diff --git a/.github/workflows/check_changelog.yml b/.github/workflows/check_changelog.yml
index 1e9febe..2c9b08f 100644
--- a/.github/workflows/check_changelog.yml
+++ b/.github/workflows/check_changelog.yml
@@ -1,13 +1,22 @@
 name: Check Changelog
 
 on:
- pull_request:
-  types: [opened, reopened, edited, synchronize]
+  pull_request:
+    types: [opened, reopened, edited, labeled, unlabeled, synchronize]
+
 jobs:
-  build:
+  check-changelog:
     runs-on: ubuntu-latest
+    if: |
+      !contains(github.event.pull_request.body, '[skip changelog]') &&
+      !contains(github.event.pull_request.body, '[changelog skip]') &&
+      !contains(github.event.pull_request.body, '[skip ci]') &&
+      !contains(github.event.pull_request.labels.*.name, 'skip changelog') &&
+      !contains(github.event.pull_request.labels.*.name, 'dependencies') &&
+      !contains(github.event.pull_request.labels.*.name, 'automation')
     steps:
-    - uses: actions/checkout@v1
-    - name: Check that CHANGELOG is touched
-      run: |
-        cat $GITHUB_EVENT_PATH | jq .pull_request.title |  grep -i '\[\(\(changelog skip\)\|\(ci skip\)\)\]' ||  git diff remotes/origin/${{ github.base_ref }} --name-only | grep CHANGELOG.md
+      - uses: actions/checkout@v3
+      - name: Check that CHANGELOG is touched
+        run: |
+          git fetch origin ${{ github.base_ref }} --depth 1 && \
+          git diff remotes/origin/${{ github.base_ref }} --name-only | grep CHANGELOG.md
diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
new file mode 100644
index 0000000..aac9993
--- /dev/null
+++ b/.github/workflows/ci.yml
@@ -0,0 +1,36 @@
+name: CI
+
+on:
+  - push
+  - pull_request
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        ruby:
+          - '2.7'
+          - '3.0'
+          - '3.1'
+          # - 'head'
+        gemfile:
+          - gemfiles/rails_6_0.gemfile
+          - gemfiles/rails_6_1.gemfile
+          - gemfiles/rails_7_0.gemfile
+          # - gemfile: gemfiles/rails_head.gemfile
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v3
+      - name: Set up Ruby
+        env:
+          BUNDLE_GEMFILE: ${{ matrix.gemfile }}
+        uses: ruby/setup-ruby@v1
+        with:
+          ruby-version: ${{ matrix.ruby }}
+          bundler-cache: true
+      - name: Run test
+        env:
+          BUNDLE_GEMFILE: ${{ matrix.gemfile }}
+        run: bundle exec rake test
diff --git a/Appraisals b/Appraisals
index 76a289a..c32c53f 100644
--- a/Appraisals
+++ b/Appraisals
@@ -1,24 +1,28 @@
-appraise "rails-5" do
-  gem "rails", "5.0.7.2"
-  gem "sqlite3", "~> 1.3.6"
+appraise "rails_5_2" do
+  gem "rails", "5.2.3"
+  gem "sqlite3", "~> 1.4"
+  gem 'net-smtp', require: false
 end
 
-appraise "rails-51" do
-  gem "rails", "5.1.7"
-  gem "sqlite3", "~> 1.3.6"
+appraise "rails_6_0" do
+  gem "rails", "6.0.5"
+  gem "sqlite3", "~> 1.4"
+  gem 'net-smtp', require: false
 end
 
-appraise "rails-52" do
-  gem "rails", "5.2.3"
-  gem "sqlite3", "~> 1.3.6"
+appraise "rails_6_1" do
+  gem "rails", "6.1.6"
+  gem "sqlite3", "~> 1.4"
+  gem 'net-smtp', require: false
 end
 
-appraise "rails-6" do
-  gem "rails", "6.0.0"
+appraise "rails_7_0" do
+  gem "rails", "7.0.3"
   gem "sqlite3", "~> 1.4"
 end
 
-appraise "rails-head" do
+appraise "rails_head" do
   gem "rails", git: "https://github.com/rails/rails.git"
+  gem "railties", git: "https://github.com/rails/rails.git"
   gem "sqlite3", "~> 1.4"
 end
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 86144e2..178e78a 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,7 @@
 ## HEAD (Unreleased)
 
+- Add support for Rails 7 (https://github.com/zombocom/maildown/pull/61)
+
 ## 3.3.0
 
 - Delay loading of ActionMailer to fix support for `delivery_job` config (https://github.com/codetriage/maildown/pull/56)
diff --git a/README.md b/README.md
index ca8f7b0..07b7320 100644
--- a/README.md
+++ b/README.md
@@ -1,12 +1,16 @@
 # Maildown
 
-[Markdown](http://daringfireball.net/projects/markdown/syntax) for your ActionMailer-generated emails. Supports Rails 5.0+
+[Markdown](http://daringfireball.net/projects/markdown/syntax) for your ActionMailer-generated emails.
 
 Also due to the way it's implemented it extends markdown support for any other view you want to look for. It could be called `markdown-rails` or something, but this is what I named the gem and I'm sticking with it.
 
 [![Build Status](https://travis-ci.org/codetriage/maildown.svg?branch=schneems%2F2.0.0)](https://travis-ci.org/schneems/maildown)
 [![Help Contribute to Open Source](https://www.codetriage.com/schneems/maildown/badges/users.svg)](https://www.codetriage.com/schneems/maildown)
 
+## Maintenance policy
+
+Follows the Rails maintenance policy https://guides.rubyonrails.org/maintenance_policy.html under "Severe Security Issues". Versions of Rails still under maintenance for Severe Security Issues should be expected to work with Maildown.
+
 ## What?
 
 - Fact: You should always send emails in `text/html` and `text/plain` at the same time
@@ -203,21 +207,22 @@ Features we have that they don't:
 - Their gem is unmaintained, but honestly it's pretty simple and will keep working for some time.
 - We have way more monkeypatches than they do 🙀.
 
-
 ## Test
 
-We use the appraisal gem to generate Gemfiles. Install all dependencies with this:
+We use the [appraisal gem](https://github.com/thoughtbot/appraisal) to generate Gemfiles. Install all dependencies with this:
 
 ```
-$ appraisal install
+$ bundle exec appraisal install
 ```
 
 Run a specific suite like this:
 
 ```
-$ BUNDLE_GEMFILE=gemfiles/rails_6.gemfile bundle exec rake test
+$ BUNDLE_GEMFILE=gemfiles/rails_7_0.gemfile bundle exec rake test
 ```
 
+To add a new test case modify the `Appraisals` file in root and then re-run `bundle exec appraisal install`.
+
 ## License
 
 MIT
diff --git a/gemfiles/rails_5.gemfile.lock b/gemfiles/rails_5.gemfile.lock
deleted file mode 100644
index 1c1d932..0000000
--- a/gemfiles/rails_5.gemfile.lock
+++ /dev/null
@@ -1,137 +0,0 @@
-PATH
-  remote: ..
-  specs:
-    maildown (3.2.0)
-      actionmailer (>= 4.0.0)
-      kramdown-parser-gfm
-
-GEM
-  remote: https://rubygems.org/
-  specs:
-    actioncable (5.0.7.2)
-      actionpack (= 5.0.7.2)
-      nio4r (>= 1.2, < 3.0)
-      websocket-driver (~> 0.6.1)
-    actionmailer (5.0.7.2)
-      actionpack (= 5.0.7.2)
-      actionview (= 5.0.7.2)
-      activejob (= 5.0.7.2)
-      mail (~> 2.5, >= 2.5.4)
-      rails-dom-testing (~> 2.0)
-    actionpack (5.0.7.2)
-      actionview (= 5.0.7.2)
-      activesupport (= 5.0.7.2)
-      rack (~> 2.0)
-      rack-test (~> 0.6.3)
-      rails-dom-testing (~> 2.0)
-      rails-html-sanitizer (~> 1.0, >= 1.0.2)
-    actionview (5.0.7.2)
-      activesupport (= 5.0.7.2)
-      builder (~> 3.1)
-      erubis (~> 2.7.0)
-      rails-dom-testing (~> 2.0)
-      rails-html-sanitizer (~> 1.0, >= 1.0.3)
-    activejob (5.0.7.2)
-      activesupport (= 5.0.7.2)
-      globalid (>= 0.3.6)
-    activemodel (5.0.7.2)
-      activesupport (= 5.0.7.2)
-    activerecord (5.0.7.2)
-      activemodel (= 5.0.7.2)
-      activesupport (= 5.0.7.2)
-      arel (~> 7.0)
-    activesupport (5.0.7.2)
-      concurrent-ruby (~> 1.0, >= 1.0.2)
-      i18n (>= 0.7, < 2)
-      minitest (~> 5.1)
-      tzinfo (~> 1.1)
-    appraisal (2.2.0)
-      bundler
-      rake
-      thor (>= 0.14.0)
-    arel (7.1.4)
-    builder (3.2.3)
-    concurrent-ruby (1.1.5)
-    crass (1.0.4)
-    erubis (2.7.0)
-    globalid (0.4.2)
-      activesupport (>= 4.2.0)
-    i18n (1.6.0)
-      concurrent-ruby (~> 1.0)
-    kramdown (2.3.0)
-      rexml
-    kramdown-parser-gfm (1.1.0)
-      kramdown (~> 2.0)
-    loofah (2.2.3)
-      crass (~> 1.0.2)
-      nokogiri (>= 1.5.9)
-    m (1.5.1)
-      method_source (>= 0.6.7)
-      rake (>= 0.9.2.2)
-    mail (2.7.1)
-      mini_mime (>= 0.1.1)
-    method_source (0.9.2)
-    mini_mime (1.0.1)
-    mini_portile2 (2.4.0)
-    minitest (5.11.3)
-    nio4r (2.3.1)
-    nokogiri (1.10.3)
-      mini_portile2 (~> 2.4.0)
-    rack (2.0.7)
-    rack-test (0.6.3)
-      rack (>= 1.0)
-    rails (5.0.7.2)
-      actioncable (= 5.0.7.2)
-      actionmailer (= 5.0.7.2)
-      actionpack (= 5.0.7.2)
-      actionview (= 5.0.7.2)
-      activejob (= 5.0.7.2)
-      activemodel (= 5.0.7.2)
-      activerecord (= 5.0.7.2)
-      activesupport (= 5.0.7.2)
-      bundler (>= 1.3.0)
-      railties (= 5.0.7.2)
-      sprockets-rails (>= 2.0.0)
-    rails-dom-testing (2.0.3)
-      activesupport (>= 4.2.0)
-      nokogiri (>= 1.6)
-    rails-html-sanitizer (1.0.4)
-      loofah (~> 2.2, >= 2.2.2)
-    railties (5.0.7.2)
-      actionpack (= 5.0.7.2)
-      activesupport (= 5.0.7.2)
-      method_source
-      rake (>= 0.8.7)
-      thor (>= 0.18.1, < 2.0)
-    rake (12.3.2)
-    rexml (3.2.4)
-    sprockets (3.7.2)
-      concurrent-ruby (~> 1.0)
-      rack (> 1, < 3)
-    sprockets-rails (3.2.1)
-      actionpack (>= 4.0)
-      activesupport (>= 4.0)
-      sprockets (>= 3.0.0)
-    sqlite3 (1.3.13)
-    thor (0.20.3)
-    thread_safe (0.3.6)
-    tzinfo (1.2.5)
-      thread_safe (~> 0.1)
-    websocket-driver (0.6.5)
-      websocket-extensions (>= 0.1.0)
-    websocket-extensions (0.1.3)
-
-PLATFORMS
-  ruby
-
-DEPENDENCIES
-  appraisal
-  m
-  maildown!
-  rails (= 5.0.7.2)
-  railties
-  rake
-  sqlite3 (~> 1.3.6)
-
-BUNDLED WITH
-   2.1.4
diff --git a/gemfiles/rails_51.gemfile.lock b/gemfiles/rails_51.gemfile.lock
deleted file mode 100644
index 068b86b..0000000
--- a/gemfiles/rails_51.gemfile.lock
+++ /dev/null
@@ -1,137 +0,0 @@
-PATH
-  remote: ..
-  specs:
-    maildown (3.2.0)
-      actionmailer (>= 4.0.0)
-      kramdown-parser-gfm
-
-GEM
-  remote: https://rubygems.org/
-  specs:
-    actioncable (5.1.7)
-      actionpack (= 5.1.7)
-      nio4r (~> 2.0)
-      websocket-driver (~> 0.6.1)
-    actionmailer (5.1.7)
-      actionpack (= 5.1.7)
-      actionview (= 5.1.7)
-      activejob (= 5.1.7)
-      mail (~> 2.5, >= 2.5.4)
-      rails-dom-testing (~> 2.0)
-    actionpack (5.1.7)
-      actionview (= 5.1.7)
-      activesupport (= 5.1.7)
-      rack (~> 2.0)
-      rack-test (>= 0.6.3)
-      rails-dom-testing (~> 2.0)
-      rails-html-sanitizer (~> 1.0, >= 1.0.2)
-    actionview (5.1.7)
-      activesupport (= 5.1.7)
-      builder (~> 3.1)
-      erubi (~> 1.4)
-      rails-dom-testing (~> 2.0)
-      rails-html-sanitizer (~> 1.0, >= 1.0.3)
-    activejob (5.1.7)
-      activesupport (= 5.1.7)
-      globalid (>= 0.3.6)
-    activemodel (5.1.7)
-      activesupport (= 5.1.7)
-    activerecord (5.1.7)
-      activemodel (= 5.1.7)
-      activesupport (= 5.1.7)
-      arel (~> 8.0)
-    activesupport (5.1.7)
-      concurrent-ruby (~> 1.0, >= 1.0.2)
-      i18n (>= 0.7, < 2)
-      minitest (~> 5.1)
-      tzinfo (~> 1.1)
-    appraisal (2.2.0)
-      bundler
-      rake
-      thor (>= 0.14.0)
-    arel (8.0.0)
-    builder (3.2.3)
-    concurrent-ruby (1.1.5)
-    crass (1.0.4)
-    erubi (1.8.0)
-    globalid (0.4.2)
-      activesupport (>= 4.2.0)
-    i18n (1.6.0)
-      concurrent-ruby (~> 1.0)
-    kramdown (2.3.0)
-      rexml
-    kramdown-parser-gfm (1.1.0)
-      kramdown (~> 2.0)
-    loofah (2.2.3)
-      crass (~> 1.0.2)
-      nokogiri (>= 1.5.9)
-    m (1.5.1)
-      method_source (>= 0.6.7)
-      rake (>= 0.9.2.2)
-    mail (2.7.1)
-      mini_mime (>= 0.1.1)
-    method_source (0.9.2)
-    mini_mime (1.0.1)
-    mini_portile2 (2.4.0)
-    minitest (5.11.3)
-    nio4r (2.3.1)
-    nokogiri (1.10.3)
-      mini_portile2 (~> 2.4.0)
-    rack (2.0.7)
-    rack-test (1.1.0)
-      rack (>= 1.0, < 3)
-    rails (5.1.7)
-      actioncable (= 5.1.7)
-      actionmailer (= 5.1.7)
-      actionpack (= 5.1.7)
-      actionview (= 5.1.7)
-      activejob (= 5.1.7)
-      activemodel (= 5.1.7)
-      activerecord (= 5.1.7)
-      activesupport (= 5.1.7)
-      bundler (>= 1.3.0)
-      railties (= 5.1.7)
-      sprockets-rails (>= 2.0.0)
-    rails-dom-testing (2.0.3)
-      activesupport (>= 4.2.0)
-      nokogiri (>= 1.6)
-    rails-html-sanitizer (1.0.4)
-      loofah (~> 2.2, >= 2.2.2)
-    railties (5.1.7)
-      actionpack (= 5.1.7)
-      activesupport (= 5.1.7)
-      method_source
-      rake (>= 0.8.7)
-      thor (>= 0.18.1, < 2.0)
-    rake (12.3.2)
-    rexml (3.2.4)
-    sprockets (3.7.2)
-      concurrent-ruby (~> 1.0)
-      rack (> 1, < 3)
-    sprockets-rails (3.2.1)
-      actionpack (>= 4.0)
-      activesupport (>= 4.0)
-      sprockets (>= 3.0.0)
-    sqlite3 (1.3.13)
-    thor (0.20.3)
-    thread_safe (0.3.6)
-    tzinfo (1.2.5)
-      thread_safe (~> 0.1)
-    websocket-driver (0.6.5)
-      websocket-extensions (>= 0.1.0)
-    websocket-extensions (0.1.3)
-
-PLATFORMS
-  ruby
-
-DEPENDENCIES
-  appraisal
-  m
-  maildown!
-  rails (= 5.1.7)
-  railties
-  rake
-  sqlite3 (~> 1.3.6)
-
-BUNDLED WITH
-   2.1.4
diff --git a/gemfiles/rails_52.gemfile b/gemfiles/rails_5_2.gemfile
similarity index 70%
rename from gemfiles/rails_52.gemfile
rename to gemfiles/rails_5_2.gemfile
index 10793d5..abfcf2e 100644
--- a/gemfiles/rails_52.gemfile
+++ b/gemfiles/rails_5_2.gemfile
@@ -4,6 +4,7 @@ source "https://rubygems.org"
 
 gem "appraisal"
 gem "rails", "5.2.3"
-gem "sqlite3", "~> 1.3.6"
+gem "sqlite3", "~> 1.4"
+gem "net-smtp", require: false
 
 gemspec path: "../"
diff --git a/gemfiles/rails_52.gemfile.lock b/gemfiles/rails_5_2.gemfile.lock
similarity index 70%
rename from gemfiles/rails_52.gemfile.lock
rename to gemfiles/rails_5_2.gemfile.lock
index c3f51a7..65e153a 100644
--- a/gemfiles/rails_52.gemfile.lock
+++ b/gemfiles/rails_5_2.gemfile.lock
@@ -1,7 +1,7 @@
 PATH
   remote: ..
   specs:
-    maildown (3.2.0)
+    maildown (3.3.0)
       actionmailer (>= 4.0.0)
       kramdown-parser-gfm
 
@@ -49,42 +49,53 @@ GEM
       i18n (>= 0.7, < 2)
       minitest (~> 5.1)
       tzinfo (~> 1.1)
-    appraisal (2.2.0)
+    appraisal (2.4.1)
       bundler
       rake
       thor (>= 0.14.0)
     arel (9.0.0)
-    builder (3.2.3)
-    concurrent-ruby (1.1.5)
-    crass (1.0.4)
-    erubi (1.8.0)
-    globalid (0.4.2)
-      activesupport (>= 4.2.0)
-    i18n (1.6.0)
+    builder (3.2.4)
+    concurrent-ruby (1.1.10)
+    crass (1.0.6)
+    digest (3.1.0)
+    erubi (1.10.0)
+    globalid (1.0.0)
+      activesupport (>= 5.0)
+    i18n (1.10.0)
       concurrent-ruby (~> 1.0)
-    kramdown (2.3.0)
+    kramdown (2.4.0)
       rexml
     kramdown-parser-gfm (1.1.0)
       kramdown (~> 2.0)
-    loofah (2.2.3)
+    loofah (2.18.0)
       crass (~> 1.0.2)
       nokogiri (>= 1.5.9)
-    m (1.5.1)
+    m (1.6.0)
       method_source (>= 0.6.7)
       rake (>= 0.9.2.2)
     mail (2.7.1)
       mini_mime (>= 0.1.1)
     marcel (0.3.3)
       mimemagic (~> 0.3.2)
-    method_source (0.9.2)
-    mimemagic (0.3.3)
-    mini_mime (1.0.1)
-    mini_portile2 (2.4.0)
-    minitest (5.11.3)
-    nio4r (2.3.1)
-    nokogiri (1.10.3)
-      mini_portile2 (~> 2.4.0)
-    rack (2.0.7)
+    method_source (1.0.0)
+    mimemagic (0.3.10)
+      nokogiri (~> 1)
+      rake
+    mini_mime (1.1.2)
+    minitest (5.15.0)
+    net-protocol (0.1.3)
+      timeout
+    net-smtp (0.3.1)
+      digest
+      net-protocol
+      timeout
+    nio4r (2.5.8)
+    nokogiri (1.13.6-x86_64-darwin)
+      racc (~> 1.4)
+    nokogiri (1.13.6-x86_64-linux)
+      racc (~> 1.4)
+    racc (1.6.0)
+    rack (2.2.3.1)
     rack-test (1.1.0)
       rack (>= 1.0, < 3)
     rails (5.2.3)
@@ -103,43 +114,46 @@ GEM
     rails-dom-testing (2.0.3)
       activesupport (>= 4.2.0)
       nokogiri (>= 1.6)
-    rails-html-sanitizer (1.0.4)
-      loofah (~> 2.2, >= 2.2.2)
+    rails-html-sanitizer (1.4.3)
+      loofah (~> 2.3)
     railties (5.2.3)
       actionpack (= 5.2.3)
       activesupport (= 5.2.3)
       method_source
       rake (>= 0.8.7)
       thor (>= 0.19.0, < 2.0)
-    rake (12.3.2)
-    rexml (3.2.4)
-    sprockets (3.7.2)
+    rake (13.0.6)
+    rexml (3.2.5)
+    sprockets (4.0.3)
       concurrent-ruby (~> 1.0)
       rack (> 1, < 3)
-    sprockets-rails (3.2.1)
-      actionpack (>= 4.0)
-      activesupport (>= 4.0)
+    sprockets-rails (3.4.2)
+      actionpack (>= 5.2)
+      activesupport (>= 5.2)
       sprockets (>= 3.0.0)
-    sqlite3 (1.3.13)
-    thor (0.20.3)
+    sqlite3 (1.4.2)
+    thor (1.2.1)
     thread_safe (0.3.6)
-    tzinfo (1.2.5)
+    timeout (0.3.0)
+    tzinfo (1.2.9)
       thread_safe (~> 0.1)
-    websocket-driver (0.7.0)
+    websocket-driver (0.7.5)
       websocket-extensions (>= 0.1.0)
-    websocket-extensions (0.1.3)
+    websocket-extensions (0.1.5)
 
 PLATFORMS
-  ruby
+  x86_64-darwin-20
+  x86_64-linux
 
 DEPENDENCIES
   appraisal
   m
   maildown!
+  net-smtp
   rails (= 5.2.3)
   railties
   rake
-  sqlite3 (~> 1.3.6)
+  sqlite3 (~> 1.4)
 
 BUNDLED WITH
-   2.1.4
+   2.3.15
diff --git a/gemfiles/rails_6.gemfile.lock b/gemfiles/rails_6.gemfile.lock
deleted file mode 100644
index b5a73f4..0000000
--- a/gemfiles/rails_6.gemfile.lock
+++ /dev/null
@@ -1,161 +0,0 @@
-PATH
-  remote: ..
-  specs:
-    maildown (3.2.0)
-      actionmailer (>= 4.0.0)
-      kramdown-parser-gfm
-
-GEM
-  remote: https://rubygems.org/
-  specs:
-    actioncable (6.0.0)
-      actionpack (= 6.0.0)
-      nio4r (~> 2.0)
-      websocket-driver (>= 0.6.1)
-    actionmailbox (6.0.0)
-      actionpack (= 6.0.0)
-      activejob (= 6.0.0)
-      activerecord (= 6.0.0)
-      activestorage (= 6.0.0)
-      activesupport (= 6.0.0)
-      mail (>= 2.7.1)
-    actionmailer (6.0.0)
-      actionpack (= 6.0.0)
-      actionview (= 6.0.0)
-      activejob (= 6.0.0)
-      mail (~> 2.5, >= 2.5.4)
-      rails-dom-testing (~> 2.0)
-    actionpack (6.0.0)
-      actionview (= 6.0.0)
-      activesupport (= 6.0.0)
-      rack (~> 2.0)
-      rack-test (>= 0.6.3)
-      rails-dom-testing (~> 2.0)
-      rails-html-sanitizer (~> 1.0, >= 1.2.0)
-    actiontext (6.0.0)
-      actionpack (= 6.0.0)
-      activerecord (= 6.0.0)
-      activestorage (= 6.0.0)
-      activesupport (= 6.0.0)
-      nokogiri (>= 1.8.5)
-    actionview (6.0.0)
-      activesupport (= 6.0.0)
-      builder (~> 3.1)
-      erubi (~> 1.4)
-      rails-dom-testing (~> 2.0)
-      rails-html-sanitizer (~> 1.1, >= 1.2.0)
-    activejob (6.0.0)
-      activesupport (= 6.0.0)
-      globalid (>= 0.3.6)
-    activemodel (6.0.0)
-      activesupport (= 6.0.0)
-    activerecord (6.0.0)
-      activemodel (= 6.0.0)
-      activesupport (= 6.0.0)
-    activestorage (6.0.0)
-      actionpack (= 6.0.0)
-      activejob (= 6.0.0)
-      activerecord (= 6.0.0)
-      marcel (~> 0.3.1)
-    activesupport (6.0.0)
-      concurrent-ruby (~> 1.0, >= 1.0.2)
-      i18n (>= 0.7, < 2)
-      minitest (~> 5.1)
-      tzinfo (~> 1.1)
-      zeitwerk (~> 2.1, >= 2.1.8)
-    appraisal (2.2.0)
-      bundler
-      rake
-      thor (>= 0.14.0)
-    builder (3.2.3)
-    concurrent-ruby (1.1.5)
-    crass (1.0.4)
-    erubi (1.9.0)
-    globalid (0.4.2)
-      activesupport (>= 4.2.0)
-    i18n (1.6.0)
-      concurrent-ruby (~> 1.0)
-    kramdown (2.3.0)
-      rexml
-    kramdown-parser-gfm (1.1.0)
-      kramdown (~> 2.0)
-    loofah (2.3.0)
-      crass (~> 1.0.2)
-      nokogiri (>= 1.5.9)
-    m (1.5.1)
-      method_source (>= 0.6.7)
-      rake (>= 0.9.2.2)
-    mail (2.7.1)
-      mini_mime (>= 0.1.1)
-    marcel (0.3.3)
-      mimemagic (~> 0.3.2)
-    method_source (0.9.2)
-    mimemagic (0.3.3)
-    mini_mime (1.0.2)
-    mini_portile2 (2.4.0)
-    minitest (5.12.2)
-    nio4r (2.5.2)
-    nokogiri (1.10.4)
-      mini_portile2 (~> 2.4.0)
-    rack (2.0.7)
-    rack-test (1.1.0)
-      rack (>= 1.0, < 3)
-    rails (6.0.0)
-      actioncable (= 6.0.0)
-      actionmailbox (= 6.0.0)
-      actionmailer (= 6.0.0)
-      actionpack (= 6.0.0)
-      actiontext (= 6.0.0)
-      actionview (= 6.0.0)
-      activejob (= 6.0.0)
-      activemodel (= 6.0.0)
-      activerecord (= 6.0.0)
-      activestorage (= 6.0.0)
-      activesupport (= 6.0.0)
-      bundler (>= 1.3.0)
-      railties (= 6.0.0)
-      sprockets-rails (>= 2.0.0)
-    rails-dom-testing (2.0.3)
-      activesupport (>= 4.2.0)
-      nokogiri (>= 1.6)
-    rails-html-sanitizer (1.2.0)
-      loofah (~> 2.2, >= 2.2.2)
-    railties (6.0.0)
-      actionpack (= 6.0.0)
-      activesupport (= 6.0.0)
-      method_source
-      rake (>= 0.8.7)
-      thor (>= 0.20.3, < 2.0)
-    rake (13.0.0)
-    rexml (3.2.4)
-    sprockets (3.7.2)
-      concurrent-ruby (~> 1.0)
-      rack (> 1, < 3)
-    sprockets-rails (3.2.1)
-      actionpack (>= 4.0)
-      activesupport (>= 4.0)
-      sprockets (>= 3.0.0)
-    sqlite3 (1.4.1)
-    thor (0.20.3)
-    thread_safe (0.3.6)
-    tzinfo (1.2.5)
-      thread_safe (~> 0.1)
-    websocket-driver (0.7.1)
-      websocket-extensions (>= 0.1.0)
-    websocket-extensions (0.1.4)
-    zeitwerk (2.1.10)
-
-PLATFORMS
-  ruby
-
-DEPENDENCIES
-  appraisal
-  m
-  maildown!
-  rails (= 6.0.0)
-  railties
-  rake
-  sqlite3 (~> 1.4)
-
-BUNDLED WITH
-   2.1.4
diff --git a/gemfiles/rails_5.gemfile b/gemfiles/rails_6_0.gemfile
similarity index 58%
rename from gemfiles/rails_5.gemfile
rename to gemfiles/rails_6_0.gemfile
index 5c49817..b131fc3 100644
--- a/gemfiles/rails_5.gemfile
+++ b/gemfiles/rails_6_0.gemfile
@@ -3,7 +3,8 @@
 source "https://rubygems.org"
 
 gem "appraisal"
-gem "rails", "5.0.7.2"
-gem "sqlite3", "~> 1.3.6"
+gem "rails", "6.0.5"
+gem "sqlite3", "~> 1.4"
+gem "net-smtp", require: false
 
 gemspec path: "../"
diff --git a/gemfiles/rails_6_0.gemfile.lock b/gemfiles/rails_6_0.gemfile.lock
new file mode 100644
index 0000000..ac28527
--- /dev/null
+++ b/gemfiles/rails_6_0.gemfile.lock
@@ -0,0 +1,171 @@
+PATH
+  remote: ..
+  specs:
+    maildown (3.3.0)
+      actionmailer (>= 4.0.0)
+      kramdown-parser-gfm
+
+GEM
+  remote: https://rubygems.org/
+  specs:
+    actioncable (6.0.5)
+      actionpack (= 6.0.5)
+      nio4r (~> 2.0)
+      websocket-driver (>= 0.6.1)
+    actionmailbox (6.0.5)
+      actionpack (= 6.0.5)
+      activejob (= 6.0.5)
+      activerecord (= 6.0.5)
+      activestorage (= 6.0.5)
+      activesupport (= 6.0.5)
+      mail (>= 2.7.1)
+    actionmailer (6.0.5)
+      actionpack (= 6.0.5)
+      actionview (= 6.0.5)
+      activejob (= 6.0.5)
+      mail (~> 2.5, >= 2.5.4)
+      rails-dom-testing (~> 2.0)
+    actionpack (6.0.5)
+      actionview (= 6.0.5)
+      activesupport (= 6.0.5)
+      rack (~> 2.0, >= 2.0.8)
+      rack-test (>= 0.6.3)
+      rails-dom-testing (~> 2.0)
+      rails-html-sanitizer (~> 1.0, >= 1.2.0)
+    actiontext (6.0.5)
+      actionpack (= 6.0.5)
+      activerecord (= 6.0.5)
+      activestorage (= 6.0.5)
+      activesupport (= 6.0.5)
+      nokogiri (>= 1.8.5)
+    actionview (6.0.5)
+      activesupport (= 6.0.5)
+      builder (~> 3.1)
+      erubi (~> 1.4)
+      rails-dom-testing (~> 2.0)
+      rails-html-sanitizer (~> 1.1, >= 1.2.0)
+    activejob (6.0.5)
+      activesupport (= 6.0.5)
+      globalid (>= 0.3.6)
+    activemodel (6.0.5)
+      activesupport (= 6.0.5)
+    activerecord (6.0.5)
+      activemodel (= 6.0.5)
+      activesupport (= 6.0.5)
+    activestorage (6.0.5)
+      actionpack (= 6.0.5)
+      activejob (= 6.0.5)
+      activerecord (= 6.0.5)
+      marcel (~> 1.0)
+    activesupport (6.0.5)
+      concurrent-ruby (~> 1.0, >= 1.0.2)
+      i18n (>= 0.7, < 2)
+      minitest (~> 5.1)
+      tzinfo (~> 1.1)
+      zeitwerk (~> 2.2, >= 2.2.2)
+    appraisal (2.4.1)
+      bundler
+      rake
+      thor (>= 0.14.0)
+    builder (3.2.4)
+    concurrent-ruby (1.1.10)
+    crass (1.0.6)
+    digest (3.1.0)
+    erubi (1.10.0)
+    globalid (1.0.0)
+      activesupport (>= 5.0)
+    i18n (1.10.0)
+      concurrent-ruby (~> 1.0)
+    kramdown (2.4.0)
+      rexml
+    kramdown-parser-gfm (1.1.0)
+      kramdown (~> 2.0)
+    loofah (2.18.0)
+      crass (~> 1.0.2)
+      nokogiri (>= 1.5.9)
+    m (1.6.0)
+      method_source (>= 0.6.7)
+      rake (>= 0.9.2.2)
+    mail (2.7.1)
+      mini_mime (>= 0.1.1)
+    marcel (1.0.2)
+    method_source (1.0.0)
+    mini_mime (1.1.2)
+    minitest (5.15.0)
+    net-protocol (0.1.3)
+      timeout
+    net-smtp (0.3.1)
+      digest
+      net-protocol
+      timeout
+    nio4r (2.5.8)
+    nokogiri (1.13.6-x86_64-darwin)
+      racc (~> 1.4)
+    nokogiri (1.13.6-x86_64-linux)
+      racc (~> 1.4)
+    racc (1.6.0)
+    rack (2.2.3.1)
+    rack-test (1.1.0)
+      rack (>= 1.0, < 3)
+    rails (6.0.5)
+      actioncable (= 6.0.5)
+      actionmailbox (= 6.0.5)
+      actionmailer (= 6.0.5)
+      actionpack (= 6.0.5)
+      actiontext (= 6.0.5)
+      actionview (= 6.0.5)
+      activejob (= 6.0.5)
+      activemodel (= 6.0.5)
+      activerecord (= 6.0.5)
+      activestorage (= 6.0.5)
+      activesupport (= 6.0.5)
+      bundler (>= 1.3.0)
+      railties (= 6.0.5)
+      sprockets-rails (>= 2.0.0)
+    rails-dom-testing (2.0.3)
+      activesupport (>= 4.2.0)
+      nokogiri (>= 1.6)
+    rails-html-sanitizer (1.4.3)
+      loofah (~> 2.3)
+    railties (6.0.5)
+      actionpack (= 6.0.5)
+      activesupport (= 6.0.5)
+      method_source
+      rake (>= 0.8.7)
+      thor (>= 0.20.3, < 2.0)
+    rake (13.0.6)
+    rexml (3.2.5)
+    sprockets (4.0.3)
+      concurrent-ruby (~> 1.0)
+      rack (> 1, < 3)
+    sprockets-rails (3.4.2)
+      actionpack (>= 5.2)
+      activesupport (>= 5.2)
+      sprockets (>= 3.0.0)
+    sqlite3 (1.4.2)
+    thor (1.2.1)
+    thread_safe (0.3.6)
+    timeout (0.3.0)
+    tzinfo (1.2.9)
+      thread_safe (~> 0.1)
+    websocket-driver (0.7.5)
+      websocket-extensions (>= 0.1.0)
+    websocket-extensions (0.1.5)
+    zeitwerk (2.5.4)
+
+PLATFORMS
+  x86_64-darwin-20
+  x86_64-linux
+
+DEPENDENCIES
+  appraisal
+  m
+  maildown!
+  net-smtp
+  rails (= 6.0.5)
+  railties
+  rake
+  sqlite3 (~> 1.4)
+
+BUNDLED WITH
+   2.3.15
diff --git a/gemfiles/rails_51.gemfile b/gemfiles/rails_6_1.gemfile
similarity index 58%
rename from gemfiles/rails_51.gemfile
rename to gemfiles/rails_6_1.gemfile
index 298664d..db67f39 100644
--- a/gemfiles/rails_51.gemfile
+++ b/gemfiles/rails_6_1.gemfile
@@ -3,7 +3,8 @@
 source "https://rubygems.org"
 
 gem "appraisal"
-gem "rails", "5.1.7"
-gem "sqlite3", "~> 1.3.6"
+gem "rails", "6.1.6"
+gem "sqlite3", "~> 1.4"
+gem "net-smtp", require: false
 
 gemspec path: "../"
diff --git a/gemfiles/rails_6_1.gemfile.lock b/gemfiles/rails_6_1.gemfile.lock
new file mode 100644
index 0000000..f081359
--- /dev/null
+++ b/gemfiles/rails_6_1.gemfile.lock
@@ -0,0 +1,174 @@
+PATH
+  remote: ..
+  specs:
+    maildown (3.3.0)
+      actionmailer (>= 4.0.0)
+      kramdown-parser-gfm
+
+GEM
+  remote: https://rubygems.org/
+  specs:
+    actioncable (6.1.6)
+      actionpack (= 6.1.6)
+      activesupport (= 6.1.6)
+      nio4r (~> 2.0)
+      websocket-driver (>= 0.6.1)
+    actionmailbox (6.1.6)
+      actionpack (= 6.1.6)
+      activejob (= 6.1.6)
+      activerecord (= 6.1.6)
+      activestorage (= 6.1.6)
+      activesupport (= 6.1.6)
+      mail (>= 2.7.1)
+    actionmailer (6.1.6)
+      actionpack (= 6.1.6)
+      actionview (= 6.1.6)
+      activejob (= 6.1.6)
+      activesupport (= 6.1.6)
+      mail (~> 2.5, >= 2.5.4)
+      rails-dom-testing (~> 2.0)
+    actionpack (6.1.6)
+      actionview (= 6.1.6)
+      activesupport (= 6.1.6)
+      rack (~> 2.0, >= 2.0.9)
+      rack-test (>= 0.6.3)
+      rails-dom-testing (~> 2.0)
+      rails-html-sanitizer (~> 1.0, >= 1.2.0)
+    actiontext (6.1.6)
+      actionpack (= 6.1.6)
+      activerecord (= 6.1.6)
+      activestorage (= 6.1.6)
+      activesupport (= 6.1.6)
+      nokogiri (>= 1.8.5)
+    actionview (6.1.6)
+      activesupport (= 6.1.6)
+      builder (~> 3.1)
+      erubi (~> 1.4)
+      rails-dom-testing (~> 2.0)
+      rails-html-sanitizer (~> 1.1, >= 1.2.0)
+    activejob (6.1.6)
+      activesupport (= 6.1.6)
+      globalid (>= 0.3.6)
+    activemodel (6.1.6)
+      activesupport (= 6.1.6)
+    activerecord (6.1.6)
+      activemodel (= 6.1.6)
+      activesupport (= 6.1.6)
+    activestorage (6.1.6)
+      actionpack (= 6.1.6)
+      activejob (= 6.1.6)
+      activerecord (= 6.1.6)
+      activesupport (= 6.1.6)
+      marcel (~> 1.0)
+      mini_mime (>= 1.1.0)
+    activesupport (6.1.6)
+      concurrent-ruby (~> 1.0, >= 1.0.2)
+      i18n (>= 1.6, < 2)
+      minitest (>= 5.1)
+      tzinfo (~> 2.0)
+      zeitwerk (~> 2.3)
+    appraisal (2.4.1)
+      bundler
+      rake
+      thor (>= 0.14.0)
+    builder (3.2.4)
+    concurrent-ruby (1.1.10)
+    crass (1.0.6)
+    digest (3.1.0)
+    erubi (1.10.0)
+    globalid (1.0.0)
+      activesupport (>= 5.0)
+    i18n (1.10.0)
+      concurrent-ruby (~> 1.0)
+    kramdown (2.4.0)
+      rexml
+    kramdown-parser-gfm (1.1.0)
+      kramdown (~> 2.0)
+    loofah (2.18.0)
+      crass (~> 1.0.2)
+      nokogiri (>= 1.5.9)
+    m (1.6.0)
+      method_source (>= 0.6.7)
+      rake (>= 0.9.2.2)
+    mail (2.7.1)
+      mini_mime (>= 0.1.1)
+    marcel (1.0.2)
+    method_source (1.0.0)
+    mini_mime (1.1.2)
+    minitest (5.15.0)
+    net-protocol (0.1.3)
+      timeout
+    net-smtp (0.3.1)
+      digest
+      net-protocol
+      timeout
+    nio4r (2.5.8)
+    nokogiri (1.13.6-x86_64-darwin)
+      racc (~> 1.4)
+    nokogiri (1.13.6-x86_64-linux)
+      racc (~> 1.4)
+    racc (1.6.0)
+    rack (2.2.3.1)
+    rack-test (1.1.0)
+      rack (>= 1.0, < 3)
+    rails (6.1.6)
+      actioncable (= 6.1.6)
+      actionmailbox (= 6.1.6)
+      actionmailer (= 6.1.6)
+      actionpack (= 6.1.6)
+      actiontext (= 6.1.6)
+      actionview (= 6.1.6)
+      activejob (= 6.1.6)
+      activemodel (= 6.1.6)
+      activerecord (= 6.1.6)
+      activestorage (= 6.1.6)
+      activesupport (= 6.1.6)
+      bundler (>= 1.15.0)
+      railties (= 6.1.6)
+      sprockets-rails (>= 2.0.0)
+    rails-dom-testing (2.0.3)
+      activesupport (>= 4.2.0)
+      nokogiri (>= 1.6)
+    rails-html-sanitizer (1.4.3)
+      loofah (~> 2.3)
+    railties (6.1.6)
+      actionpack (= 6.1.6)
+      activesupport (= 6.1.6)
+      method_source
+      rake (>= 12.2)
+      thor (~> 1.0)
+    rake (13.0.6)
+    rexml (3.2.5)
+    sprockets (4.0.3)
+      concurrent-ruby (~> 1.0)
+      rack (> 1, < 3)
+    sprockets-rails (3.4.2)
+      actionpack (>= 5.2)
+      activesupport (>= 5.2)
+      sprockets (>= 3.0.0)
+    sqlite3 (1.4.2)
+    thor (1.2.1)
+    timeout (0.3.0)
+    tzinfo (2.0.4)
+      concurrent-ruby (~> 1.0)
+    websocket-driver (0.7.5)
+      websocket-extensions (>= 0.1.0)
+    websocket-extensions (0.1.5)
+    zeitwerk (2.5.4)
+
+PLATFORMS
+  x86_64-darwin-20
+  x86_64-linux
+
+DEPENDENCIES
+  appraisal
+  m
+  maildown!
+  net-smtp
+  rails (= 6.1.6)
+  railties
+  rake
+  sqlite3 (~> 1.4)
+
+BUNDLED WITH
+   2.3.15
diff --git a/gemfiles/rails_6.gemfile b/gemfiles/rails_7_0.gemfile
similarity index 86%
rename from gemfiles/rails_6.gemfile
rename to gemfiles/rails_7_0.gemfile
index 3de0970..28ad8cf 100644
--- a/gemfiles/rails_6.gemfile
+++ b/gemfiles/rails_7_0.gemfile
@@ -3,7 +3,7 @@
 source "https://rubygems.org"
 
 gem "appraisal"
-gem "rails", "6.0.0"
+gem "rails", "7.0.3"
 gem "sqlite3", "~> 1.4"
 
 gemspec path: "../"
diff --git a/gemfiles/rails_7_0.gemfile.lock b/gemfiles/rails_7_0.gemfile.lock
new file mode 100644
index 0000000..a67e56e
--- /dev/null
+++ b/gemfiles/rails_7_0.gemfile.lock
@@ -0,0 +1,181 @@
+PATH
+  remote: ..
+  specs:
+    maildown (3.3.0)
+      actionmailer (>= 4.0.0)
+      kramdown-parser-gfm
+
+GEM
+  remote: https://rubygems.org/
+  specs:
+    actioncable (7.0.3)
+      actionpack (= 7.0.3)
+      activesupport (= 7.0.3)
+      nio4r (~> 2.0)
+      websocket-driver (>= 0.6.1)
+    actionmailbox (7.0.3)
+      actionpack (= 7.0.3)
+      activejob (= 7.0.3)
+      activerecord (= 7.0.3)
+      activestorage (= 7.0.3)
+      activesupport (= 7.0.3)
+      mail (>= 2.7.1)
+      net-imap
+      net-pop
+      net-smtp
+    actionmailer (7.0.3)
+      actionpack (= 7.0.3)
+      actionview (= 7.0.3)
+      activejob (= 7.0.3)
+      activesupport (= 7.0.3)
+      mail (~> 2.5, >= 2.5.4)
+      net-imap
+      net-pop
+      net-smtp
+      rails-dom-testing (~> 2.0)
+    actionpack (7.0.3)
+      actionview (= 7.0.3)
+      activesupport (= 7.0.3)
+      rack (~> 2.0, >= 2.2.0)
+      rack-test (>= 0.6.3)
+      rails-dom-testing (~> 2.0)
+      rails-html-sanitizer (~> 1.0, >= 1.2.0)
+    actiontext (7.0.3)
+      actionpack (= 7.0.3)
+      activerecord (= 7.0.3)
+      activestorage (= 7.0.3)
+      activesupport (= 7.0.3)
+      globalid (>= 0.6.0)
+      nokogiri (>= 1.8.5)
+    actionview (7.0.3)
+      activesupport (= 7.0.3)
+      builder (~> 3.1)
+      erubi (~> 1.4)
+      rails-dom-testing (~> 2.0)
+      rails-html-sanitizer (~> 1.1, >= 1.2.0)
+    activejob (7.0.3)
+      activesupport (= 7.0.3)
+      globalid (>= 0.3.6)
+    activemodel (7.0.3)
+      activesupport (= 7.0.3)
+    activerecord (7.0.3)
+      activemodel (= 7.0.3)
+      activesupport (= 7.0.3)
+    activestorage (7.0.3)
+      actionpack (= 7.0.3)
+      activejob (= 7.0.3)
+      activerecord (= 7.0.3)
+      activesupport (= 7.0.3)
+      marcel (~> 1.0)
+      mini_mime (>= 1.1.0)
+    activesupport (7.0.3)
+      concurrent-ruby (~> 1.0, >= 1.0.2)
+      i18n (>= 1.6, < 2)
+      minitest (>= 5.1)
+      tzinfo (~> 2.0)
+    appraisal (2.4.1)
+      bundler
+      rake
+      thor (>= 0.14.0)
+    builder (3.2.4)
+    concurrent-ruby (1.1.10)
+    crass (1.0.6)
+    digest (3.1.0)
+    erubi (1.10.0)
+    globalid (1.0.0)
+      activesupport (>= 5.0)
+    i18n (1.10.0)
+      concurrent-ruby (~> 1.0)
+    kramdown (2.4.0)
+      rexml
+    kramdown-parser-gfm (1.1.0)
+      kramdown (~> 2.0)
+    loofah (2.18.0)
+      crass (~> 1.0.2)
+      nokogiri (>= 1.5.9)
+    m (1.6.0)
+      method_source (>= 0.6.7)
+      rake (>= 0.9.2.2)
+    mail (2.7.1)
+      mini_mime (>= 0.1.1)
+    marcel (1.0.2)
+    method_source (1.0.0)
+    mini_mime (1.1.2)
+    minitest (5.15.0)
+    net-imap (0.2.3)
+      digest
+      net-protocol
+      strscan
+    net-pop (0.1.1)
+      digest
+      net-protocol
+      timeout
+    net-protocol (0.1.3)
+      timeout
+    net-smtp (0.3.1)
+      digest
+      net-protocol
+      timeout
+    nio4r (2.5.8)
+    nokogiri (1.13.6-x86_64-darwin)
+      racc (~> 1.4)
+    nokogiri (1.13.6-x86_64-linux)
+      racc (~> 1.4)
+    racc (1.6.0)
+    rack (2.2.3.1)
+    rack-test (1.1.0)
+      rack (>= 1.0, < 3)
+    rails (7.0.3)
+      actioncable (= 7.0.3)
+      actionmailbox (= 7.0.3)
+      actionmailer (= 7.0.3)
+      actionpack (= 7.0.3)
+      actiontext (= 7.0.3)
+      actionview (= 7.0.3)
+      activejob (= 7.0.3)
+      activemodel (= 7.0.3)
+      activerecord (= 7.0.3)
+      activestorage (= 7.0.3)
+      activesupport (= 7.0.3)
+      bundler (>= 1.15.0)
+      railties (= 7.0.3)
+    rails-dom-testing (2.0.3)
+      activesupport (>= 4.2.0)
+      nokogiri (>= 1.6)
+    rails-html-sanitizer (1.4.3)
+      loofah (~> 2.3)
+    railties (7.0.3)
+      actionpack (= 7.0.3)
+      activesupport (= 7.0.3)
+      method_source
+      rake (>= 12.2)
+      thor (~> 1.0)
+      zeitwerk (~> 2.5)
+    rake (13.0.6)
+    rexml (3.2.5)
+    sqlite3 (1.4.2)
+    strscan (3.0.3)
+    thor (1.2.1)
+    timeout (0.3.0)
+    tzinfo (2.0.4)
+      concurrent-ruby (~> 1.0)
+    websocket-driver (0.7.5)
+      websocket-extensions (>= 0.1.0)
+    websocket-extensions (0.1.5)
+    zeitwerk (2.5.4)
+
+PLATFORMS
+  x86_64-darwin-20
+  x86_64-linux
+
+DEPENDENCIES
+  appraisal
+  m
+  maildown!
+  rails (= 7.0.3)
+  railties
+  rake
+  sqlite3 (~> 1.4)
+
+BUNDLED WITH
+   2.3.15
diff --git a/gemfiles/rails_head.gemfile b/gemfiles/rails_head.gemfile
index 3355b74..ee70e62 100644
--- a/gemfiles/rails_head.gemfile
+++ b/gemfiles/rails_head.gemfile
@@ -4,6 +4,7 @@ source "https://rubygems.org"
 
 gem "appraisal"
 gem "rails", git: "https://github.com/rails/rails.git"
+gem "railties", git: "https://github.com/rails/rails.git"
 gem "sqlite3", "~> 1.4"
 
 gemspec path: "../"
diff --git a/gemfiles/rails_head.gemfile.lock b/gemfiles/rails_head.gemfile.lock
index 9bc5387..f3a4632 100644
--- a/gemfiles/rails_head.gemfile.lock
+++ b/gemfiles/rails_head.gemfile.lock
@@ -1,154 +1,176 @@
 GIT
   remote: https://github.com/rails/rails.git
-  revision: 85a8bc644be69908f05740a5886ec19cd3679df5
+  revision: 7c1165c8c8752a84a9d02ef06fccbf113b8ff6b0
   specs:
-    actioncable (6.1.0.alpha)
-      actionpack (= 6.1.0.alpha)
+    actioncable (7.1.0.alpha)
+      actionpack (= 7.1.0.alpha)
+      activesupport (= 7.1.0.alpha)
       nio4r (~> 2.0)
       websocket-driver (>= 0.6.1)
-    actionmailbox (6.1.0.alpha)
-      actionpack (= 6.1.0.alpha)
-      activejob (= 6.1.0.alpha)
-      activerecord (= 6.1.0.alpha)
-      activestorage (= 6.1.0.alpha)
-      activesupport (= 6.1.0.alpha)
+      zeitwerk (~> 2.5)
+    actionmailbox (7.1.0.alpha)
+      actionpack (= 7.1.0.alpha)
+      activejob (= 7.1.0.alpha)
+      activerecord (= 7.1.0.alpha)
+      activestorage (= 7.1.0.alpha)
+      activesupport (= 7.1.0.alpha)
       mail (>= 2.7.1)
-    actionmailer (6.1.0.alpha)
-      actionpack (= 6.1.0.alpha)
-      actionview (= 6.1.0.alpha)
-      activejob (= 6.1.0.alpha)
+      net-imap
+      net-pop
+      net-smtp
+    actionmailer (7.1.0.alpha)
+      actionpack (= 7.1.0.alpha)
+      actionview (= 7.1.0.alpha)
+      activejob (= 7.1.0.alpha)
+      activesupport (= 7.1.0.alpha)
       mail (~> 2.5, >= 2.5.4)
+      net-imap
+      net-pop
+      net-smtp
       rails-dom-testing (~> 2.0)
-    actionpack (6.1.0.alpha)
-      actionview (= 6.1.0.alpha)
-      activesupport (= 6.1.0.alpha)
-      rack (~> 2.0)
+    actionpack (7.1.0.alpha)
+      actionview (= 7.1.0.alpha)
+      activesupport (= 7.1.0.alpha)
+      rack (~> 2.0, >= 2.2.0)
       rack-test (>= 0.6.3)
       rails-dom-testing (~> 2.0)
-      rails-html-sanitizer (~> 1.0, >= 1.0.2)
-    actiontext (6.1.0.alpha)
-      actionpack (= 6.1.0.alpha)
-      activerecord (= 6.1.0.alpha)
-      activestorage (= 6.1.0.alpha)
-      activesupport (= 6.1.0.alpha)
+      rails-html-sanitizer (~> 1.0, >= 1.2.0)
+    actiontext (7.1.0.alpha)
+      actionpack (= 7.1.0.alpha)
+      activerecord (= 7.1.0.alpha)
+      activestorage (= 7.1.0.alpha)
+      activesupport (= 7.1.0.alpha)
+      globalid (>= 0.6.0)
       nokogiri (>= 1.8.5)
-    actionview (6.1.0.alpha)
-      activesupport (= 6.1.0.alpha)
+    actionview (7.1.0.alpha)
+      activesupport (= 7.1.0.alpha)
       builder (~> 3.1)
       erubi (~> 1.4)
       rails-dom-testing (~> 2.0)
-      rails-html-sanitizer (~> 1.0, >= 1.0.3)
-    activejob (6.1.0.alpha)
-      activesupport (= 6.1.0.alpha)
+      rails-html-sanitizer (~> 1.1, >= 1.2.0)
+    activejob (7.1.0.alpha)
+      activesupport (= 7.1.0.alpha)
       globalid (>= 0.3.6)
-    activemodel (6.1.0.alpha)
-      activesupport (= 6.1.0.alpha)
-    activerecord (6.1.0.alpha)
-      activemodel (= 6.1.0.alpha)
-      activesupport (= 6.1.0.alpha)
-    activestorage (6.1.0.alpha)
-      actionpack (= 6.1.0.alpha)
-      activejob (= 6.1.0.alpha)
-      activerecord (= 6.1.0.alpha)
-      marcel (~> 0.3.1)
-    activesupport (6.1.0.alpha)
+    activemodel (7.1.0.alpha)
+      activesupport (= 7.1.0.alpha)
+    activerecord (7.1.0.alpha)
+      activemodel (= 7.1.0.alpha)
+      activesupport (= 7.1.0.alpha)
+    activestorage (7.1.0.alpha)
+      actionpack (= 7.1.0.alpha)
+      activejob (= 7.1.0.alpha)
+      activerecord (= 7.1.0.alpha)
+      activesupport (= 7.1.0.alpha)
+      marcel (~> 1.0)
+      mini_mime (>= 1.1.0)
+    activesupport (7.1.0.alpha)
       concurrent-ruby (~> 1.0, >= 1.0.2)
-      i18n (>= 0.7, < 2)
-      minitest (~> 5.1)
-      tzinfo (~> 1.1)
-      zeitwerk (~> 2.1, >= 2.1.4)
-    rails (6.1.0.alpha)
-      actioncable (= 6.1.0.alpha)
-      actionmailbox (= 6.1.0.alpha)
-      actionmailer (= 6.1.0.alpha)
-      actionpack (= 6.1.0.alpha)
-      actiontext (= 6.1.0.alpha)
-      actionview (= 6.1.0.alpha)
-      activejob (= 6.1.0.alpha)
-      activemodel (= 6.1.0.alpha)
-      activerecord (= 6.1.0.alpha)
-      activestorage (= 6.1.0.alpha)
-      activesupport (= 6.1.0.alpha)
-      bundler (>= 1.3.0)
-      railties (= 6.1.0.alpha)
-      sprockets-rails (>= 2.0.0)
-    railties (6.1.0.alpha)
-      actionpack (= 6.1.0.alpha)
-      activesupport (= 6.1.0.alpha)
+      connection_pool (>= 2.2.5)
+      i18n (>= 1.6, < 2)
+      minitest (>= 5.1)
+      tzinfo (~> 2.0)
+    rails (7.1.0.alpha)
+      actioncable (= 7.1.0.alpha)
+      actionmailbox (= 7.1.0.alpha)
+      actionmailer (= 7.1.0.alpha)
+      actionpack (= 7.1.0.alpha)
+      actiontext (= 7.1.0.alpha)
+      actionview (= 7.1.0.alpha)
+      activejob (= 7.1.0.alpha)
+      activemodel (= 7.1.0.alpha)
+      activerecord (= 7.1.0.alpha)
+      activestorage (= 7.1.0.alpha)
+      activesupport (= 7.1.0.alpha)
+      bundler (>= 1.15.0)
+      railties (= 7.1.0.alpha)
+    railties (7.1.0.alpha)
+      actionpack (= 7.1.0.alpha)
+      activesupport (= 7.1.0.alpha)
       method_source
-      rake (>= 0.8.7)
-      thor (>= 0.20.3, < 2.0)
+      rake (>= 12.2)
+      thor (~> 1.0)
+      zeitwerk (~> 2.5)
 
 PATH
   remote: ..
   specs:
-    maildown (3.2.0)
+    maildown (3.3.0)
       actionmailer (>= 4.0.0)
       kramdown-parser-gfm
 
 GEM
   remote: https://rubygems.org/
   specs:
-    appraisal (2.2.0)
+    appraisal (2.4.1)
       bundler
       rake
       thor (>= 0.14.0)
-    builder (3.2.3)
-    concurrent-ruby (1.1.5)
-    crass (1.0.4)
-    erubi (1.8.0)
-    globalid (0.4.2)
-      activesupport (>= 4.2.0)
-    i18n (1.6.0)
+    builder (3.2.4)
+    concurrent-ruby (1.1.10)
+    connection_pool (2.2.5)
+    crass (1.0.6)
+    digest (3.1.0)
+    erubi (1.10.0)
+    globalid (1.0.0)
+      activesupport (>= 5.0)
+    i18n (1.10.0)
       concurrent-ruby (~> 1.0)
-    kramdown (2.3.0)
+    kramdown (2.4.0)
       rexml
     kramdown-parser-gfm (1.1.0)
       kramdown (~> 2.0)
-    loofah (2.2.3)
+    loofah (2.18.0)
       crass (~> 1.0.2)
       nokogiri (>= 1.5.9)
-    m (1.5.1)
+    m (1.6.0)
       method_source (>= 0.6.7)
       rake (>= 0.9.2.2)
     mail (2.7.1)
       mini_mime (>= 0.1.1)
-    marcel (0.3.3)
-      mimemagic (~> 0.3.2)
-    method_source (0.9.2)
-    mimemagic (0.3.3)
-    mini_mime (1.0.1)
-    mini_portile2 (2.4.0)
-    minitest (5.11.3)
-    nio4r (2.3.1)
-    nokogiri (1.10.3)
-      mini_portile2 (~> 2.4.0)
-    rack (2.0.7)
+    marcel (1.0.2)
+    method_source (1.0.0)
+    mini_mime (1.1.2)
+    mini_portile2 (2.8.0)
+    minitest (5.15.0)
+    net-imap (0.2.3)
+      digest
+      net-protocol
+      strscan
+    net-pop (0.1.1)
+      digest
+      net-protocol
+      timeout
+    net-protocol (0.1.3)
+      timeout
+    net-smtp (0.3.1)
+      digest
+      net-protocol
+      timeout
+    nio4r (2.5.8)
+    nokogiri (1.13.6)
+      mini_portile2 (~> 2.8.0)
+      racc (~> 1.4)
+    racc (1.6.0)
+    rack (2.2.3.1)
     rack-test (1.1.0)
       rack (>= 1.0, < 3)
     rails-dom-testing (2.0.3)
       activesupport (>= 4.2.0)
       nokogiri (>= 1.6)
-    rails-html-sanitizer (1.0.4)
-      loofah (~> 2.2, >= 2.2.2)
-    rake (12.3.2)
-    rexml (3.2.4)
-    sprockets (3.7.2)
+    rails-html-sanitizer (1.4.3)
+      loofah (~> 2.3)
+    rake (13.0.6)
+    rexml (3.2.5)
+    sqlite3 (1.4.2)
+    strscan (3.0.3)
+    thor (1.2.1)
+    timeout (0.3.0)
+    tzinfo (2.0.4)
       concurrent-ruby (~> 1.0)
-      rack (> 1, < 3)
-    sprockets-rails (3.2.1)
-      actionpack (>= 4.0)
-      activesupport (>= 4.0)
-      sprockets (>= 3.0.0)
-    sqlite3 (1.4.1)
-    thor (0.20.3)
-    thread_safe (0.3.6)
-    tzinfo (1.2.5)
-      thread_safe (~> 0.1)
-    websocket-driver (0.7.0)
+    websocket-driver (0.7.5)
       websocket-extensions (>= 0.1.0)
-    websocket-extensions (0.1.3)
-    zeitwerk (2.1.6)
+    websocket-extensions (0.1.5)
+    zeitwerk (2.5.4)
 
 PLATFORMS
   ruby
@@ -158,9 +180,9 @@ DEPENDENCIES
   m
   maildown!
   rails!
-  railties
+  railties!
   rake
   sqlite3 (~> 1.4)
 
 BUNDLED WITH
-   2.1.4
+   2.3.15
diff --git a/lib/maildown/ext/action_view.rb b/lib/maildown/ext/action_view.rb
index 9d680ee..375e2ab 100644
--- a/lib/maildown/ext/action_view.rb
+++ b/lib/maildown/ext/action_view.rb
@@ -1,5 +1,20 @@
 # frozen_string_literal: true
 
+if !defined?(ActionView::OptimizedFileSystemResolver)
+  module ActionView
+    # https://github.com/codetriage/maildown/issues/59
+    #
+    # extract_handler_and_format_and_variant was removed in https://github.com/rails/rails/commit/2be8d3ebf85e26e936a7717b968737ee333d95bd
+    # OptimizedFileSystemResolver was removed in https://github.com/rails/rails/commit/faac734387124c6d780dbfcfdab721b2f26ce865
+    class OptimizedFileSystemResolver < FileSystemResolver
+      def extract_handler_and_format_and_variant(template)
+        details = @path_parser.parse(template)
+        [details.handler, details.format, details.variant]
+      end
+    end
+  end
+end
+
 # This monkeypatch allows the use of `.md.erb` file extensions
 # in addition to `.md+erb` and `.md`
 module ActionView
diff --git a/test/dummy/app/assets/config/manifest.js b/test/dummy/app/assets/config/manifest.js
new file mode 100644
index 0000000..6b49435
--- /dev/null
+++ b/test/dummy/app/assets/config/manifest.js
@@ -0,0 +1,2 @@
+  //= link application.css
+  //= link application.js
diff --git a/test/unit/ext_action_mailer_test.rb b/test/unit/ext_action_mailer_test.rb
index 6fd2e0b..4dc1402 100644
--- a/test/unit/ext_action_mailer_test.rb
+++ b/test/unit/ext_action_mailer_test.rb
@@ -6,9 +6,5 @@ class ExtActionMailerTest < ActiveSupport::TestCase
     monkeypatch = ActionMailer::Base.instance_method(:each_template)
     path        = monkeypatch.source_location.first
     assert_match "maildown/ext/action_mailer.rb", path
-
-    monkeypatch = ActionView::OptimizedFileSystemResolver.instance_method(:extract_handler_and_format_and_variant)
-    path        = monkeypatch.source_location.first
-    assert_match "maildown/ext/action_view.rb", path
   end
 end