diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 101416c0..1cab3623 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -10,19 +10,25 @@ permissions:
 
 jobs:
   rspec:
-    runs-on: ubuntu-20.04
+    runs-on: ubuntu-latest
     strategy:
       fail-fast: false
       matrix:
         ruby:
-          - '3.3'
-          - '3.2'
-          - '3.1'
-          - '3.0'
-          - '2.7'
-          - '2.6'
-          - '2.5'
-          - '2.4'
+          - 3.3
+          - 3.2
+          - 3.1
+        rails:
+          - 7.2
+        include:
+          # Edge
+          - { ruby: 'head', rails: 'edge', allow-fail: true }
+          # Outdated
+          - { ruby: '3.0',  rails: '7.1',  allow-fail: true }
+          - { ruby: '2.7',  rails: '7.1',  allow-fail: true }
+          - { ruby: '2.6',  rails: '6',    allow-fail: true }
+          - { ruby: '2.5',  rails: '6',    allow-fail: true }
+          - { ruby: '2.4',  rails: '5',    allow-fail: true }
 
     services:
       mongodb:
@@ -31,13 +37,13 @@ jobs:
           - 27017:27017
 
     steps:
-      - name: Checkout
-        uses: actions/checkout@v4
+      - uses: actions/checkout@v4
 
       - name: Setup Ruby
         uses: ruby/setup-ruby@v1
         with:
           ruby-version: ${{ matrix.ruby }}
+          rubygems: latest
           bundler-cache: true
 
       - name: RSpec & publish code coverage
@@ -46,3 +52,4 @@ jobs:
           CC_TEST_REPORTER_ID: b7ba588af2a540fa96c267b3655a2afe31ea29976dc25905a668dd28d5e88915
         with:
           coverageCommand: bin/rake
+        continue-on-error: ${{ matrix.allow-fail }}
diff --git a/Gemfile b/Gemfile
index f9458e44..8cc5cb31 100644
--- a/Gemfile
+++ b/Gemfile
@@ -2,12 +2,10 @@ source "https://rubygems.org"
 
 gemspec
 
+gem 'puma'
+
 platforms :ruby do
-  if RUBY_VERSION >= "2.5.0"
-    gem 'sqlite3', '~> 1.4'
-  else
-    gem 'sqlite3', '~> 1.3.6'
-  end
+  gem 'sqlite3'
 end
 
 platforms :jruby do
@@ -15,30 +13,24 @@ platforms :jruby do
   gem "activerecord-jdbcsqlite3-adapter"
 end
 
-if RUBY_VERSION >= "2.6.0"
-  gem "turbo-rails"
-  gem "redis", "~> 4.0"
-end
+gem 'mongoid'
 
-if RUBY_VERSION >= "2.5.0"
-  gem "rails", "~> 6.0"
-  gem 'webrick'
+case rails_version = ENV['RAILS_VERSION']
+when nil
+  gem 'rails'
+when 'edge'
+  gem 'rails', github: 'rails/rails'
 else
-  gem "rails", "~> 5.0"
+  gem 'rails', "~> #{rails_version}.0"
 end
 
-if RUBY_VERSION >= "2.7.0"
-  gem "mongoid", github: "mongodb/mongoid"
-elsif RUBY_VERSION >= "2.6.0"
-  gem "mongoid", "~> 8.1"
-else
-  gem "mongoid", "~> 7.2"
-end
-
-if RUBY_VERSION >= "3.1.0"
-  gem "net-imap"
-  gem "net-pop"
-  gem "net-smtp"
+case RUBY_VERSION
+when '2.6'...'3.0'
+  gem "turbo-rails", "<= 2.0.7"
+  gem "redis", "~> 4.0"
+when '3.0'...'4'
+  gem 'turbo-rails'
+  gem 'redis'
 end
 
 if RUBY_VERSION < "2.5.0"