       end
 
       it 'does not increase fail count' do
-        key = "rack::attack:#{Time.now.to_i/@findtime}:allow2ban:count:1.2.3.4"
+        key = "rack::attack:#{Time.now.to_i / @findtime}:allow2ban:count:1.2.3.4"
         @cache.store.read(key).must_equal 2
       end
 
@@ -109,7 +111,7 @@ describe 'Rack::Attack.Allow2Ban' do
       end
 
       it 'does not increase fail count' do
-        key = "rack::attack:#{Time.now.to_i/@findtime}:allow2ban:count:1.2.3.4"
+        key = "rack::attack:#{Time.now.to_i / @findtime}:allow2ban:count:1.2.3.4"
         @cache.store.read(key).must_equal 2
       end
 
diff --git a/spec/fail2ban_spec.rb b/spec/fail2ban_spec.rb
index 9d4bcc1..91242f7 100644
--- a/spec/fail2ban_spec.rb
+++ b/spec/fail2ban_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require_relative 'spec_helper'
 
 describe 'Rack::Attack.Fail2Ban' do
@@ -7,10 +9,10 @@ describe 'Rack::Attack.Fail2Ban' do
     @findtime = 60
     @bantime  = 60
     Rack::Attack.cache.store = ActiveSupport::Cache::MemoryStore.new
-    @f2b_options = {:bantime => @bantime, :findtime => @findtime, :maxretry => 2}
+    @f2b_options = { :bantime => @bantime, :findtime => @findtime, :maxretry => 2 }
 
     Rack::Attack.blocklist('pentest') do |req|
-      Rack::Attack::Fail2Ban.filter(req.ip, @f2b_options){req.query_string =~ /OMGHAX/}
+      Rack::Attack::Fail2Ban.filter(req.ip, @f2b_options) { req.query_string =~ /OMGHAX/ }
     end
   end
 
@@ -31,7 +33,7 @@ describe 'Rack::Attack.Fail2Ban' do
         end
 
         it 'increases fail count' do
-          key = "rack::attack:#{Time.now.to_i/@findtime}:fail2ban:count:1.2.3.4"
+          key = "rack::attack:#{Time.now.to_i / @findtime}:fail2ban:count:1.2.3.4"
           @cache.store.read(key).must_equal 1
         end
 
@@ -53,7 +55,7 @@ describe 'Rack::Attack.Fail2Ban' do
         end
 
         it 'increases fail count' do
-          key = "rack::attack:#{Time.now.to_i/@findtime}:fail2ban:count:1.2.3.4"
+          key = "rack::attack:#{Time.now.to_i / @findtime}:fail2ban:count:1.2.3.4"
           @cache.store.read(key).must_equal 2
         end
 
@@ -75,7 +77,7 @@ describe 'Rack::Attack.Fail2Ban' do
         end
 
         it 'resets fail count' do
-          key = "rack::attack:#{Time.now.to_i/@findtime}:fail2ban:count:1.2.3.4"
+          key = "rack::attack:#{Time.now.to_i / @findtime}:fail2ban:count:1.2.3.4"
           assert_nil @cache.store.read(key)
         end
 
@@ -110,7 +112,7 @@ describe 'Rack::Attack.Fail2Ban' do
       end
 
       it 'does not increase fail count' do
-        key = "rack::attack:#{Time.now.to_i/@findtime}:fail2ban:count:1.2.3.4"
+        key = "rack::attack:#{Time.now.to_i / @findtime}:fail2ban:count:1.2.3.4"
         @cache.store.read(key).must_equal 2
       end
 
@@ -130,7 +132,7 @@ describe 'Rack::Attack.Fail2Ban' do
       end
 
       it 'does not increase fail count' do
-        key = "rack::attack:#{Time.now.to_i/@findtime}:fail2ban:count:1.2.3.4"
+        key = "rack::attack:#{Time.now.to_i / @findtime}:fail2ban:count:1.2.3.4"
         @cache.store.read(key).must_equal 2
       end
 
diff --git a/spec/integration/offline_spec.rb b/spec/integration/offline_spec.rb
index f47fb31..1f2cbfa 100644
--- a/spec/integration/offline_spec.rb
+++ b/spec/integration/offline_spec.rb
@@ -1,6 +1,6 @@
+# frozen_string_literal: true
+
 require 'active_support/cache'
-require 'redis-activesupport'
-require 'dalli'
 require_relative '../spec_helper'
 
 OfflineExamples = Minitest::SharedExamples.new do
@@ -17,27 +17,31 @@ OfflineExamples = Minitest::SharedExamples.new do
   end
 end
 
-describe 'when Redis is offline' do
-  include OfflineExamples
+if defined?(::ActiveSupport::Cache::RedisStore)
+  describe 'when Redis is offline' do
+    include OfflineExamples
 
-  before {
-    @cache = Rack::Attack::Cache.new
-    # Use presumably unused port for Redis client
-    @cache.store = ActiveSupport::Cache::RedisStore.new(:host => '127.0.0.1', :port => 3333)
-  }
+    before do
+      @cache = Rack::Attack::Cache.new
+      # Use presumably unused port for Redis client
+      @cache.store = ActiveSupport::Cache::RedisStore.new(:host => '127.0.0.1', :port => 3333)
+    end
+  end
 end
 
-describe 'when Memcached is offline' do
-  include OfflineExamples
+if defined?(::Dalli)
+  describe 'when Memcached is offline' do
+    include OfflineExamples
 
-  before {
-    Dalli.logger.level = Logger::FATAL
+    before do
+      Dalli.logger.level = Logger::FATAL
 
-    @cache = Rack::Attack::Cache.new
-    @cache.store = Dalli::Client.new('127.0.0.1:22122')
-  }
+      @cache = Rack::Attack::Cache.new
+      @cache.store = Dalli::Client.new('127.0.0.1:22122')
+    end
 
-  after {
-    Dalli.logger.level = Logger::INFO
-  }
+    after do
+      Dalli.logger.level = Logger::INFO
+    end
+  end
 end
diff --git a/spec/integration/rack_attack_cache_spec.rb b/spec/integration/rack_attack_cache_spec.rb
deleted file mode 100644
index 354e4ba..0000000
--- a/spec/integration/rack_attack_cache_spec.rb
+++ /dev/null
@@ -1,122 +0,0 @@
-require_relative '../spec_helper'
-
-describe Rack::Attack::Cache do
-  # A convenience method for deleting a key from cache.
-  # Slightly differnet than @cache.delete, which adds a prefix.
-  def delete(key)
-    if @cache.store.respond_to?(:delete)
-      @cache.store.delete(key)
-    else
-      @cache.store.del(key)
-    end
-  end
-
-  def sleep_until_expired
-    sleep(@expires_in * 1.1) # Add 10% to reduce errors
-  end
-
-  require 'active_support/cache/dalli_store'
-  require 'active_support/cache/mem_cache_store'
-  require 'active_support/cache/redis_store'
-  require 'connection_pool'
-
-  cache_stores = [
-    ActiveSupport::Cache::MemoryStore.new,
-    ActiveSupport::Cache::DalliStore.new("127.0.0.1"),
-    ActiveSupport::Cache::RedisStore.new("127.0.0.1"),
-    ActiveSupport::Cache::MemCacheStore.new("127.0.0.1"),
-    Dalli::Client.new,
-    ConnectionPool.new { Dalli::Client.new },
-    Redis::Store.new,
-    Redis.new
-  ]
-
-  cache_stores.each do |store|
-    store = Rack::Attack::StoreProxy.build(store)
-
-    describe "with #{store.class}" do
-      before {
-        @cache = Rack::Attack::Cache.new
-        @key = "rack::attack:cache-test-key"
-        @expires_in = 1
-        @cache.store = store
-        delete(@key)
-      }
-
-      after { delete(@key) }
-
-      describe "do_count once" do
-        it "should be 1" do
-          @cache.send(:do_count, @key, @expires_in).must_equal 1
-        end
-      end
-
-      describe "do_count twice" do
-        it "must be 2" do
-          @cache.send(:do_count, @key, @expires_in)
-          @cache.send(:do_count, @key, @expires_in).must_equal 2
-        end
-      end
-
-      describe "do_count after expires_in" do
-        it "must be 1" do
-          @cache.send(:do_count, @key, @expires_in)
-          sleep_until_expired
-          @cache.send(:do_count, @key, @expires_in).must_equal 1
-        end
-      end
-
-      describe "write" do
-        it "should write a value to the store with prefix" do
-          @cache.write("cache-test-key", "foobar", 1)
-          store.read(@key).must_equal "foobar"
-        end
-      end
-
-      describe "write after expiry" do
-        it "must not have a value" do
-          @cache.write("cache-test-key", "foobar", @expires_in)
-          sleep_until_expired
-          store.read(@key).must_be :nil?
-        end
-      end
-
-      describe "read" do
-        it "must read the value with a prefix" do
-          store.write(@key, "foobar", :expires_in => @expires_in)
-          @cache.read("cache-test-key").must_equal "foobar"
-        end
-      end
-
-      describe "delete" do
-        it "must delete the value" do
-          store.write(@key, "foobar", :expires_in => @expires_in)
-          @cache.read('cache-test-key').must_equal "foobar"
-          store.delete(@key)
-          assert_nil @cache.read('cache-test-key')
-        end
-      end
-
-      describe "cache#delete" do
-        it "must delete the value" do
-          @cache.write("cache-test-key", "foobar", 1)
-          store.read(@key).must_equal "foobar"
-          @cache.delete('cache-test-key')
-          store.read(@key).must_be :nil?
-        end
-      end
-
-      describe "reset_count" do
-        it "must delete the value" do
-          period = 1.minute
-          unprefixed_key = 'cache-test-key'
-          @cache.count(unprefixed_key, period)
-          period_key, _ = @cache.send(:key_and_expiry, 'cache-test-key', period)
-          store.read(period_key).to_i.must_equal 1
-          @cache.reset_count(unprefixed_key, period)
-          assert_nil store.read(period_key)
-        end
-      end
-    end
-  end
-end
diff --git a/spec/rack_attack_dalli_proxy_spec.rb b/spec/rack_attack_dalli_proxy_spec.rb
index 50a2b9c..7eb23f0 100644
--- a/spec/rack_attack_dalli_proxy_spec.rb
+++ b/spec/rack_attack_dalli_proxy_spec.rb
@@ -1,10 +1,10 @@
+# frozen_string_literal: true
+
 require_relative 'spec_helper'
 
 describe Rack::Attack::StoreProxy::DalliProxy do
-
   it 'should stub Dalli::Client#with on older clients' do
     proxy = Rack::Attack::StoreProxy::DalliProxy.new(Class.new)
     proxy.with {} # will not raise an error
   end
-
 end
diff --git a/spec/rack_attack_instrumentation_spec.rb b/spec/rack_attack_instrumentation_spec.rb
new file mode 100644
index 0000000..1bd51a3
--- /dev/null
+++ b/spec/rack_attack_instrumentation_spec.rb
@@ -0,0 +1,33 @@
+# frozen_string_literal: true
+
+# ActiveSupport::Subscribers added in ~> 4.0.2.0
+if ActiveSupport::VERSION::MAJOR > 3
+  require_relative 'spec_helper'
+  require 'active_support/subscriber'
+  class CustomSubscriber < ActiveSupport::Subscriber
+    def rack(event)
+      # Do virtually (but not) nothing.
+      event.inspect
+    end
+  end
+
+  describe 'Rack::Attack.instrument' do
+    before do
+      @period = 60 # Use a long period; failures due to cache key rotation less likely
+      Rack::Attack.cache.store = ActiveSupport::Cache::MemoryStore.new
+      Rack::Attack.throttle('ip/sec', limit: 1, period: @period) { |req| req.ip }
+    end
+
+    describe "with throttling" do
+      before do
+        ActiveSupport::Notifications.stub(:notifier, ActiveSupport::Notifications::Fanout.new) do
+          CustomSubscriber.attach_to("attack")
+          2.times { get '/', {}, 'REMOTE_ADDR' => '1.2.3.4' }
+        end
+      end
+      it 'should instrument without error' do
+        last_response.status.must_equal 429
+      end
+    end
+  end
+end
diff --git a/spec/rack_attack_path_normalizer_spec.rb b/spec/rack_attack_path_normalizer_spec.rb
index 1c5b66e..961491d 100644
--- a/spec/rack_attack_path_normalizer_spec.rb
+++ b/spec/rack_attack_path_normalizer_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require_relative 'spec_helper'
 
 describe Rack::Attack::PathNormalizer do
diff --git a/spec/rack_attack_request_spec.rb b/spec/rack_attack_request_spec.rb
index cc617ae..8d4d27f 100644
--- a/spec/rack_attack_request_spec.rb
+++ b/spec/rack_attack_request_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require_relative 'spec_helper'
 
 describe 'Rack::Attack' do
@@ -14,6 +16,6 @@ describe 'Rack::Attack' do
       end
     end
 
-    allow_ok_requests
+    it_allows_ok_requests
   end
 end
diff --git a/spec/rack_attack_spec.rb b/spec/rack_attack_spec.rb
index 6addd16..d99e89d 100644
--- a/spec/rack_attack_spec.rb
+++ b/spec/rack_attack_spec.rb
@@ -1,11 +1,13 @@
+# frozen_string_literal: true
+
 require_relative 'spec_helper'
 
 describe 'Rack::Attack' do
-  allow_ok_requests
+  it_allows_ok_requests
 
   describe 'normalizing paths' do
     before do
-      Rack::Attack.blocklist("banned_path") {|req| req.path == '/foo' }
+      Rack::Attack.blocklist("banned_path") { |req| req.path == '/foo' }
     end
 
     it 'blocks requests with trailing slash' do
@@ -17,20 +19,13 @@ describe 'Rack::Attack' do
   describe 'blocklist' do
     before do
       @bad_ip = '1.2.3.4'
-      Rack::Attack.blocklist("ip #{@bad_ip}") {|req| req.ip == @bad_ip }
+      Rack::Attack.blocklist("ip #{@bad_ip}") { |req| req.ip == @bad_ip }
     end
 
     it('has a blocklist') {
       Rack::Attack.blocklists.key?("ip #{@bad_ip}").must_equal true
     }
 
-    it('has a blacklist with a deprication warning') {
-      _, stderror  = capture_io do
-        Rack::Attack.blacklists.key?("ip #{@bad_ip}").must_equal true
-      end
-      assert_match "[DEPRECATION] 'Rack::Attack.blacklists' is deprecated.  Please use 'blocklists' instead.", stderror
-    }
-
     describe "a bad request" do
       before { get '/', {}, 'REMOTE_ADDR' => @bad_ip }
 
@@ -44,24 +39,17 @@ describe 'Rack::Attack' do
         last_request.env['rack.attack.match_type'].must_equal :blocklist
       end
 
-      allow_ok_requests
+      it_allows_ok_requests
     end
 
     describe "and safelist" do
       before do
         @good_ua = 'GoodUA'
-        Rack::Attack.safelist("good ua") {|req| req.user_agent == @good_ua }
+        Rack::Attack.safelist("good ua") { |req| req.user_agent == @good_ua }
       end
 
       it('has a safelist') { Rack::Attack.safelists.key?("good ua") }
 
-      it('has a whitelist with a deprication warning') {
-        _, stderror  = capture_io do
-          Rack::Attack.whitelists.key?("good ua")
-        end
-        assert_match "[DEPRECATION] 'Rack::Attack.whitelists' is deprecated.  Please use 'safelists' instead.", stderror
-      }
-
       describe "with a request match both safelist & blocklist" do
         before { get '/', {}, 'REMOTE_ADDR' => @bad_ip, 'HTTP_USER_AGENT' => @good_ua }
 
@@ -80,13 +68,6 @@ describe 'Rack::Attack' do
       it 'should exist' do
         Rack::Attack.blocklisted_response.must_respond_to :call
       end
-
-      it 'should give a deprication warning for blacklisted_response' do
-        _, stderror  = capture_io do
-          Rack::Attack.blacklisted_response
-        end
-        assert_match "[DEPRECATION] 'Rack::Attack.blacklisted_response' is deprecated.  Please use 'blocklisted_response' instead.", stderror
-      end
     end
 
     describe '#throttled_response' do
diff --git a/spec/rack_attack_throttle_spec.rb b/spec/rack_attack_throttle_spec.rb
index 28ab26c..616fea0 100644
--- a/spec/rack_attack_throttle_spec.rb
+++ b/spec/rack_attack_throttle_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require_relative 'spec_helper'
 
 describe 'Rack::Attack.throttle' do
@@ -9,18 +11,18 @@ describe 'Rack::Attack.throttle' do
 
   it('should have a throttle') { Rack::Attack.throttles.key?('ip/sec') }
 
-  allow_ok_requests
+  it_allows_ok_requests
 
   describe 'a single request' do
     before { get '/', {}, 'REMOTE_ADDR' => '1.2.3.4' }
 
     it 'should set the counter for one request' do
-      key = "rack::attack:#{Time.now.to_i/@period}:ip/sec:1.2.3.4"
+      key = "rack::attack:#{Time.now.to_i / @period}:ip/sec:1.2.3.4"
       Rack::Attack.cache.store.read(key).must_equal 1
     end
 
     it 'should populate throttle data' do
-      data = { :count => 1, :limit => 1, :period => @period }
+      data = { :count => 1, :limit => 1, :period => @period, epoch_time: Rack::Attack.cache.last_epoch_time.to_i }
       last_request.env['rack.attack.throttle_data']['ip/sec'].must_equal data
     end
   end
@@ -37,7 +39,7 @@ describe 'Rack::Attack.throttle' do
     it 'should tag the env' do
       last_request.env['rack.attack.matched'].must_equal 'ip/sec'
       last_request.env['rack.attack.match_type'].must_equal :throttle
-      last_request.env['rack.attack.match_data'].must_equal({:count => 2, :limit => 1, :period => @period})
+      last_request.env['rack.attack.match_data'].must_equal(:count => 2, :limit => 1, :period => @period, epoch_time: Rack::Attack.cache.last_epoch_time.to_i)
       last_request.env['rack.attack.match_discriminator'].must_equal('1.2.3.4')
     end
 
@@ -51,21 +53,21 @@ describe 'Rack::Attack.throttle with limit as proc' do
   before do
     @period = 60 # Use a long period; failures due to cache key rotation less likely
     Rack::Attack.cache.store = ActiveSupport::Cache::MemoryStore.new
-    Rack::Attack.throttle('ip/sec', :limit => lambda { |req| 1 }, :period => @period) { |req| req.ip }
+    Rack::Attack.throttle('ip/sec', :limit => lambda { |_req| 1 }, :period => @period) { |req| req.ip }
   end
 
-  allow_ok_requests
+  it_allows_ok_requests
 
   describe 'a single request' do
     before { get '/', {}, 'REMOTE_ADDR' => '1.2.3.4' }
 
     it 'should set the counter for one request' do
-      key = "rack::attack:#{Time.now.to_i/@period}:ip/sec:1.2.3.4"
+      key = "rack::attack:#{Time.now.to_i / @period}:ip/sec:1.2.3.4"
       Rack::Attack.cache.store.read(key).must_equal 1
     end
 
     it 'should populate throttle data' do
-      data = { :count => 1, :limit => 1, :period => @period }
+      data = { :count => 1, :limit => 1, :period => @period, epoch_time: Rack::Attack.cache.last_epoch_time.to_i }
       last_request.env['rack.attack.throttle_data']['ip/sec'].must_equal data
     end
   end
@@ -75,21 +77,21 @@ describe 'Rack::Attack.throttle with period as proc' do
   before do
     @period = 60 # Use a long period; failures due to cache key rotation less likely
     Rack::Attack.cache.store = ActiveSupport::Cache::MemoryStore.new
-    Rack::Attack.throttle('ip/sec', :limit => lambda { |req| 1 }, :period => lambda { |req| @period }) { |req| req.ip }
+    Rack::Attack.throttle('ip/sec', :limit => lambda { |_req| 1 }, :period => lambda { |_req| @period }) { |req| req.ip }
   end
 
-  allow_ok_requests
+  it_allows_ok_requests
 
   describe 'a single request' do
     before { get '/', {}, 'REMOTE_ADDR' => '1.2.3.4' }
 
     it 'should set the counter for one request' do
-      key = "rack::attack:#{Time.now.to_i/@period}:ip/sec:1.2.3.4"
+      key = "rack::attack:#{Time.now.to_i / @period}:ip/sec:1.2.3.4"
       Rack::Attack.cache.store.read(key).must_equal 1
     end
 
     it 'should populate throttle data' do
-      data = { :count => 1, :limit => 1, :period => @period }
+      data = { :count => 1, :limit => 1, :period => @period, epoch_time: Rack::Attack.cache.last_epoch_time.to_i }
       last_request.env['rack.attack.throttle_data']['ip/sec'].must_equal data
     end
   end
@@ -102,13 +104,13 @@ describe 'Rack::Attack.throttle with block retuning nil' do
     Rack::Attack.throttle('ip/sec', :limit => 1, :period => @period) { |_| nil }
   end
 
-  allow_ok_requests
+  it_allows_ok_requests
 
   describe 'a single request' do
     before { get '/', {}, 'REMOTE_ADDR' => '1.2.3.4' }
 
     it 'should not set the counter' do
-      key = "rack::attack:#{Time.now.to_i/@period}:ip/sec:1.2.3.4"
+      key = "rack::attack:#{Time.now.to_i / @period}:ip/sec:1.2.3.4"
       assert_nil Rack::Attack.cache.store.read(key)
     end
 
diff --git a/spec/rack_attack_track_spec.rb b/spec/rack_attack_track_spec.rb
index 6bd38f3..39c6ab9 100644
--- a/spec/rack_attack_track_spec.rb
+++ b/spec/rack_attack_track_spec.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require_relative 'spec_helper'
 
 describe 'Rack::Attack.track' do
@@ -16,10 +18,10 @@ describe 'Rack::Attack.track' do
   end
 
   before do
-    Rack::Attack.track("everything"){ |req| true }
+    Rack::Attack.track("everything") { |_req| true }
   end
 
-  allow_ok_requests
+  it_allows_ok_requests
 
   it "should tag the env" do
     get '/'
@@ -31,9 +33,9 @@ describe 'Rack::Attack.track' do
     before do
       Counter.reset
       # A second track
-      Rack::Attack.track("homepage"){ |req| req.path == "/"}
+      Rack::Attack.track("homepage") { |req| req.path == "/" }
 
-      ActiveSupport::Notifications.subscribe("rack.attack") do |*args|
+      ActiveSupport::Notifications.subscribe("rack.attack") do |*_args|
         Counter.incr
       end
 
@@ -47,15 +49,15 @@ describe 'Rack::Attack.track' do
 
   describe "without limit and period options" do
     it "should assign the track filter to a Check instance" do
-      tracker = Rack::Attack.track("homepage") { |req| req.path == "/"}
-      tracker.filter.class.must_equal Rack::Attack::Check
+      track = Rack::Attack.track("homepage") { |req| req.path == "/" }
+      track.filter.class.must_equal Rack::Attack::Check
     end
   end
 
   describe "with limit and period options" do
     it "should assign the track filter to a Throttle instance" do
-      tracker = Rack::Attack.track("homepage", :limit => 10, :period => 10) { |req| req.path == "/"}
-      tracker.filter.class.must_equal Rack::Attack::Throttle
+      track = Rack::Attack.track("homepage", :limit => 10, :period => 10) { |req| req.path == "/" }
+      track.filter.class.must_equal Rack::Attack::Throttle
     end
   end
 end
diff --git a/spec/spec_helper.rb b/spec/spec_helper.rb
index b7d535f..b46161e 100644
--- a/spec/spec_helper.rb
+++ b/spec/spec_helper.rb
@@ -1,4 +1,5 @@
-require "rubygems"
+# frozen_string_literal: true
+
 require "bundler/setup"
 
 require "minitest/autorun"
@@ -9,26 +10,51 @@ require 'action_dispatch'
 
 require "rack/attack"
 
-begin
-  require 'pry'
-rescue LoadError
-  #nothing to do here
+if RUBY_ENGINE == "ruby"
+  require "byebug"
 end
 
-class MiniTest::Spec
+def safe_require(name)
+  begin
+    require name
+  rescue LoadError
+  end
+end
 
+safe_require "connection_pool"
+safe_require "dalli"
+safe_require "redis"
+safe_require "redis-activesupport"
+safe_require "redis-store"
+
+class MiniTest::Spec
   include Rack::Test::Methods
 
-  after { Rack::Attack.clear! }
-
-  def app
-    Rack::Builder.new {
-      use Rack::Attack
-      run lambda {|env| [200, {}, ['Hello World']]}
-    }.to_app
+  before do
+    @_original_throttled_response = Rack::Attack.throttled_response
+    @_original_blocklisted_response = Rack::Attack.blocklisted_response
   end
 
-  def self.allow_ok_requests
+  after do
+    Rack::Attack.clear_configuration
+    Rack::Attack.instance_variable_set(:@cache, nil)
+
+    Rack::Attack.throttled_response = @_original_throttled_response
+    Rack::Attack.blocklisted_response = @_original_blocklisted_response
+  end
+
+  def app
+    Rack::Builder.new do
+      # Use Rack::Lint to test that rack-attack is complying with the rack spec
+      use Rack::Lint
+      use Rack::Attack
+      use Rack::Lint
+
+      run lambda { |_env| [200, {}, ['Hello World']] }
+    end.to_app
+  end
+
+  def self.it_allows_ok_requests
     it "must allow ok requests" do
       get '/', {}, 'REMOTE_ADDR' => '127.0.0.1'
       last_response.status.must_equal 200
diff --git a/spec/support/cache_store_helper.rb b/spec/support/cache_store_helper.rb
new file mode 100644
index 0000000..7655949
--- /dev/null
+++ b/spec/support/cache_store_helper.rb
@@ -0,0 +1,60 @@
+# frozen_string_literal: true
+
+class Minitest::Spec
+  def self.it_works_for_cache_backed_features
+    it "works for throttle" do
+      Rack::Attack.throttle("by ip", limit: 1, period: 60) do |request|
+        request.ip
+      end
+
+      get "/", {}, "REMOTE_ADDR" => "1.2.3.4"
+      assert_equal 200, last_response.status
+
+      get "/", {}, "REMOTE_ADDR" => "1.2.3.4"
+      assert_equal 429, last_response.status
+    end
+
+    it "works for fail2ban" do
+      Rack::Attack.blocklist("fail2ban pentesters") do |request|
+        Rack::Attack::Fail2Ban.filter(request.ip, maxretry: 2, findtime: 30, bantime: 60) do
+          request.path.include?("private-place")
+        end
+      end
+
+      get "/"
+      assert_equal 200, last_response.status
+
+      get "/private-place"
+      assert_equal 403, last_response.status
+
+      get "/private-place"
+      assert_equal 403, last_response.status
+
+      get "/"
+      assert_equal 403, last_response.status
+    end
+
+    it "works for allow2ban" do
+      Rack::Attack.blocklist("allow2ban pentesters") do |request|
+        Rack::Attack::Allow2Ban.filter(request.ip, maxretry: 2, findtime: 30, bantime: 60) do
+          request.path.include?("scarce-resource")
+        end
+      end
+
+      get "/"
+      assert_equal 200, last_response.status
+
+      get "/scarce-resource"
+      assert_equal 200, last_response.status
+
+      get "/scarce-resource"
+      assert_equal 200, last_response.status
+
+      get "/scarce-resource"
+      assert_equal 403, last_response.status
+
+      get "/"
+      assert_equal 403, last_response.status
+    end
+  end
+end