diff --git a/.circleci/config.yml b/.circleci/config.yml
deleted file mode 100644
index 17b27aa95..000000000
--- a/.circleci/config.yml
+++ /dev/null
@@ -1,207 +0,0 @@
-version: 2
-references:
-  repo_restore_cache: &repo_restore_cache
-    restore_cache:
-      keys:
-        - repo-{{ .Environment.CIRCLE_SHA1 }}
-  repo_save_cache: &repo_save_cache
-    save_cache:
-      key: repo-{{ .Environment.CIRCLE_SHA1 }}-{{ epoch }}
-      paths:
-        - ~/airbrake
-  bundle_install: &bundle_install
-    run:
-      name: Install Bundler dependencies
-      command: bundle install --path ~/airbrake/vendor/bundle --jobs 15
-  appraisal_install: &appraisal_install
-    run:
-      name: Install Appraisal dependencies
-      command: bundle exec appraisal install --jobs 15
-  unit: &unit
-    run:
-      name: Run unit tests
-      command: bundle exec rake spec:unit
-  rails41: &rails41
-    run:
-      name: Test Rails 4.1
-      command: bundle exec appraisal rails-4.1 rake spec:integration:rails
-  rails42: &rails42
-    run:
-      name: Test Rails 4.2
-      command: bundle exec appraisal rails-4.2 rake spec:integration:rails
-  rails50: &rails50
-    run:
-      name: Test Rails 5.0
-      command: bundle exec appraisal rails-5.0 rake spec:integration:rails
-  rails51: &rails51
-    run:
-      name: Test Rails 5.1
-      command: bundle exec appraisal rails-5.1 rake spec:integration:rails
-  rails52: &rails52
-    run:
-      name: Test Rails 5.2
-      command: bundle exec appraisal rails-5.2 rake spec:integration:rails
-  rails60: &rails60
-    run:
-      name: Test Rails 6.0
-      command: bundle exec appraisal rails-6.0 rake spec:integration:rails
-  sinatra: &sinatra
-    run:
-      name: Test Sinatra
-      command: bundle exec appraisal sinatra rake spec:integration:sinatra
-  rack: &rack
-    run:
-      name: Test Rack
-      command: bundle exec appraisal rack rake spec:integration:rack
-jobs:
-  lint:
-    docker:
-      - image: circleci/ruby:2.7
-        auth:
-          username: $DOCKERHUB_USER
-          password: $DOCKERHUB_PASSWORD
-    working_directory: ~/airbrake
-    steps:
-      - checkout
-      - <<: *repo_save_cache
-      - <<: *bundle_install
-      - run:
-          name: Run RuboCop linting
-          command: bundle exec rubocop --parallel
-      - run:
-          name: Verify all @since tag versions start with letter 'v'
-          command: |
-            ! egrep -r "# @since [0-9]" lib
-  "ruby-2.3":
-    docker:
-      - image: circleci/ruby:2.3
-        auth:
-          username: $DOCKERHUB_USER
-          password: $DOCKERHUB_PASSWORD
-    working_directory: ~/airbrake
-    steps:
-      - <<: *repo_restore_cache
-      - <<: *bundle_install
-      - <<: *appraisal_install
-      - <<: *unit
-      - <<: *rails41
-      - <<: *rails42
-      - <<: *rails50
-      - <<: *rails51
-      - <<: *rails52
-      - <<: *sinatra
-      - <<: *rack
-  "ruby-2.4":
-    docker:
-      - image: circleci/ruby:2.4
-        auth:
-          username: $DOCKERHUB_USER
-          password: $DOCKERHUB_PASSWORD
-    working_directory: ~/airbrake
-    steps:
-      - <<: *repo_restore_cache
-      - <<: *bundle_install
-      - <<: *appraisal_install
-      - <<: *unit
-      - <<: *rails42
-      - <<: *rails50
-      - <<: *rails51
-      - <<: *rails52
-      - <<: *sinatra
-      - <<: *rack
-  "ruby-2.5":
-    docker:
-      - image: circleci/ruby:2.5
-        auth:
-          username: $DOCKERHUB_USER
-          password: $DOCKERHUB_PASSWORD
-    working_directory: ~/airbrake
-    steps:
-      - <<: *repo_restore_cache
-      - <<: *bundle_install
-      - <<: *appraisal_install
-      - <<: *unit
-      - <<: *rails42
-      - <<: *rails51
-      - <<: *rails52
-      - <<: *rails60
-      - <<: *sinatra
-      - <<: *rack
-  "ruby-2.6":
-    docker:
-      - image: circleci/ruby:2.6
-        auth:
-          username: $DOCKERHUB_USER
-          password: $DOCKERHUB_PASSWORD
-    working_directory: ~/airbrake
-    steps:
-      - <<: *repo_restore_cache
-      - <<: *bundle_install
-      - <<: *appraisal_install
-      - <<: *unit
-      - <<: *rails42
-      - <<: *rails50
-      - <<: *rails51
-      - <<: *rails52
-      - <<: *rails60
-      - <<: *sinatra
-      - <<: *rack
-  "ruby-2.7":
-    docker:
-      - image: circleci/ruby:2.7
-        auth:
-          username: $DOCKERHUB_USER
-          password: $DOCKERHUB_PASSWORD
-    working_directory: ~/airbrake
-    steps:
-      - <<: *repo_restore_cache
-      - <<: *bundle_install
-      - <<: *appraisal_install
-      - <<: *unit
-      - <<: *rails50
-      - <<: *rails51
-      - <<: *rails52
-      - <<: *rails60
-      - <<: *sinatra
-      - <<: *rack
-  "jruby-9.2":
-    docker:
-      - image: circleci/jruby:9.2
-        auth:
-          username: $DOCKERHUB_USER
-          password: $DOCKERHUB_PASSWORD
-    working_directory: ~/airbrake
-    steps:
-      - <<: *repo_restore_cache
-      - <<: *bundle_install
-      - <<: *appraisal_install
-      - <<: *unit
-      - <<: *rails51
-      - <<: *rails52
-      - <<: *rails60
-      - <<: *sinatra
-      - <<: *rack
-
-workflows:
-  version: 2
-  build:
-    jobs:
-      - lint
-      - "ruby-2.3":
-          requires:
-            - lint
-      - "ruby-2.4":
-          requires:
-            - lint
-      - "ruby-2.5":
-          requires:
-            - lint
-      - "ruby-2.6":
-          requires:
-            - lint
-      - "ruby-2.7":
-          requires:
-            - lint
-      - "jruby-9.2":
-          requires:
-            - lint
diff --git a/.github/dependabot.yml b/.github/dependabot.yml
index 525316af7..ec31adcaf 100644
--- a/.github/dependabot.yml
+++ b/.github/dependabot.yml
@@ -10,3 +10,9 @@ updates:
   - dependency-name: ethon
     versions:
     - 0.13.0
+- package-ecosystem: "github-actions"
+  directory: "/"
+  schedule:
+    interval: daily
+    time: "19:00"
+    timezone: US/Central
diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
new file mode 100644
index 000000000..fe0766058
--- /dev/null
+++ b/.github/workflows/test.yml
@@ -0,0 +1,64 @@
+name: airbrake
+
+on: [push]
+
+permissions:
+  contents: read
+
+jobs:
+  test:
+    strategy:
+      matrix:
+        os: [ubuntu-latest]
+        ruby: [2.6, 2.7, 3.0, 3.1, jruby]
+
+    runs-on: ${{ matrix.os }}
+
+    steps:
+      - uses: actions/checkout@v3
+
+      - name: Update package list
+        run: sudo apt-get update
+
+      - name: Install cURL Headers
+        run: sudo apt-get install libcurl4 libcurl4-openssl-dev
+
+      - uses: ruby/setup-ruby@v1
+        with:
+          ruby-version: ${{ matrix.ruby }}
+          bundler-cache: true
+
+      - name: Rubocop lint
+        run: bundle exec rubocop
+
+      - name: Install Bundler dependencies
+        run: bundle install
+
+      - name: Install Appraisal dependencies
+        run: bundle exec appraisal install
+
+      - name: Display Ruby version
+        run: ruby -v
+
+      - name: Unit tests
+        run: bundle exec rake spec:unit
+
+      - name: Test Rails 5.2
+        if: ${{ matrix.ruby != '3.0' && matrix.ruby != '3.1' }}
+        run: bundle exec appraisal rails-5.2 rake spec:integration:rails
+
+      - name: Test Rails 6.0
+        run: bundle exec appraisal rails-6.0 rake spec:integration:rails
+
+      - name: Test Rails 6.1
+        run: bundle exec appraisal rails-6.1 rake spec:integration:rails
+
+      - name: Test Rails 7.0
+        if: ${{ matrix.ruby != '2.6' && matrix.ruby != 'jruby' }}
+        run: bundle exec appraisal rails-7.0 rake spec:integration:rails
+
+      - name: Test Sinatra
+        run: bundle exec appraisal sinatra rake spec:integration:sinatra
+
+      - name: Test Rack
+        run: bundle exec appraisal rack rake spec:integration:rack
diff --git a/.rubocop.yml b/.rubocop.yml
index 560391fc3..94f7bd474 100644
--- a/.rubocop.yml
+++ b/.rubocop.yml
@@ -1,9 +1,13 @@
 # Explanations of all possible options:
 #   https://github.com/bbatsov/rubocop/blob/master/config/default.yml
 AllCops:
-  TargetRubyVersion: 2.3
+  TargetRubyVersion: 2.6
   DisplayCopNames: true
   DisplayStyleGuide: true
+  NewCops: enable
+  Exclude:
+    - 'gemfiles/*.gemfile'
+    - 'vendor/**/*'
 
 Metrics/MethodLength:
   Max: 25
@@ -41,6 +45,9 @@ Style/FrozenStringLiteralComment:
 Metrics/BlockLength:
   CountComments: false
   Max: 25
+  IgnoredMethods:
+    - describe
+    - context
   Exclude:
     - 'Rakefile'
     - '**/*.rake'
diff --git a/Appraisals b/Appraisals
index 8d41fc41b..3ffd88298 100644
--- a/Appraisals
+++ b/Appraisals
@@ -1,106 +1,75 @@
 # frozen_string_literal: true
 
-if Gem::Version.new(RUBY_VERSION) < Gem::Version.new('2.7.0') && RUBY_ENGINE != 'jruby'
-  appraise 'rails-4.1' do
-    gem 'rails', '~> 4.1.16'
-    gem 'warden', '~> 1.2.3'
-
-    gem 'activerecord-jdbcsqlite3-adapter', '~> 1.3.18', platforms: :jruby
-    gem 'sqlite3', '~> 1.3.11', platforms: %i[mri rbx]
-
-    gem 'resque', '~> 1.25.2'
-    gem 'resque_spec', github: 'airbrake/resque_spec'
-
-    gem 'delayed_job_active_record', '~> 4.1.0'
-
-    gem 'mime-types', '~> 3.1'
-    gem 'sprockets', '~> 3.7'
-    gem 'rack', '~> 1'
-  end
-
-  appraise 'rails-4.2' do
-    gem 'rails', '~> 4.2.10'
-    gem 'warden', '~> 1.2.3'
+# Rails 5 doesn't work on Ruby 3+.
+if Gem::Version.new(RUBY_VERSION) < Gem::Version.new('3.0.0')
+  appraise 'rails-5.2' do
+    gem 'rails', '~> 5.2.0'
+    gem 'warden', '~> 1.2.6'
+    gem 'rack', '~> 2.0'
 
-    gem 'activerecord-jdbcsqlite3-adapter', '~> 1.3.18', platforms: :jruby
-    gem 'sqlite3', '~> 1.3.11', platforms: %i[mri rbx]
+    gem 'activerecord-jdbcsqlite3-adapter', '~> 52.0', platforms: :jruby
+    gem 'sqlite3', '~> 1.4', platforms: %i[mri rbx]
 
-    gem 'resque', '~> 1.25.2'
+    gem 'resque', '~> 1.26'
     gem 'resque_spec', github: 'airbrake/resque_spec'
 
-    gem 'delayed_job_active_record', '~> 4.1.0'
+    gem 'delayed', '~> 0.4'
 
     gem 'mime-types', '~> 3.1'
-    gem 'sprockets', '~> 3.7'
-    gem 'rack', '~> 1'
   end
 end
 
-appraise 'rails-5.0' do
-  gem 'rails', '~> 5.0.7'
-  gem 'warden', '~> 1.2.3'
-
-  gem 'activerecord-jdbcsqlite3-adapter', '~> 1.3.18', platforms: :jruby
-  gem 'sqlite3', '~> 1.3.11', platforms: %i[mri rbx]
-
-  gem 'resque', '~> 1.25.2'
-  gem 'resque_spec', github: 'airbrake/resque_spec'
-
-  gem 'delayed_job_active_record', '~> 4.1.0'
-
-  gem 'mime-types', '~> 3.1'
-  gem 'sprockets', '~> 3.7'
-end
-
-appraise 'rails-5.1' do
-  gem 'rails', '~> 5.1.4'
+appraise 'rails-6.0' do
+  gem 'rails', '~> 6.0.4.1'
   gem 'warden', '~> 1.2.6'
+  gem 'rack', '~> 2.0'
 
-  gem 'activerecord-jdbcsqlite3-adapter', '~> 51.0', platforms: :jruby
-  gem 'sqlite3', '~> 1.3.11', platforms: %i[mri rbx]
+  gem 'activerecord-jdbcsqlite3-adapter', '~> 60.1', platforms: :jruby
+  gem 'sqlite3', '~> 1.4', platforms: %i[mri rbx]
 
   gem 'resque', '~> 1.26'
   gem 'resque_spec', github: 'airbrake/resque_spec'
 
-  gem 'delayed_job', github: 'collectiveidea/delayed_job'
-  gem 'delayed_job_active_record', '~> 4.1'
+  gem 'delayed', '~> 0.4'
 
   gem 'mime-types', '~> 3.1'
-  gem 'sprockets', '~> 3.7'
 end
 
-appraise 'rails-5.2' do
-  gem 'rails', '~> 5.2.0'
+appraise 'rails-6.1' do
+  gem 'rails', '~> 6.1.4.1'
   gem 'warden', '~> 1.2.6'
   gem 'rack', '~> 2.0'
 
-  gem 'activerecord-jdbcsqlite3-adapter', '~> 52.0', platforms: :jruby
-  gem 'sqlite3', '~> 1.3.11', platforms: %i[mri rbx]
+  gem 'activerecord-jdbcsqlite3-adapter',
+      github: 'jruby/activerecord-jdbc-adapter',
+      branch: '61-stable',
+      platforms: :jruby
+  gem 'sqlite3', '~> 1.4', platforms: %i[mri rbx]
 
   gem 'resque', '~> 1.26'
   gem 'resque_spec', github: 'airbrake/resque_spec'
 
-  gem 'delayed_job', github: 'collectiveidea/delayed_job'
-  gem 'delayed_job_active_record', '~> 4.1'
+  gem 'delayed', '~> 0.4'
 
   gem 'mime-types', '~> 3.1'
 end
 
-# Rails 6.0+ supports only modern Rubies (2.5+)
-if Gem::Version.new(RUBY_VERSION) >= Gem::Version.new('2.5')
-  appraise 'rails-6.0' do
-    gem 'rails', '~> 6.0.2'
+if Gem::Version.new(RUBY_VERSION) >= Gem::Version.new('2.7.0')
+  appraise 'rails-7.0' do
+    gem 'rails', '~> 7.0.1'
     gem 'warden', '~> 1.2.6'
     gem 'rack', '~> 2.0'
 
-    gem 'activerecord-jdbcsqlite3-adapter', '~> 60.1', platforms: :jruby
+    gem 'activerecord-jdbcsqlite3-adapter',
+        github: 'jruby/activerecord-jdbc-adapter',
+        branch: '61-stable',
+        platforms: :jruby
     gem 'sqlite3', '~> 1.4', platforms: %i[mri rbx]
 
     gem 'resque', '~> 1.26'
     gem 'resque_spec', github: 'airbrake/resque_spec'
 
-    gem 'delayed_job', github: 'collectiveidea/delayed_job'
-    gem 'delayed_job_active_record', '~> 4.1'
+    gem 'delayed', '~> 0.4'
 
     gem 'mime-types', '~> 3.1'
   end
diff --git a/CHANGELOG.md b/CHANGELOG.md
index a4f504c70..837e541e2 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -3,6 +3,70 @@ Airbrake Changelog
 
 ### master
 
+### [v13.0.2][v13.0.2] (May 20, 2022)
+
+* Fixed support of APM on Rails 7+, where the reported time of a performance
+  breakdowns and queries malformed, resulting in the complete rejection of the
+  performance breakdowns or queries by the backend. This improves on the fix
+  introduced in v13.0.1
+  ([#1227](https://github.com/airbrake/airbrake/issues/1227))
+
+### [v13.0.1][v13.0.1] (May 13, 2022)
+
+* Fixed support of APM on Rails 7+, where the reported time of a route was
+  malformed, resulting in the complete rejection of the route stats by the
+  backend ([#1223](https://github.com/airbrake/airbrake/issues/1223))
+* Fixed bug where Rails 6+ apps that don't require ActiveRecord crash when
+  Airbrake is installed
+  ([#1224](https://github.com/airbrake/airbrake/pull/1224))
+
+### [v13.0.0][v13.0.0] (January 18, 2022)
+
+Breaking changes:
+
+* Dropped support for Ruby 2.5
+  ([#1208](https://github.com/airbrake/airbrake/issues/1208))
+
+Bug fixes:
+
+* Fixed APM not working on Rails 7 due to ``NoMethodError (undefined method
+  `glob?' for nil:NilClass)``
+  ([#1211](https://github.com/airbrake/airbrake/issues/1211))
+
+### [v12.0.0][v12.0.0] (September 22, 2021)
+
+Breaking changes:
+
+* Dropped support for Ruby 2.3
+  ([#1180](https://github.com/airbrake/airbrake/issues/1180))
+* Dropped support for Ruby 2.4
+  ([#1180](https://github.com/airbrake/airbrake/issues/1180))
+
+Maintenance:
+
+* Bumped `airbrake-ruby` requirement to `~> 6.0`
+  ([#1179](https://github.com/airbrake/airbrake/pull/1179))
+
+Other changes:
+
+* Rails generator no longer embeds project id & project key into the generated
+  initializer file. Set environment variables instead.
+
+  Before:
+
+  ```sh
+  % rails g airbrake PROJECT_ID PROJECT_KEY
+  ```
+
+  After:
+
+  ```sh
+  export AIRBRAKE_PROJECT_ID=<PROJECT ID>
+  export AIRBRAKE_PROJECT_KEY=<PROJECT KEY>
+
+  rails g airbrake
+  ```
+
 ### [v11.0.3][v11.0.3] (May 13, 2021)
 
 * Fixed `Sneakers` integration when 3rd party code monkey-patches
@@ -258,12 +322,12 @@ Features:
 
 ### [v9.2.2][v9.2.2] (May 10, 2019)
 
-* Rails: started attaching Rack request and User info to the resource object,
+* Rails: started attaching Rack request and User info to the metric object,
   which is accessible through performance hooks:
 
   ```ruby
-  Airbrake.add_performance_filter do |resource|
-    if resource.stash.key?(:user)
+  Airbrake.add_performance_filter do |metric|
+    if metric.stash.key?(:user)
       # custom logic
     end
   end
@@ -948,3 +1012,7 @@ Features:
 [v11.0.1]: https://github.com/airbrake/airbrake/releases/tag/v11.0.1
 [v11.0.2]: https://github.com/airbrake/airbrake/releases/tag/v11.0.2
 [v11.0.3]: https://github.com/airbrake/airbrake/releases/tag/v11.0.3
+[v12.0.0]: https://github.com/airbrake/airbrake/releases/tag/v12.0.0
+[v13.0.0]: https://github.com/airbrake/airbrake/releases/tag/v13.0.0
+[v13.0.1]: https://github.com/airbrake/airbrake/releases/tag/v13.0.1
+[v13.0.2]: https://github.com/airbrake/airbrake/releases/tag/v13.0.2
diff --git a/Gemfile b/Gemfile
index f34491897..144688c3b 100644
--- a/Gemfile
+++ b/Gemfile
@@ -1,4 +1,5 @@
 source 'https://rubygems.org'
 gemspec
 
-gem 'rubocop', '= 0.81', require: false
+gem 'rubocop', '~> 1.21', require: false
+gem 'sneakers', github: 'jondot/sneakers', ref: '31d0cb25dc5bbcfb0749567e9e0f80e6353fb66b'
diff --git a/LICENSE.md b/LICENSE.md
index 114f60f9c..3522d9ba9 100644
--- a/LICENSE.md
+++ b/LICENSE.md
@@ -1,7 +1,7 @@
 The MIT License
 ===============
 
-Copyright © 2021 Airbrake Technologies, Inc.
+Copyright © 2022 Airbrake Technologies, Inc.
 
 Permission is hereby granted, free of charge, to any person obtaining a copy of
 this software and associated documentation files (the 'Software'), to deal in
diff --git a/README.md b/README.md
index 4b56b0731..3cbd213f1 100644
--- a/README.md
+++ b/README.md
@@ -1,7 +1,7 @@
 Airbrake
 ========
 
-[![Circle Build Status](https://circleci.com/gh/airbrake/airbrake.png?style=shield)](https://circleci.com/gh/airbrake/airbrake)
+[![Build Status](https://github.com/airbrake/airbrake/workflows/airbrake/badge.svg)](https://github.com/airbrake/airbrake/actions)
 [![Code Climate](https://codeclimate.com/github/airbrake/airbrake.svg)](https://codeclimate.com/github/airbrake/airbrake)
 [![Gem Version](https://badge.fury.io/rb/airbrake.svg)](http://badge.fury.io/rb/airbrake)
 [![Documentation Status](http://inch-ci.org/github/airbrake/airbrake.svg?branch=master)](http://inch-ci.org/github/airbrake/airbrake)
@@ -47,26 +47,26 @@ The list of integrations that are available in this gem includes:
 
 * [Heroku support][heroku-docs] (as an [add-on][heroku-addon])
 * Web frameworks
-  * Rails<sup>[[link](#rails)]</sup>
-  * Sinatra<sup>[[link](#sinatra)]</sup>
-  * Rack applications<sup>[[link](#rack)]</sup>
+  * [Rails](#rails)
+  * [Sinatra](#sinatra)
+  * [Rack applications](#rack)
 * Job processing libraries
-  * ActiveJob<sup>[[link](#activejob)]</sup>
-  * Resque<sup>[[link](#resque)]</sup>
-  * Sidekiq<sup>[[link](#sidekiq)]</sup>
-  * DelayedJob<sup>[[link](#delayedjob)]</sup>
-  * Shoryuken<sup>[[link](#shoryuken)]</sup>
-  * Sneakers<sup>[[link](#sneakers)]</sup>
+  * [ActiveJob](#activejob)
+  * [Resque](#resque)
+  * [Sidekiq](#sidekiq)
+  * [DelayedJob](#delayedjob)
+  * [Shoryuken](#shoryuken)
+  * [Sneakers](#sneakers)
 * Other libraries
-  * ActionCable<sup>[[link](#actioncable)]</sup>
-  * Rake<sup>[[link](#rake)]</sup>
-  * Logger<sup>[[link](#logger)]</sup>
-* Plain Ruby scripts<sup>[[link](#plain-ruby-scripts)]</sup>
+  * [ActionCable](#actioncable)
+  * [Rake](#rake)
+  * [Logger](#logger)
+* [Plain Ruby scripts](#plain-ruby-scripts)
 
 Deployment tracking:
 
-* Using Capistrano<sup>[[link](#capistrano)]</sup>
-* Using the Rake task<sup>[[link](#rake-task)]</sup>
+* Using [Capistrano](#capistrano)
+* Using the [Rake task](#rake-task)
 
 Installation
 ------------
@@ -94,17 +94,21 @@ Configuration
 
 #### Integration
 
-To integrate Airbrake with your Rails application, you need to know
-your [project id and project key][project-idkey]. Invoke the following command
-and replace `PROJECT_ID` and `PROJECT_KEY` with your values:
+To integrate Airbrake with your Rails application, you need to know your
+[project id and project key][project-idkey]. Set `AIRBRAKE_PROJECT_ID` &
+`AIRBRAKE_PROJECT_KEY` environment variables with your project's values and
+generate the Airbrake config:
 
 ```bash
-rails g airbrake PROJECT_ID PROJECT_KEY
+export AIRBRAKE_PROJECT_ID=<PROJECT ID>
+export AIRBRAKE_PROJECT_KEY=<PROJECT KEY>
+
+rails g airbrake
 ```
 
-[Heroku add-on][heroku-addon] users can omit specifying the key and the id and
-invoke the command without arguments (Heroku add-on's environment variables will
-be used) ([Heroku add-on docs][heroku-docs]):
+[Heroku add-on][heroku-addon] users can omit specifying the key and the
+id. Heroku add-on's environment variables will be used ([Heroku add-on
+docs][heroku-docs]):
 
 ```bash
 rails g airbrake
@@ -488,7 +492,7 @@ wrap your logger in Airbrake's decorator class:
 require 'airbrake/logger'
 
 # Create a normal logger
-logger = Logger.new(STDOUT)
+logger = Logger.new($stdout)
 
 # Wrap it
 logger = Airbrake::AirbrakeLogger.new(logger)
@@ -647,7 +651,7 @@ Then, invoke it like shown in the example for Rails.
 Supported Rubies
 ----------------
 
-* CRuby >= 2.3.0
+* CRuby >= 2.6.0
 * JRuby >= 9k
 
 Contact
@@ -698,8 +702,8 @@ bundle exec appraisal rails-4.2 rake spec:integration:rails
 bundle exec appraisal sinatra rake spec:integration:sinatra
 ```
 
-Pro tip: [CircleCI config](/.circleci/config.yml) has the list of all
-integration tests and commands to invoke them.
+Pro tip: [GitHub Actions config](/.github/workflows/test.yml) has the list of
+all the integration tests and commands to invoke them.
 
 [airbrake.io]: https://airbrake.io
 [airbrake-ruby]: https://github.com/airbrake/airbrake-ruby
diff --git a/airbrake.gemspec b/airbrake.gemspec
index f5f7abd04..64e117d4f 100644
--- a/airbrake.gemspec
+++ b/airbrake.gemspec
@@ -3,7 +3,6 @@ require './lib/airbrake/version'
 Gem::Specification.new do |s|
   s.name        = 'airbrake'
   s.version     = Airbrake::AIRBRAKE_VERSION.dup
-  s.date        = Time.now.strftime('%Y-%m-%d')
   s.summary     = <<SUMMARY
 Airbrake is an online tool that provides robust exception tracking in any of
 your Ruby applications.
@@ -28,9 +27,13 @@ DESC
   s.require_path = 'lib'
   s.files        = ['lib/airbrake.rb', *Dir.glob('lib/**/*')]
 
-  s.required_ruby_version = '>= 2.3'
+  s.required_ruby_version = '>= 2.6'
 
-  s.add_dependency 'airbrake-ruby', '~> 5.1'
+  s.metadata = {
+    'rubygems_mfa_required' => 'true',
+  }
+
+  s.add_dependency 'airbrake-ruby', '~> 6.0'
 
   s.add_development_dependency 'rspec', '~> 3'
   s.add_development_dependency 'rspec-wait', '~> 0'
@@ -40,24 +43,18 @@ DESC
   s.add_development_dependency 'rack', '~> 2'
   s.add_development_dependency 'webmock', '~> 3'
   s.add_development_dependency 'amq-protocol'
-  s.add_development_dependency 'sneakers', '~> 2'
-  s.add_development_dependency 'rack-test', '= 0.6.3'
-  s.add_development_dependency 'redis', '= 4.1.4'
-  s.add_development_dependency 'sidekiq', '~> 5'
-  s.add_development_dependency 'curb', '~> 0.9' if RUBY_ENGINE == 'ruby'
+  s.add_development_dependency 'rack-test', '~> 1.1'
+  s.add_development_dependency 'redis', '~> 4.5'
+  s.add_development_dependency 'sidekiq', '~> 6'
+  s.add_development_dependency 'curb', '~> 1.0' if RUBY_ENGINE == 'ruby'
   s.add_development_dependency 'excon', '~> 0.64'
-  s.add_development_dependency 'http', '~> 2.2'
+  s.add_development_dependency 'http', '~> 5.0'
   s.add_development_dependency 'httpclient', '~> 2.8'
   s.add_development_dependency 'typhoeus', '~> 1.3'
 
-  # Fixes build failure with ethon v0.13.0
-  # https://app.circleci.com/pipelines/github/airbrake/airbrake/158/workflows/f22d902f-f0bb-449b-8b95-2a0ac76047f2
-  s.add_development_dependency 'ethon', '= 0.12.0'
-
   # Fixes build failure with public_suffix v3
   # https://circleci.com/gh/airbrake/airbrake-ruby/889
   s.add_development_dependency 'public_suffix', '~> 4.0', '< 5.0'
 
-  # redis-namespace > 1.6.0 wants Ruby >= 2.4.
-  s.add_development_dependency 'redis-namespace', '= 1.6.0'
+  s.add_development_dependency 'redis-namespace', '~> 1.8'
 end
diff --git a/gemfiles/rack.gemfile b/gemfiles/rack.gemfile
index b30d6525d..fb5db120a 100644
--- a/gemfiles/rack.gemfile
+++ b/gemfiles/rack.gemfile
@@ -2,7 +2,8 @@
 
 source "https://rubygems.org"
 
-gem "rubocop", "= 0.55", require: false
+gem "rubocop", "~> 1.21", require: false
+gem "sneakers", github: "jondot/sneakers", ref: "31d0cb25dc5bbcfb0749567e9e0f80e6353fb66b"
 gem "warden", "~> 1.2.6"
 
 gemspec path: "../"
diff --git a/gemfiles/rails_4.0.gemfile b/gemfiles/rails_4.0.gemfile
deleted file mode 100644
index b2b99eeed..000000000
--- a/gemfiles/rails_4.0.gemfile
+++ /dev/null
@@ -1,15 +0,0 @@
-# This file was generated by Appraisal
-
-source "https://rubygems.org"
-
-gem "rubocop", "= 0.51", require: false
-gem "rails", "~> 4.0.13"
-gem "warden", "~> 1.2.3"
-gem "activerecord-jdbcsqlite3-adapter", "~> 1.3.18", platforms: :jruby
-gem "sqlite3", "~> 1.3.11", platforms: [:mri, :rbx]
-gem "resque", "~> 1.25.2"
-gem "resque_spec", github: "airbrake/resque_spec"
-gem "delayed_job_active_record", "~> 4.1.0"
-gem "mime-types", "~> 3.1"
-
-gemspec path: "../"
diff --git a/gemfiles/rails_4.1.gemfile b/gemfiles/rails_4.1.gemfile
deleted file mode 100644
index 0cab4cbaa..000000000
--- a/gemfiles/rails_4.1.gemfile
+++ /dev/null
@@ -1,17 +0,0 @@
-# This file was generated by Appraisal
-
-source "https://rubygems.org"
-
-gem "rubocop", "= 0.55", require: false
-gem "rails", "~> 4.1.16"
-gem "warden", "~> 1.2.3"
-gem "activerecord-jdbcsqlite3-adapter", "~> 1.3.18", platforms: :jruby
-gem "sqlite3", "~> 1.3.11", platforms: [:mri, :rbx]
-gem "resque", "~> 1.25.2"
-gem "resque_spec", github: "airbrake/resque_spec"
-gem "delayed_job_active_record", "~> 4.1.0"
-gem "mime-types", "~> 3.1"
-gem "sprockets", "~> 3.7"
-gem "rack", "~> 1"
-
-gemspec path: "../"
diff --git a/gemfiles/rails_4.2.gemfile b/gemfiles/rails_4.2.gemfile
deleted file mode 100644
index 5776db595..000000000
--- a/gemfiles/rails_4.2.gemfile
+++ /dev/null
@@ -1,17 +0,0 @@
-# This file was generated by Appraisal
-
-source "https://rubygems.org"
-
-gem "rubocop", "= 0.55", require: false
-gem "rails", "~> 4.2.10"
-gem "warden", "~> 1.2.3"
-gem "activerecord-jdbcsqlite3-adapter", "~> 1.3.18", platforms: :jruby
-gem "sqlite3", "~> 1.3.11", platforms: [:mri, :rbx]
-gem "resque", "~> 1.25.2"
-gem "resque_spec", github: "airbrake/resque_spec"
-gem "delayed_job_active_record", "~> 4.1.0"
-gem "mime-types", "~> 3.1"
-gem "sprockets", "~> 3.7"
-gem "rack", "~> 1"
-
-gemspec path: "../"
diff --git a/gemfiles/rails_5.0.gemfile b/gemfiles/rails_5.0.gemfile
deleted file mode 100644
index 1869db61f..000000000
--- a/gemfiles/rails_5.0.gemfile
+++ /dev/null
@@ -1,16 +0,0 @@
-# This file was generated by Appraisal
-
-source "https://rubygems.org"
-
-gem "rubocop", "= 0.55", require: false
-gem "rails", "~> 5.0.7"
-gem "warden", "~> 1.2.3"
-gem "activerecord-jdbcsqlite3-adapter", "~> 1.3.18", platforms: :jruby
-gem "sqlite3", "~> 1.3.11", platforms: [:mri, :rbx]
-gem "resque", "~> 1.25.2"
-gem "resque_spec", github: "airbrake/resque_spec"
-gem "delayed_job_active_record", "~> 4.1.0"
-gem "mime-types", "~> 3.1"
-gem "sprockets", "~> 3.7"
-
-gemspec path: "../"
diff --git a/gemfiles/rails_5.1.gemfile b/gemfiles/rails_5.1.gemfile
deleted file mode 100644
index 3dd5ffd32..000000000
--- a/gemfiles/rails_5.1.gemfile
+++ /dev/null
@@ -1,17 +0,0 @@
-# This file was generated by Appraisal
-
-source "https://rubygems.org"
-
-gem "rubocop", "= 0.55", require: false
-gem "rails", "~> 5.1.4"
-gem "warden", "~> 1.2.6"
-gem "activerecord-jdbcsqlite3-adapter", "~> 51.0", platforms: :jruby
-gem "sqlite3", "~> 1.3.11", platforms: [:mri, :rbx]
-gem "resque", "~> 1.26"
-gem "resque_spec", github: "airbrake/resque_spec"
-gem "delayed_job", github: "collectiveidea/delayed_job"
-gem "delayed_job_active_record", "~> 4.1"
-gem "mime-types", "~> 3.1"
-gem "sprockets", "~> 3.7"
-
-gemspec path: "../"
diff --git a/gemfiles/rails_5.2.gemfile b/gemfiles/rails_5.2.gemfile
index 1da3cd83f..efc496180 100644
--- a/gemfiles/rails_5.2.gemfile
+++ b/gemfiles/rails_5.2.gemfile
@@ -2,12 +2,13 @@
 
 source "https://rubygems.org"
 
-gem "rubocop", "= 0.55", require: false
+gem "rubocop", "~> 1.21", require: false
+gem "sneakers", github: "jondot/sneakers", ref: "31d0cb25dc5bbcfb0749567e9e0f80e6353fb66b"
 gem "rails", "~> 5.2.0"
 gem "warden", "~> 1.2.6"
 gem "rack", "~> 2.0"
 gem "activerecord-jdbcsqlite3-adapter", "~> 52.0", platforms: :jruby
-gem "sqlite3", "~> 1.3.11", platforms: [:mri, :rbx]
+gem "sqlite3", "~> 1.4", platforms: [:mri, :rbx]
 gem "resque", "~> 1.26"
 gem "resque_spec", github: "airbrake/resque_spec"
 gem "delayed_job", github: "collectiveidea/delayed_job"
diff --git a/gemfiles/rails_6.0.gemfile b/gemfiles/rails_6.0.gemfile
index 7e241d218..1d23b2155 100644
--- a/gemfiles/rails_6.0.gemfile
+++ b/gemfiles/rails_6.0.gemfile
@@ -2,16 +2,16 @@
 
 source "https://rubygems.org"
 
-gem "rubocop", "= 0.55", require: false
-gem "rails", "~> 6.0.2"
+gem "rubocop", "~> 1.21", require: false
+gem "sneakers", github: "jondot/sneakers", ref: "31d0cb25dc5bbcfb0749567e9e0f80e6353fb66b"
+gem "rails", "~> 6.0.4.1"
 gem "warden", "~> 1.2.6"
 gem "rack", "~> 2.0"
 gem "activerecord-jdbcsqlite3-adapter", "~> 60.1", platforms: :jruby
 gem "sqlite3", "~> 1.4", platforms: [:mri, :rbx]
 gem "resque", "~> 1.26"
 gem "resque_spec", github: "airbrake/resque_spec"
-gem "delayed_job", github: "collectiveidea/delayed_job"
-gem "delayed_job_active_record", "~> 4.1"
+gem "delayed", "~> 0.4"
 gem "mime-types", "~> 3.1"
 
 gemspec path: "../"
diff --git a/gemfiles/rails_6.1.gemfile b/gemfiles/rails_6.1.gemfile
new file mode 100644
index 000000000..a035e1e42
--- /dev/null
+++ b/gemfiles/rails_6.1.gemfile
@@ -0,0 +1,17 @@
+# This file was generated by Appraisal
+
+source "https://rubygems.org"
+
+gem "rubocop", "~> 1.21", require: false
+gem "sneakers", github: "jondot/sneakers", ref: "31d0cb25dc5bbcfb0749567e9e0f80e6353fb66b"
+gem "rails", "~> 6.1.4.1"
+gem "warden", "~> 1.2.6"
+gem "rack", "~> 2.0"
+gem "activerecord-jdbcsqlite3-adapter", github: "jruby/activerecord-jdbc-adapter", branch: "61-stable", platforms: :jruby
+gem "sqlite3", "~> 1.4", platforms: [:mri, :rbx]
+gem "resque", "~> 1.26"
+gem "resque_spec", github: "airbrake/resque_spec"
+gem "delayed", "~> 0.4"
+gem "mime-types", "~> 3.1"
+
+gemspec path: "../"
diff --git a/gemfiles/rails_7.0.gemfile b/gemfiles/rails_7.0.gemfile
new file mode 100644
index 000000000..82e44a3fc
--- /dev/null
+++ b/gemfiles/rails_7.0.gemfile
@@ -0,0 +1,17 @@
+# This file was generated by Appraisal
+
+source "https://rubygems.org"
+
+gem "rubocop", "~> 1.21", require: false
+gem "sneakers", github: "jondot/sneakers", ref: "31d0cb25dc5bbcfb0749567e9e0f80e6353fb66b"
+gem "rails", "~> 7.0.1"
+gem "warden", "~> 1.2.6"
+gem "rack", "~> 2.0"
+gem "activerecord-jdbcsqlite3-adapter", github: "jruby/activerecord-jdbc-adapter", branch: "61-stable", platforms: :jruby
+gem "sqlite3", "~> 1.4", platforms: [:mri, :rbx]
+gem "resque", "~> 1.26"
+gem "resque_spec", github: "airbrake/resque_spec"
+gem "delayed", "~> 0.4"
+gem "mime-types", "~> 3.1"
+
+gemspec path: "../"
diff --git a/gemfiles/sinatra.gemfile b/gemfiles/sinatra.gemfile
index a87e20a15..df8d0686b 100644
--- a/gemfiles/sinatra.gemfile
+++ b/gemfiles/sinatra.gemfile
@@ -2,7 +2,8 @@
 
 source "https://rubygems.org"
 
-gem "rubocop", "= 0.55", require: false
+gem "rubocop", "~> 1.21", require: false
+gem "sneakers", github: "jondot/sneakers", ref: "31d0cb25dc5bbcfb0749567e9e0f80e6353fb66b"
 gem "sinatra", "~> 2"
 gem "warden", "~> 1.2.6"
 
diff --git a/lib/airbrake/capistrano/capistrano2.rb b/lib/airbrake/capistrano/capistrano2.rb
index 01cca28eb..d242eaafa 100644
--- a/lib/airbrake/capistrano/capistrano2.rb
+++ b/lib/airbrake/capistrano/capistrano2.rb
@@ -21,7 +21,7 @@ def self.load_into(config)
                 RAILS_ENV=#{fetch(:rails_env, nil)} \
 
                 bundle exec rake airbrake:deploy \
-                  USERNAME=#{Shellwords.shellescape(ENV['USER'] || ENV['USERNAME'])} \
+                  USERNAME=#{Shellwords.shellescape(ENV.fetch('USER', nil) || ENV.fetch('USERNAME', nil))} \
                   ENVIRONMENT=#{fetch(:airbrake_env, fetch(:rails_env, 'production'))} \
                   REVISION=#{current_revision.strip} \
                   REPOSITORY=#{repository} \
diff --git a/lib/airbrake/delayed_job.rb b/lib/airbrake/delayed_job.rb
index 31fa47cbc..76d07afe8 100644
--- a/lib/airbrake/delayed_job.rb
+++ b/lib/airbrake/delayed_job.rb
@@ -7,41 +7,39 @@ module Plugins
     class Airbrake < ::Delayed::Plugin
       callbacks do |lifecycle|
         lifecycle.around(:invoke_job) do |job, *args, &block|
-          begin
-            timing = ::Airbrake::Benchmark.measure do
-              # Forward the call to the next callback in the callback chain
-              block.call(job, *args)
-            end
-          rescue Exception => exception # rubocop:disable Lint/RescueException
-            params = job.as_json
+          timing = ::Airbrake::Benchmark.measure do
+            # Forward the call to the next callback in the callback chain
+            block.call(job, *args)
+          end
+        rescue Exception => exception # rubocop:disable Lint/RescueException
+          params = job.as_json
 
-            # If DelayedJob is used through ActiveJob, it contains extra info.
-            if job.payload_object.respond_to?(:job_data)
-              params[:active_job] = job.payload_object.job_data
-              job_class = job.payload_object.job_data['job_class']
-            end
+          # If DelayedJob is used through ActiveJob, it contains extra info.
+          if job.payload_object.respond_to?(:job_data)
+            params[:active_job] = job.payload_object.job_data
+            job_class = job.payload_object.job_data['job_class']
+          end
 
-            action = job_class || job.payload_object.class.name
+          action = job_class || job.payload_object.class.name
 
-            ::Airbrake.notify(exception, params) do |notice|
-              notice[:context][:component] = 'delayed_job'
-              notice[:context][:action] = action
-            end
+          ::Airbrake.notify(exception, params) do |notice|
+            notice[:context][:component] = 'delayed_job'
+            notice[:context][:action] = action
+          end
 
-            ::Airbrake.notify_queue(
-              queue: action,
-              error_count: 1,
-              timing: 0.01,
-            )
+          ::Airbrake.notify_queue(
+            queue: action,
+            error_count: 1,
+            timing: 0.01,
+          )
 
-            raise exception
-          else
-            ::Airbrake.notify_queue(
-              queue: job_class || job.payload_object.class.name,
-              error_count: 0,
-              timing: timing,
-            )
-          end
+          raise exception
+        else
+          ::Airbrake.notify_queue(
+            queue: job_class || job.payload_object.class.name,
+            error_count: 0,
+            timing: timing,
+          )
         end
       end
     end
diff --git a/lib/airbrake/logger.rb b/lib/airbrake/logger.rb
index 66157960e..73f4c6066 100644
--- a/lib/airbrake/logger.rb
+++ b/lib/airbrake/logger.rb
@@ -9,7 +9,7 @@ module Airbrake
   #
   # @example
   #   # Create a logger like you normally do and decorate it.
-  #   logger = Airbrake::AirbrakeLogger.new(Logger.new(STDOUT))
+  #   logger = Airbrake::AirbrakeLogger.new(Logger.new($stdout))
   #
   #   # Just use the logger like you normally do.
   #   logger.fatal('oops')
@@ -24,6 +24,8 @@ class AirbrakeLogger < SimpleDelegator
     attr_reader :airbrake_level
 
     def initialize(logger)
+      super
+
       __setobj__(logger)
       @airbrake_notifier = Airbrake
       self.level = logger.level
diff --git a/lib/airbrake/rack/context_filter.rb b/lib/airbrake/rack/context_filter.rb
index 3d44a9041..bc60dd812 100644
--- a/lib/airbrake/rack/context_filter.rb
+++ b/lib/airbrake/rack/context_filter.rb
@@ -20,14 +20,9 @@ def call(notice)
         context = notice[:context]
 
         context[:url] = request.url
-        context[:userAddr] =
-          if request.respond_to?(:remote_ip)
-            request.remote_ip
-          else
-            request.ip
-          end
         context[:userAgent] = request.user_agent
 
+        add_ip(context, request)
         add_framework_version(context)
 
         controller = request.env['action_controller.instance']
@@ -60,6 +55,15 @@ def framework_version
             }
           end
       end
+
+      def add_ip(context, request)
+        context[:userAddr] =
+          if request.respond_to?(:remote_ip)
+            request.remote_ip
+          else
+            request.ip
+          end
+      end
     end
   end
 end
diff --git a/lib/airbrake/rack/instrumentable.rb b/lib/airbrake/rack/instrumentable.rb
index f46581613..725b41381 100644
--- a/lib/airbrake/rack/instrumentable.rb
+++ b/lib/airbrake/rack/instrumentable.rb
@@ -57,6 +57,7 @@ def self.prepend_capture_timing(klass, method_name, label)
         klass.module_exec do
           mod = __airbrake_capture_timing_module__
           mod.module_exec do
+            # rubocop:disable Style/DocumentDynamicEvalDefinition
             module_eval <<-RUBY, __FILE__, __LINE__ + 1
               def #{method_name}(#{args})
                 Airbrake::Rack.capture_timing(#{label.to_s.inspect}) do
@@ -65,6 +66,7 @@ def #{method_name}(#{args})
               end
               #{visibility} :#{method_name}
             RUBY
+            # rubocop:enable Style/DocumentDynamicEvalDefinition
           end
           prepend mod
         end
@@ -83,6 +85,7 @@ def self.chain_capture_timing(klass, method_name, label)
         klass.module_exec do
           alias_method wrapped_method_name, method_name
           remove_method method_name if needs_removal
+          # rubocop:disable Style/DocumentDynamicEvalDefinition
           module_eval <<-RUBY, __FILE__, __LINE__ + 1
             def #{method_name}(#{args})
               Airbrake::Rack.capture_timing(#{label.to_s.inspect}) do
@@ -91,6 +94,7 @@ def #{method_name}(#{args})
             end
             #{visibility} :#{method_name}
           RUBY
+          # rubocop:enable Style/DocumentDynamicEvalDefinition
         end
       end
 
diff --git a/lib/airbrake/rack/route_filter.rb b/lib/airbrake/rack/route_filter.rb
index e531fae50..dc2b1cfd4 100644
--- a/lib/airbrake/rack/route_filter.rb
+++ b/lib/airbrake/rack/route_filter.rb
@@ -35,7 +35,7 @@ def rails_route(request)
       def sinatra_route(request)
         return unless (route = request.env['sinatra.route'])
 
-        route.split(' ').drop(1).join(' ')
+        route.split.drop(1).join(' ')
       end
 
       def action_dispatch_request?(request)
diff --git a/lib/airbrake/rails.rb b/lib/airbrake/rails.rb
index cc5bd26a6..24d3200e9 100644
--- a/lib/airbrake/rails.rb
+++ b/lib/airbrake/rails.rb
@@ -11,7 +11,7 @@ def self.logger
       level = (::Rails.logger ? ::Rails.logger.level : Logger::ERROR)
 
       if ENV['RAILS_LOG_TO_STDOUT'].present?
-        Logger.new(STDOUT, level: level)
+        Logger.new($stdout, level: level)
       else
         Logger.new(::Rails.root.join('log', 'airbrake.log'), level: level)
       end
diff --git a/lib/airbrake/rails/app.rb b/lib/airbrake/rails/app.rb
index 89cfb1e38..2bbec8639 100644
--- a/lib/airbrake/rails/app.rb
+++ b/lib/airbrake/rails/app.rb
@@ -40,12 +40,12 @@ def self.recognize_route(request)
             # Skip "catch-all" routes such as:
             #   get '*path => 'pages#about'
             #
-            # @todo The `glob?` method was added in Rails v4.2.0.beta1. We
-            # should remove the `respond_to?` check once we drop old Rails
-            # versions support.
+            # Ideally, we should be using `route.glob?` but in Rails 7+ this
+            # call would fail with a `NoMethodError`. This is because in
+            # Rails 7+ the AST for the route is not kept in memory anymore.
             #
-            # https://github.com/rails/rails/commit/5460591f0226a9d248b7b4f89186bd5553e7768f
-            next if route.respond_to?(:glob?) && route.glob?
+            # See: https://github.com/rails/rails/pull/43006#discussion_r783895766
+            next if route.path.spec.any?(ActionDispatch::Journey::Nodes::Star)
 
             path =
               if engine == ::Rails.application
diff --git a/lib/airbrake/rails/event.rb b/lib/airbrake/rails/event.rb
index 793106b76..47063c20b 100644
--- a/lib/airbrake/rails/event.rb
+++ b/lib/airbrake/rails/event.rb
@@ -10,10 +10,14 @@ class Event
       # @see https://github.com/rails/rails/issues/8987
       HTML_RESPONSE_WILDCARD = "*/*"
 
+      # @return [Integer]
+      MILLISECOND = 1000
+
       include Airbrake::Loggable
 
       def initialize(*args)
         @event = ActiveSupport::Notifications::Event.new(*args)
+        @rails_7_or_greater = ::Rails::VERSION::MAJOR >= 7
       end
 
       def method
@@ -42,7 +46,15 @@ def view_runtime
       end
 
       def time
-        @event.time
+        # On Rails 7+ `ActiveSupport::Notifications::Event#time` returns an
+        # instance of Float. It represents monotonic time in milliseconds.
+        # Airbrake Ruby expects that the provided time is in seconds. Hence,
+        # we need to convert it from milliseconds to seconds. In the
+        # versions below Rails 7, time is an instance of Time.
+        #
+        # Relevant commit:
+        # https://github.com/rails/rails/commit/81d0dc90becfe0b8e7f7f26beb66c25d84b8ec7f
+        @rails_7_or_greater ? @event.time / MILLISECOND : @event.time
       end
 
       def groups
diff --git a/lib/airbrake/rails/railtie.rb b/lib/airbrake/rails/railtie.rb
index d3feb7a0c..586f37ba3 100644
--- a/lib/airbrake/rails/railtie.rb
+++ b/lib/airbrake/rails/railtie.rb
@@ -5,37 +5,10 @@ module Rails
     # This railtie works for any Rails application that supports railties (Rails
     # 3.2+ apps). It makes Airbrake Ruby work with Rails and report errors
     # occurring in the application automatically.
-    #
-    # rubocop:disable Metrics/BlockLength
     class Railtie < ::Rails::Railtie
       initializer('airbrake.middleware') do |app|
-        # Since Rails 3.2 the ActionDispatch::DebugExceptions middleware is
-        # responsible for logging exceptions and showing a debugging page in
-        # case the request is local. We want to insert our middleware after
-        # DebugExceptions, so we don't notify Airbrake about local requests.
-
-        if ::Rails.version.to_i >= 5
-          # Avoid the warning about deprecated strings.
-          # Insert after DebugExceptions, since ConnectionManagement doesn't
-          # exist in Rails 5 anymore.
-          app.config.middleware.insert_after(
-            ActionDispatch::DebugExceptions,
-            Airbrake::Rack::Middleware,
-          )
-        elsif defined?(::ActiveRecord::ConnectionAdapters::ConnectionManagement)
-          # Insert after ConnectionManagement to avoid DB connection leakage:
-          # https://github.com/airbrake/airbrake/pull/568
-          app.config.middleware.insert_after(
-            ::ActiveRecord::ConnectionAdapters::ConnectionManagement,
-            'Airbrake::Rack::Middleware',
-          )
-        else
-          # Insert after DebugExceptions for apps without ActiveRecord.
-          app.config.middleware.insert_after(
-            ActionDispatch::DebugExceptions,
-            'Airbrake::Rack::Middleware',
-          )
-        end
+        require 'airbrake/rails/railties/middleware_tie'
+        Railties::MiddlewareTie.new(app).call
       end
 
       rake_tasks do
@@ -47,82 +20,13 @@ class Railtie < ::Rails::Railtie
       end
 
       initializer('airbrake.action_controller') do
-        ActiveSupport.on_load(:action_controller, run_once: true) do
-          # Patches ActionController with methods that allow us to retrieve
-          # interesting request data. Appends that information to notices.
-          require 'airbrake/rails/action_controller'
-          include Airbrake::Rails::ActionController
-
-          # Cache route information for the duration of the request.
-          require 'airbrake/rails/action_controller_route_subscriber'
-          ActiveSupport::Notifications.subscribe(
-            'start_processing.action_controller',
-            Airbrake::Rails::ActionControllerRouteSubscriber.new,
-          )
-
-          # Send route stats.
-          require 'airbrake/rails/action_controller_notify_subscriber'
-          ActiveSupport::Notifications.subscribe(
-            'process_action.action_controller',
-            Airbrake::Rails::ActionControllerNotifySubscriber.new,
-          )
-
-          # Send performance breakdown: where a request spends its time.
-          require 'airbrake/rails/action_controller_performance_breakdown_subscriber'
-          ActiveSupport::Notifications.subscribe(
-            'process_action.action_controller',
-            Airbrake::Rails::ActionControllerPerformanceBreakdownSubscriber.new,
-          )
-
-          require 'airbrake/rails/net_http' if defined?(Net) && defined?(Net::HTTP)
-          require 'airbrake/rails/curb' if defined?(Curl) && defined?(Curl::CURB_VERSION)
-          require 'airbrake/rails/http' if defined?(HTTP) && defined?(HTTP::Client)
-          require 'airbrake/rails/http_client' if defined?(HTTPClient)
-          require 'airbrake/rails/typhoeus' if defined?(Typhoeus)
-
-          if defined?(Excon)
-            require 'airbrake/rails/excon_subscriber'
-            ActiveSupport::Notifications.subscribe(/excon/, Airbrake::Rails::Excon.new)
-            ::Excon.defaults[:instrumentor] = ActiveSupport::Notifications
-          end
-        end
+        require 'airbrake/rails/railties/action_controller_tie'
+        Railties::ActionControllerTie.new.call
       end
 
       initializer('airbrake.active_record') do
-        ActiveSupport.on_load(:active_record, run_once: true) do
-          # Reports exceptions occurring in some bugged ActiveRecord callbacks.
-          # Applicable only to the versions of Rails lower than 4.2.
-          if defined?(::Rails) &&
-             Gem::Version.new(::Rails.version) <= Gem::Version.new('4.2')
-            require 'airbrake/rails/active_record'
-            include Airbrake::Rails::ActiveRecord
-          end
-
-          if defined?(ActiveRecord)
-            # Send SQL queries.
-            require 'airbrake/rails/active_record_subscriber'
-            ActiveSupport::Notifications.subscribe(
-              'sql.active_record', Airbrake::Rails::ActiveRecordSubscriber.new
-            )
-
-            # Filter out parameters from SQL body.
-            if ::ActiveRecord::Base.respond_to?(:connection_db_config)
-              # Rails 6.1+ deprecates "connection_config" in favor of
-              # "connection_db_config", so we need an updated call.
-              Airbrake.add_performance_filter(
-                Airbrake::Filters::SqlFilter.new(
-                  ::ActiveRecord::Base.connection_db_config.configuration_hash[:adapter],
-                ),
-              )
-            else
-              Airbrake.add_performance_filter(
-                Airbrake::Filters::SqlFilter.new(
-                  ::ActiveRecord::Base.connection_config[:adapter],
-                ),
-              )
-            end
-          end
-        end
+        require 'airbrake/rails/railties/active_record_tie'
+        Railties::ActiveRecordTie.new.call
       end
 
       initializer('airbrake.active_job') do
@@ -146,6 +50,5 @@ class Railtie < ::Rails::Railtie
         end
       end
     end
-    # rubocop:enable Metrics/BlockLength
   end
 end
diff --git a/lib/airbrake/rails/railties/action_controller_tie.rb b/lib/airbrake/rails/railties/action_controller_tie.rb
new file mode 100644
index 000000000..bc050fde9
--- /dev/null
+++ b/lib/airbrake/rails/railties/action_controller_tie.rb
@@ -0,0 +1,90 @@
+# frozen_string_literal: true
+
+require 'airbrake/rails/action_controller'
+require 'airbrake/rails/action_controller_route_subscriber'
+require 'airbrake/rails/action_controller_notify_subscriber'
+require 'airbrake/rails/action_controller_performance_breakdown_subscriber'
+
+module Airbrake
+  module Rails
+    module Railties
+      # Ties Airbrake APM (routes) and HTTP clients with Rails.
+      #
+      # @api private
+      # @since v13.0.1
+      class ActionControllerTie
+        def initialize
+          @route_subscriber = Airbrake::Rails::ActionControllerRouteSubscriber.new
+          @notify_subscriber = Airbrake::Rails::ActionControllerNotifySubscriber.new
+          @performance_breakdown_subscriber =
+            Airbrake::Rails::ActionControllerPerformanceBreakdownSubscriber.new
+        end
+
+        def call
+          ActiveSupport.on_load(:action_controller, run_once: true, yield: self) do
+            # Patches ActionController with methods that allow us to retrieve
+            # interesting request data. Appends that information to notices.
+            ::ActionController::Base.include(Airbrake::Rails::ActionController)
+
+            tie_routes_apm
+            tie_http_integrations
+          end
+        end
+
+        private
+
+        def tie_routes_apm
+          [
+            # Cache route information for the duration of the request.
+            ['start_processing.action_controller', @route_subscriber],
+
+            # Send route stats.
+            ['process_action.action_controller', @notify_subscriber],
+
+            # Send performance breakdown: where a request spends its time.
+            ['process_action.action_controller', @performance_breakdown_subscriber],
+          ].each do |(event, callback)|
+            ActiveSupport::Notifications.subscribe(event, callback)
+          end
+        end
+
+        def tie_http_integrations
+          tie_net_http
+          tie_curl
+          tie_http
+          tie_http_client
+          tie_typhoeus
+          tie_excon
+        end
+
+        def tie_net_http
+          require 'airbrake/rails/net_http' if defined?(Net) && defined?(Net::HTTP)
+        end
+
+        def tie_curl
+          require 'airbrake/rails/curb' if defined?(Curl) && defined?(Curl::CURB_VERSION)
+        end
+
+        def tie_http
+          require 'airbrake/rails/http' if defined?(HTTP) && defined?(HTTP::Client)
+        end
+
+        def tie_http_client
+          require 'airbrake/rails/http_client' if defined?(HTTPClient)
+        end
+
+        def tie_typhoeus
+          require 'airbrake/rails/typhoeus' if defined?(Typhoeus)
+        end
+
+        def tie_excon
+          return unless defined?(Excon)
+
+          require 'airbrake/rails/excon_subscriber'
+          ActiveSupport::Notifications.subscribe(/excon/, Airbrake::Rails::Excon.new)
+          ::Excon.defaults[:instrumentor] = ActiveSupport::Notifications
+        end
+      end
+    end
+  end
+end
diff --git a/lib/airbrake/rails/railties/active_record_tie.rb b/lib/airbrake/rails/railties/active_record_tie.rb
new file mode 100644
index 000000000..78bd20369
--- /dev/null
+++ b/lib/airbrake/rails/railties/active_record_tie.rb
@@ -0,0 +1,74 @@
+# frozen_string_literal: true
+
+require 'airbrake/rails/active_record'
+require 'airbrake/rails/active_record_subscriber'
+
+module Airbrake
+  module Rails
+    module Railties
+      # Ties Airbrake APM (queries) with Rails.
+      #
+      # @api private
+      # @since v13.0.1
+      class ActiveRecordTie
+        def initialize
+          @active_record_subscriber = Airbrake::Rails::ActiveRecordSubscriber.new
+        end
+
+        def call
+          ActiveSupport.on_load(:active_record, run_once: true, yield: self) do
+            tie_activerecord_callback_fix
+            tie_activerecord_apm
+          end
+        end
+
+        private
+
+        def tie_activerecord_callback_fix
+          # Reports exceptions occurring in some bugged ActiveRecord callbacks.
+          # Applicable only to the versions of Rails lower than 4.2.
+          return unless defined?(::Rails)
+          return if Gem::Version.new(::Rails.version) > Gem::Version.new('4.2')
+
+          ActiveRecord::Base.include(Airbrake::Rails::ActiveRecord)
+        end
+
+        def tie_activerecord_apm
+          # Some Rails apps don't use ActiveRecord.
+          return unless defined?(::ActiveRecord)
+
+          # However, some dependencies might still require it, so we need an
+          # extra check. Apps that don't need ActiveRecord will likely have no
+          # AR configurations defined. We will skip APM integration in that
+          # case. See: https://github.com/airbrake/airbrake/issues/1222
+          configurations = ::ActiveRecord::Base.configurations
+          return unless configurations.any?
+
+          # Send SQL queries.
+          ActiveSupport::Notifications.subscribe(
+            'sql.active_record',
+            @active_record_subscriber,
+          )
+
+          # Filter out parameters from SQL body.
+          sql_filter = Airbrake::Filters::SqlFilter.new(
+            detect_activerecord_adapter(configurations),
+          )
+          Airbrake.add_performance_filter(sql_filter)
+        end
+
+        # Rails 6+ introduces the `configs_for` API instead of the deprecated
+        # `#[]`, so we need an updated call.
+        def detect_activerecord_adapter(configurations)
+          unless configurations.respond_to?(:configs_for)
+            return configurations[::Rails.env]['adapter']
+          end
+
+          cfg = configurations.configs_for(env_name: ::Rails.env).first
+          # Rails 7+ API : Rails 6 API.
+          cfg.respond_to?(:adapter) ? cfg.adapter : cfg.config['adapter']
+        end
+      end
+    end
+  end
+end
diff --git a/lib/airbrake/rails/railties/middleware_tie.rb b/lib/airbrake/rails/railties/middleware_tie.rb
new file mode 100644
index 000000000..3c5bee8d1
--- /dev/null
+++ b/lib/airbrake/rails/railties/middleware_tie.rb
@@ -0,0 +1,62 @@
+# frozen_string_literal: true
+
+module Airbrake
+  module Rails
+    module Railties
+      # Ties Airbrake Rails Middleware with Rails (error sending).
+      #
+      # Since Rails 3.2 the ActionDispatch::DebugExceptions middleware is
+      # responsible for logging exceptions and showing a debugging page in case
+      # the request is local. We want to insert our middleware after
+      # DebugExceptions, so we don't notify Airbrake about local requests.
+      #
+      # @api private
+      # @since v13.0.1
+      class MiddlewareTie
+        def initialize(app)
+          @app = app
+          @middleware = app.config.middleware
+        end
+
+        def call
+          return tie_rails_5_or_above if ::Rails.version.to_i >= 5
+
+          if defined?(::ActiveRecord::ConnectionAdapters::ConnectionManagement)
+            return tie_rails_4_or_below_with_active_record
+          end
+
+          tie_rails_4_or_below_with_active_record
+        end
+
+        private
+
+        # Avoid the warning about deprecated strings.
+        # Insert after DebugExceptions, since ConnectionManagement doesn't
+        # exist in Rails 5 anymore.
+        def tie_rails_5_or_above
+          @middleware.insert_after(
+            ActionDispatch::DebugExceptions,
+            Airbrake::Rack::Middleware,
+          )
+        end
+
+        # Insert after ConnectionManagement to avoid DB connection leakage:
+        # https://github.com/airbrake/airbrake/pull/568
+        def tie_rails_4_or_below_with_active_record
+          @middleware.insert_after(
+            ::ActiveRecord::ConnectionAdapters::ConnectionManagement,
+            'Airbrake::Rack::Middleware',
+          )
+        end
+
+        # Insert after DebugExceptions for apps without ActiveRecord.
+        def tie_rails_4_or_below_without_active_record
+          @middleware.insert_after(
+            ActionDispatch::DebugExceptions,
+            'Airbrake::Rack::Middleware',
+          )
+        end
+      end
+    end
+  end
+end
diff --git a/lib/airbrake/rake/tasks.rb b/lib/airbrake/rake/tasks.rb
index 0de505416..b4eef44e8 100644
--- a/lib/airbrake/rake/tasks.rb
+++ b/lib/airbrake/rake/tasks.rb
@@ -53,11 +53,11 @@
     raise Airbrake::Error, 'airbrake-ruby is not configured' unless Airbrake.configured?
 
     deploy_params = {
-      environment: ENV['ENVIRONMENT'],
-      username: ENV['USERNAME'],
-      revision: ENV['REVISION'],
-      repository: ENV['REPOSITORY'],
-      version: ENV['VERSION'],
+      environment: ENV.fetch('ENVIRONMENT', nil),
+      username: ENV.fetch('USERNAME', nil),
+      revision: ENV.fetch('REVISION', nil),
+      repository: ENV.fetch('REPOSITORY', nil),
+      version: ENV.fetch('VERSION', nil),
     }
     promise = Airbrake.notify_deploy(deploy_params)
     promise.then do
@@ -68,7 +68,7 @@
 
   desc 'Install a Heroku deploy hook to notify Airbrake of deploys'
   task :install_heroku_deploy_hook do
-    app = ENV['HEROKU_APP']
+    app = ENV.fetch('HEROKU_APP', nil)
 
     config = Bundler.with_clean_env do
       `heroku config --shell#{" --app #{app}" if app}`
@@ -89,7 +89,7 @@
            " environment will be used."
     end
 
-    unless (repo = ENV['REPOSITORY_URL'])
+    unless (repo = ENV.fetch('REPOSITORY_URL', nil))
       repo = `git remote get-url origin 2>/dev/null`.chomp
       if repo.empty?
         puts "Airbrake couldn't identify your app's repository."
diff --git a/lib/airbrake/shoryuken.rb b/lib/airbrake/shoryuken.rb
index 03d3c02d5..e86ae42b6 100644
--- a/lib/airbrake/shoryuken.rb
+++ b/lib/airbrake/shoryuken.rb
@@ -5,10 +5,8 @@ module Shoryuken
     # Provides integration with Shoryuken.
     class ErrorHandler
       # rubocop:disable Lint/RescueException
-      def call(worker, queue, _sqs_msg, body)
-        timing = Airbrake::Benchmark.measure do
-          yield
-        end
+      def call(worker, queue, _sqs_msg, body, &block)
+        timing = Airbrake::Benchmark.measure(&block)
       rescue Exception => exception
         notify_airbrake(exception, worker, queue, body)
         Airbrake.notify_queue(
diff --git a/lib/airbrake/sidekiq.rb b/lib/airbrake/sidekiq.rb
index 05c1c96fb..0f088a296 100644
--- a/lib/airbrake/sidekiq.rb
+++ b/lib/airbrake/sidekiq.rb
@@ -6,10 +6,8 @@ module Airbrake
   module Sidekiq
     # Provides integration with Sidekiq v2+.
     class ErrorHandler
-      def call(_worker, context, _queue)
-        timing = Airbrake::Benchmark.measure do
-          yield
-        end
+      def call(_worker, context, _queue, &block)
+        timing = Airbrake::Benchmark.measure(&block)
       rescue Exception => exception # rubocop:disable Lint/RescueException
         notify_airbrake(exception, context)
         Airbrake.notify_queue(
@@ -38,7 +36,7 @@ def notify_airbrake(exception, context)
       # @return [String] job's name. When ActiveJob is present, retrieve
       #   job_class. When used directly, use worker's name
       def action(context)
-        klass = context['class'] || context[:job] && context[:job]['class']
+        klass = context['class'] || (context[:job] && context[:job]['class'])
         return klass unless context[:job] && context[:job]['args'].first.is_a?(Hash)
         return klass unless (job_class = context[:job]['args'].first['job_class'])
 
diff --git a/lib/airbrake/sneakers.rb b/lib/airbrake/sneakers.rb
index 035b7a72d..7d4e22bad 100644
--- a/lib/airbrake/sneakers.rb
+++ b/lib/airbrake/sneakers.rb
@@ -48,24 +48,22 @@ module Worker
       define_method(
         ::Sneakers::Worker.method_defined?(:process_work) ? :process_work : :do_work,
       ) do |delivery_info, metadata, msg, handler|
-        begin
-          timing = Airbrake::Benchmark.measure do
-            super(delivery_info, metadata, msg, handler)
-          end
-        rescue Exception => exception # rubocop:disable Lint/RescueException
-          Airbrake.notify_queue(
-            queue: self.class.to_s,
-            error_count: 1,
-            timing: 0.01,
-          )
-          raise exception
-        else
-          Airbrake.notify_queue(
-            queue: self.class.to_s,
-            error_count: 0,
-            timing: timing,
-          )
+        timing = Airbrake::Benchmark.measure do
+          super(delivery_info, metadata, msg, handler)
         end
+      rescue Exception => exception # rubocop:disable Lint/RescueException
+        Airbrake.notify_queue(
+          queue: self.class.to_s,
+          error_count: 1,
+          timing: 0.01,
+        )
+        raise exception
+      else
+        Airbrake.notify_queue(
+          queue: self.class.to_s,
+          error_count: 0,
+          timing: timing,
+        )
       end
     end
   end
diff --git a/lib/airbrake/version.rb b/lib/airbrake/version.rb
index 05796c8b3..df319d852 100644
--- a/lib/airbrake/version.rb
+++ b/lib/airbrake/version.rb
@@ -3,5 +3,5 @@
 # We use Semantic Versioning v2.0.0
 # More information: http://semver.org/
 module Airbrake
-  AIRBRAKE_VERSION = '11.0.3'
+  AIRBRAKE_VERSION = '13.0.2'
 end
diff --git a/lib/generators/airbrake_generator.rb b/lib/generators/airbrake_generator.rb
index afb3f5b3c..1b1e252f1 100644
--- a/lib/generators/airbrake_generator.rb
+++ b/lib/generators/airbrake_generator.rb
@@ -3,22 +3,19 @@
 # Creates the Airbrake initializer file for Rails apps.
 #
 # @example Invokation from terminal
-#   rails generate airbrake PROJECT_KEY PROJECT_ID [NAME]
+#   rails generate airbrake [NAME]
 #
 class AirbrakeGenerator < Rails::Generators::Base
   # Adds current directory to source paths, so we can find the template file.
   source_root File.expand_path(__dir__)
 
-  argument :project_id, required: false
-  argument :project_key, required: false
-
   # Makes the NAME option optional, which allows to subclass from Base, so we
   # can pass arguments to the ERB template.
   #
-  # @see http://asciicasts.com/episodes/218-making-generators-in-rails-3
+  # @see https://asciicasts.com/episodes/218-making-generators-in-rails-3.html
   argument :name, type: :string, default: 'application'
 
-  desc 'Configures the Airbrake notifier with your project id and project key'
+  desc 'Configures the Airbrake notifier'
   def generate_layout
     template 'airbrake_initializer.rb.erb', 'config/initializers/airbrake.rb'
   end
diff --git a/lib/generators/airbrake_initializer.rb.erb b/lib/generators/airbrake_initializer.rb.erb
index 3f43d32f5..23c83eafc 100644
--- a/lib/generators/airbrake_initializer.rb.erb
+++ b/lib/generators/airbrake_initializer.rb.erb
@@ -1,80 +1,80 @@
 # frozen_string_literal: true
 
-# Airbrake is an online tool that provides robust exception tracking in your Rails
-# applications. In doing so, it allows you to easily review errors, tie an error
-# to an individual piece of code, and trace the cause back to recent
-# changes. Airbrake enables for easy categorization, searching, and prioritization
-# of exceptions so that when errors occur, your team can quickly determine the
-# root cause.
+# Airbrake is an online tool that provides robust exception tracking in your
+# Rails applications. In doing so, it allows you to easily review errors, tie an
+# error to an individual piece of code, and trace the cause back to recent
+# changes. Airbrake enables for easy categorization, searching, and
+# prioritization of exceptions so that when errors occur, your team can quickly
+# determine the root cause.
 #
 # Configuration details:
 # https://github.com/airbrake/airbrake-ruby#configuration
-Airbrake.configure do |c|
-  # You must set both project_id & project_key. To find your project_id and
-  # project_key navigate to your project's General Settings and copy the values
-  # from the right sidebar.
-  # https://github.com/airbrake/airbrake-ruby#project_id--project_key
-<% if project_id -%>
-  c.project_id = <%= project_id %>
-<% else -%>
-  c.project_id = ENV['AIRBRAKE_PROJECT_ID']
-<% end -%>
-<% if project_key -%>
-  c.project_key = '<%= project_key %>'
-<% else -%>
-  c.project_key = ENV['AIRBRAKE_API_KEY']
-<% end -%>
+if (project_id = ENV['AIRBRAKE_PROJECT_ID']) &&
+   project_key = (ENV['AIRBRAKE_PROJECT_KEY'] || ENV['AIRBRAKE_API_KEY'])
+  Airbrake.configure do |c|
+    # You must set both project_id & project_key. To find your project_id and
+    # project_key navigate to your project's General Settings and copy the
+    # values from the right sidebar.
+    # https://github.com/airbrake/airbrake-ruby#project_id--project_key
+    c.project_id = project_id
+    c.project_key = project_key
 
-  # Configures the root directory of your project. Expects a String or a
-  # Pathname, which represents the path to your project. Providing this option
-  # helps us to filter out repetitive data from backtrace frames and link to
-  # GitHub files from our dashboard.
-  # https://github.com/airbrake/airbrake-ruby#root_directory
-  c.root_directory = Rails.root
+    # Configures the root directory of your project. Expects a String or a
+    # Pathname, which represents the path to your project. Providing this option
+    # helps us to filter out repetitive data from backtrace frames and link to
+    # GitHub files from our dashboard.
+    # https://github.com/airbrake/airbrake-ruby#root_directory
+    c.root_directory = Rails.root
 
-  # By default, Airbrake Ruby outputs to STDOUT. In Rails apps it makes sense to
-  # use the Rails' logger.
-  # https://github.com/airbrake/airbrake-ruby#logger
-  c.logger = Airbrake::Rails.logger
+    # By default, Airbrake Ruby outputs to STDOUT. In Rails apps it makes sense
+    # to use the Rails' logger.
+    # https://github.com/airbrake/airbrake-ruby#logger
+    c.logger = Airbrake::Rails.logger
 
-  # Configures the environment the application is running in. Helps the Airbrake
-  # dashboard to distinguish between exceptions occurring in different
-  # environments.
-  # NOTE: This option must be set in order to make the 'ignore_environments'
-  # option work.
-  # https://github.com/airbrake/airbrake-ruby#environment
-  c.environment = Rails.env
+    # Configures the environment the application is running in. Helps the
+    # Airbrake dashboard to distinguish between exceptions occurring in
+    # different environments.
+    # NOTE: This option must be set in order to make the 'ignore_environments'
+    # option work.
+    # https://github.com/airbrake/airbrake-ruby#environment
+    c.environment = Rails.env
 
-  # Setting this option allows Airbrake to filter exceptions occurring in
-  # unwanted environments such as :test.
-  # NOTE: This option *does not* work if you don't set the 'environment' option.
-  # https://github.com/airbrake/airbrake-ruby#ignore_environments
-  c.ignore_environments = %w[test]
+    # Setting this option allows Airbrake to filter exceptions occurring in
+    # unwanted environments such as :test.  NOTE: This option *does not* work if
+    # you don't set the 'environment' option.
+    # https://github.com/airbrake/airbrake-ruby#ignore_environments
+    c.ignore_environments = %w[test]
 
-  # A list of parameters that should be filtered out of what is sent to
-  # Airbrake. By default, all "password" attributes will have their contents
-  # replaced.
-  # https://github.com/airbrake/airbrake-ruby#blocklist_keys
-  c.blocklist_keys = [/password/i, /authorization/i]
+    # A list of parameters that should be filtered out of what is sent to
+    # Airbrake. By default, all "password" attributes will have their contents
+    # replaced.
+    # https://github.com/airbrake/airbrake-ruby#blocklist_keys
+    c.blocklist_keys = [/password/i, /authorization/i]
 
-  # Alternatively, you can integrate with Rails' filter_parameters.
-  # Read more: https://goo.gl/gqQ1xS
-  # c.blocklist_keys = Rails.application.config.filter_parameters
-end
+    # Alternatively, you can integrate with Rails' filter_parameters.
+    # Read more: https://goo.gl/gqQ1xS
+    # c.blocklist_keys = Rails.application.config.filter_parameters
+  end
 
-# A filter that collects request body information. Enable it if you are sure you
-# don't send sensitive information to Airbrake in your body (such as passwords).
-# https://github.com/airbrake/airbrake#requestbodyfilter
-# Airbrake.add_filter(Airbrake::Rack::RequestBodyFilter.new)
+  # A filter that collects request body information. Enable it if you are sure you
+  # don't send sensitive information to Airbrake in your body (such as passwords).
+  # https://github.com/airbrake/airbrake#requestbodyfilter
+  # Airbrake.add_filter(Airbrake::Rack::RequestBodyFilter.new)
 
-# Attaches thread & fiber local variables along with general thread information.
-# Airbrake.add_filter(Airbrake::Filters::ThreadFilter.new)
+  # Attaches thread & fiber local variables along with general thread information.
+  # Airbrake.add_filter(Airbrake::Filters::ThreadFilter.new)
 
-# Attaches loaded dependencies to the notice object
-# (under context/versions/dependencies).
-# Airbrake.add_filter(Airbrake::Filters::DependencyFilter.new)
+  # Attaches loaded dependencies to the notice object
+  # (under context/versions/dependencies).
+  # Airbrake.add_filter(Airbrake::Filters::DependencyFilter.new)
 
-# If you want to convert your log messages to Airbrake errors, we offer an
-# integration with the Logger class from stdlib.
-# https://github.com/airbrake/airbrake#logger
-# Rails.logger = Airbrake::AirbrakeLogger.new(Rails.logger)
+  # If you want to convert your log messages to Airbrake errors, we offer an
+  # integration with the Logger class from stdlib.
+  # https://github.com/airbrake/airbrake#logger
+  # Rails.logger = Airbrake::AirbrakeLogger.new(Rails.logger)
+else
+  Rails.logger.warn(
+    "#{__FILE__}: Airbrake project id or project key is not set. " \
+    "Skipping Airbrake configuration"
+  )
+end
diff --git a/spec/apps/rack/dummy_app.rb b/spec/apps/rack/rack_app.rb
similarity index 91%
rename from spec/apps/rack/dummy_app.rb
rename to spec/apps/rack/rack_app.rb
index a3e6f2605..4ee0f4129 100644
--- a/spec/apps/rack/dummy_app.rb
+++ b/spec/apps/rack/rack_app.rb
@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-DummyApp = Rack::Builder.new do
+RackApp = Rack::Builder.new do
   use Rack::ShowExceptions
   use Airbrake::Rack::Middleware
   use Warden::Manager
diff --git a/spec/apps/rails/dummy_app.rb b/spec/apps/rails/dummy_app.rb
index 538408245..36e396e2d 100644
--- a/spec/apps/rails/dummy_app.rb
+++ b/spec/apps/rails/dummy_app.rb
@@ -10,7 +10,7 @@ class DummyApp < Rails::Application
   config.secret_key_base = '62773890cad9d9d584b57320f8612f8f7378a90aadcabc6ee'
 
   # Configure a logger, without it the tests can't run.
-  vsn = Rails.version.split('').values_at(0, 2).join('')
+  vsn = Rails.version.chars.values_at(0, 2).join
   log_path = File.join(File.dirname(__FILE__), 'logs', "#{vsn}.log")
   config.logger = Logger.new(log_path)
   Rails.logger = config.logger
@@ -73,21 +73,18 @@ def raise_error_after_rollback
   end
 end
 
-# ActiveJob.
-if Gem::Version.new(Rails.version) >= Gem::Version.new('4.2')
-  class BingoJob < ActiveJob::Base
-    queue_as :bingo
+class BingoJob < ActiveJob::Base
+  queue_as :bingo
 
-    class BingoWrapper
-      def initialize(bingo)
-        @bingo = bingo
-      end
+  class BingoWrapper
+    def initialize(bingo)
+      @bingo = bingo
     end
+  end
 
-    def perform(*_args)
-      @wrapper = BingoWrapper.new(self)
-      raise AirbrakeTestError, 'active_job error'
-    end
+  def perform(*_args)
+    @wrapper = BingoWrapper.new(self)
+    raise AirbrakeTestError, 'active_job error'
   end
 end
 
@@ -147,47 +144,47 @@ def breakdown
   end
 
   def breakdown_view_only
-    render 'dummy/breakdown.html.erb'
+    render 'dummy/breakdown', format: [:erb]
   end
 
   def breakdown_http
     Net::HTTP.get('example.com', '/')
-    render 'dummy/breakdown_http.html.erb'
+    render 'dummy/breakdown_http', format: [:erb]
   end
 
   def breakdown_curl_http
     Curl.get('example.com')
-    render 'dummy/breakdown_curl_http.html.erb'
+    render 'dummy/breakdown_curl_http', format: [:erb]
   end
 
   def breakdown_curl_http_easy
     Curl::Easy.perform('example.com')
-    render 'dummy/breakdown_curl_http_easy.html.erb'
+    render 'dummy/breakdown_curl_http_easy', format: [:erb]
   end
 
   def breakdown_curl_http_multi
     Curl::Multi.get(['example.com'])
-    render 'dummy/breakdown_curl_http_multi.html.erb'
+    render 'dummy/breakdown_curl_http_multi', format: [:erb]
   end
 
   def breakdown_excon
     Excon.get('http://example.com')
-    render 'dummy/breakdown_excon.html.erb'
+    render 'dummy/breakdown_excon', format: [:erb]
   end
 
   def breakdown_http_rb
     HTTP.get('http://example.com')
-    render 'dummy/breakdown_http_rb.html.erb'
+    render 'dummy/breakdown_http_rb', format: [:erb]
   end
 
   def breakdown_http_client
     HTTPClient.new.get('http://example.com')
-    render 'dummy/breakdown_http_client.html.erb'
+    render 'dummy/breakdown_http_client', format: [:erb]
   end
 
   def breakdown_typhoeus
     Typhoeus.get('example.com')
-    render 'dummy/breakdown_typhoeus.html.erb'
+    render 'dummy/breakdown_typhoeus', format: [:erb]
   end
 
   def notify_airbrake_helper
@@ -234,8 +231,8 @@ def delayed_job
 # Modified version of: https://goo.gl/q8uCJq
 migration_template = File.open(
   File.join(
-    $LOAD_PATH.grep(/delayed_job/)[0],
-    'generators/delayed_job/templates/migration.rb',
+    $LOAD_PATH.grep(/delayed/)[0],
+    'generators/delayed/templates/migration.rb',
   ),
 )
 
diff --git a/spec/integration/rack/rack_spec.rb b/spec/integration/rack/rack_spec.rb
index 83a1107cf..52a57c6bd 100644
--- a/spec/integration/rack/rack_spec.rb
+++ b/spec/integration/rack/rack_spec.rb
@@ -3,7 +3,7 @@
 require 'integration/shared_examples/rack_examples'
 
 RSpec.describe "Rack integration specs" do
-  let(:app) { DummyApp }
+  let(:app) { RackApp }
 
   include_examples 'rack examples'
 
diff --git a/spec/integration/rails/rails_spec.rb b/spec/integration/rails/rails_spec.rb
index 762081dce..efbe6b0f1 100644
--- a/spec/integration/rails/rails_spec.rb
+++ b/spec/integration/rails/rails_spec.rb
@@ -64,11 +64,8 @@ def force_http_libs_prepend
 
   shared_examples "context payload content" do |route|
     let(:user) do
-      OpenStruct.new(
-        id: 1,
-        email: 'qa@example.com',
-        username: 'qa-dept',
-      )
+      stub_const('User', Struct.new(:id, :email, :username))
+      User.new(1, 'qa@example.com', 'qa-dept')
     end
 
     before do
@@ -108,7 +105,7 @@ def force_http_libs_prepend
     end
 
     it "includes params" do
-      action = route[1..-1]
+      action = route[1..]
       body = /"context":{.*"params":{.*"controller":"dummy","action":"#{action}".*}/
       expect(a_request(:post, endpoint).with(body: body)).to have_been_made
     end
@@ -223,11 +220,8 @@ def force_http_libs_prepend
   describe "user extraction" do
     context "when Warden is not available but 'current_user' is defined" do
       let(:user) do
-        OpenStruct.new(
-          id: 1,
-          email: 'qa@example.com',
-          username: 'qa-dept',
-        )
+        stub_const('User', Struct.new(:id, :email, :username))
+        User.new(1, 'qa@example.com', 'qa-dept')
       end
 
       before do
@@ -252,6 +246,7 @@ def force_http_libs_prepend
   describe "request performance hook" do
     before do
       allow(Airbrake).to receive(:notify)
+      allow(Airbrake).to receive(:notify_request)
       allow(config).to receive(:performance_stats).and_return(true)
     end
 
@@ -267,7 +262,7 @@ def force_http_libs_prepend
 
     it "defaults to 500 when status code for exception returns 0" do
       allow(ActionDispatch::ExceptionWrapper)
-        .to receive(:status_code_for_exception).and_return(0)
+        .to receive(:status_code).and_return(0)
 
       expect(Airbrake).to receive(:notify_request).with(
         hash_including(
@@ -278,6 +273,36 @@ def force_http_libs_prepend
       )
       head '/crash'
     end
+
+    context "when Rails version is below 7" do
+      before do
+        if Rails::VERSION::MAJOR >= 7
+          skip("This test requires Rails 6 or lower, you're on Rails #{Rails.version}")
+        end
+      end
+
+      it "reports time as an instance of Time" do
+        head '/crash'
+        expect(Airbrake).to have_received(:notify_request).with(
+          hash_including(time: an_instance_of(Time)),
+        )
+      end
+    end
+
+    context "when Rails version is 7+" do
+      before do
+        if Rails::VERSION::MAJOR < 7
+          skip("This test requires Rails 7+, you're on Rails #{Rails.version}")
+        end
+      end
+
+      it "reports time as an instance of Float" do
+        head '/crash'
+        expect(Airbrake).to have_received(:notify_request).with(
+          hash_including(time: an_instance_of(Float)),
+        )
+      end
+    end
   end
 
   describe "query performance hook" do
@@ -429,7 +454,7 @@ def force_http_libs_prepend
 
       it "includes the http breakdown" do
         expect(Airbrake).to receive(:notify_performance_breakdown).with(
-          hash_including(groups: { http: be > 0 }),
+          hash_including(groups: { view: be > 0, http: be > 0 }),
           an_instance_of(Hash),
         )
         get '/breakdown_excon'
@@ -444,7 +469,7 @@ def force_http_libs_prepend
 
       it "includes the http breakdown" do
         expect(Airbrake).to receive(:notify_performance_breakdown).with(
-          hash_including(groups: { http: be > 0 }),
+          hash_including(groups: { view: be > 0, http: be > 0 }),
           an_instance_of(Hash),
         )
         get '/breakdown_http_rb'
@@ -465,7 +490,7 @@ def force_http_libs_prepend
 
       it "includes the http breakdown" do
         expect(Airbrake).to receive(:notify_performance_breakdown).with(
-          hash_including(groups: { http: be > 0 }),
+          hash_including(groups: { view: be > 0, http: be > 0 }),
           an_instance_of(Hash),
         )
         get '/breakdown_http_client'
@@ -478,9 +503,16 @@ def force_http_libs_prepend
         stub_request(:get, 'http://example.com').to_return(body: '')
       end
 
+      before do
+        # On JRuby 9.2.19.0 this fails with a SIGSEGV in JVM:
+        # https://bit.ly/3Everoa
+        # This is somehow related to libcurl.so.
+        skip('SIGSEGV on JRuby 9.2.19.0') if Airbrake::JRUBY
+      end
+
       it "includes the http breakdown" do
         expect(Airbrake).to receive(:notify_performance_breakdown).with(
-          hash_including(groups: { http: be > 0 }),
+          hash_including(groups: { view: be > 0, http: be > 0 }),
           an_instance_of(Hash),
         )
         get '/breakdown_typhoeus'
@@ -490,7 +522,8 @@ def force_http_libs_prepend
 
     context "when current user is logged in" do
       let(:user) do
-        OpenStruct.new(id: 1, email: 'qa@example.com', username: 'qa-dept')
+        stub_const('User', Struct.new(:id, :email, :username))
+        User.new(1, 'qa@example.com', 'qa-dept')
       end
 
       before do
diff --git a/spec/integration/rails/rake_spec.rb b/spec/integration/rails/rake_spec.rb
index 85ef3578e..5bff56433 100644
--- a/spec/integration/rails/rake_spec.rb
+++ b/spec/integration/rails/rake_spec.rb
@@ -41,7 +41,7 @@
 
     it "includes a timestamp" do
       expected_notice = a_notice_with(
-        %i[params rake_task timestamp], /20\d\d\-\d\d-\d\d.+/
+        %i[params rake_task timestamp], /20\d\d-\d\d-\d\d.+/
       )
       expect(Airbrake).to receive(:notify_sync).with(expected_notice)
     end
diff --git a/spec/integration/shared_examples/rack_examples.rb b/spec/integration/shared_examples/rack_examples.rb
index 1925ef5ba..670e17f33 100644
--- a/spec/integration/shared_examples/rack_examples.rb
+++ b/spec/integration/shared_examples/rack_examples.rb
@@ -40,13 +40,8 @@
 
   describe "user payload" do
     let(:user) do
-      OpenStruct.new(
-        id: 1,
-        email: 'qa@example.com',
-        username: 'qa-dept',
-        first_name: 'John',
-        last_name: 'Doe',
-      )
+      stub_const('User', Struct.new(:id, :email, :username, :first_name, :last_name))
+      User.new(1, 'qa@example.com', 'qa-dept', 'John', 'Doe')
     end
 
     before { login_as(user) }
diff --git a/spec/integration/sinatra/sinatra_spec.rb b/spec/integration/sinatra/sinatra_spec.rb
index 632770a08..2fbc5e3e6 100644
--- a/spec/integration/sinatra/sinatra_spec.rb
+++ b/spec/integration/sinatra/sinatra_spec.rb
@@ -25,7 +25,7 @@
       get '/crash'
       sleep 2
 
-      body = %r("context":{.*"route":"\/crash".*})
+      body = %r("context":{.*"route":"/crash".*})
       expect(a_request(:post, endpoint).with(body: body)).to have_been_made
     end
   end
diff --git a/spec/spec_helper.rb b/spec/spec_helper.rb
index 6b3c274c2..4fe35e7ef 100644
--- a/spec/spec_helper.rb
+++ b/spec/spec_helper.rb
@@ -97,7 +97,7 @@
     # Don't load the Rack app since we want to test Sinatra if it's loaded.
     raise LoadError if defined?(Sinatra)
 
-    require 'apps/rack/dummy_app'
+    require 'apps/rack/rack_app'
   rescue LoadError
     puts '** Skipped Rack specs'
   end
diff --git a/spec/support/matchers/a_notice_with.rb b/spec/support/matchers/a_notice_with.rb
index 518c2869d..fb401d645 100644
--- a/spec/support/matchers/a_notice_with.rb
+++ b/spec/support/matchers/a_notice_with.rb
@@ -5,12 +5,7 @@
     payload = notice[access_keys.shift]
     break(false) unless payload
 
-    actual_val =
-      if payload.respond_to?(:dig)
-        payload.dig(*access_keys)
-      else
-        dig_pre_23(payload, *access_keys)
-      end
+    actual_val = payload.dig(*access_keys)
 
     if expected_val.is_a?(Regexp)
       actual_val =~ expected_val
@@ -18,15 +13,4 @@
       actual_val == expected_val
     end
   end
-
-  # TODO: Use the normal "dig" version once we support Ruby 2.3 and above.
-  def dig_pre_23(hash, *keys)
-    v = hash[keys.shift]
-    while keys.any?
-      return unless v.is_a?(Hash)
-
-      v = v[keys.shift]
-    end
-    v
-  end
 end
diff --git a/spec/unit/rack/instrumentable_spec.rb b/spec/unit/rack/instrumentable_spec.rb
index bc09f2288..ddaacd11d 100644
--- a/spec/unit/rack/instrumentable_spec.rb
+++ b/spec/unit/rack/instrumentable_spec.rb
@@ -36,12 +36,16 @@ def method_with!(val); end
         def method_with?(val); end
         airbrake_capture_timing :method_with?
 
+        # rubocop:disable Layout/EmptyLinesAroundAttributeAccessor
         attr_writer :method_with
         airbrake_capture_timing :method_with=
+        # rubocop:enable Layout/EmptyLinesAroundAttributeAccessor
 
+        # rubocop:disable Lint/UselessMethodDefinition
         def ==(other)
           super
         end
+        # rubocop:enable Lint/UselessMethodDefinition
         airbrake_capture_timing :==
 
         def method_with_block
@@ -65,25 +69,33 @@ def writer_with_everything=(a, b = nil, *args, foo:, bar: nil)
 
         prepend(
           Module.new do
+            # rubocop:disable Lint/UselessMethodDefinition
             def prepended_method!(*args, **kw_args)
               super
             end
+            # rubocop:enable Lint/UselessMethodDefinition
 
+            # rubocop:disable Lint/UselessMethodDefinition
             def prepended_writer=(*args, **kw_args)
               super
             end
+            # rubocop:enable Lint/UselessMethodDefinition
 
             protected
 
+            # rubocop:disable Lint/UselessMethodDefinition
             def a_prepended_protected_method
               super
             end
+            # rubocop:enable Lint/UselessMethodDefinition
 
             private
 
+            # rubocop:disable Lint/UselessMethodDefinition
             def a_prepended_private_method
               super
             end
+            # rubocop:enable Lint/UselessMethodDefinition
           end,
         )
 
@@ -236,12 +248,12 @@ def a_prepended_private_method; end
       end
 
       it "attaches timing for a method with all arg types" do
-        klass.new.send('method_with_everything!', 1, 2, 3, foo: 4, bar: 5) {}
+        klass.new.send('method_with_everything!', 1, 2, 3, foo: 4, bar: 5) { 1 }
         expect(groups).to match('method_with_everything!' => be > 0)
       end
 
       it "attaches timing for a writer method with all arg types" do
-        klass.new.send('writer_with_everything=', 1, 2, 3, foo: 4, bar: 5) {}
+        klass.new.send('writer_with_everything=', 1, 2, 3, foo: 4, bar: 5) { 1 }
         expect(groups).to match('writer_with_everything=' => be > 0)
       end
 
@@ -251,7 +263,7 @@ def a_prepended_private_method; end
       end
 
       it "attaches timing for a prepended writer method with all arg types" do
-        klass.new.send('prepended_writer=', 1, 2, 3, foo: 4, bar: 5) {}
+        klass.new.send('prepended_writer=', 1, 2, 3, foo: 4, bar: 5) { 1 }
         expect(groups).to match('prepended_writer=' => be > 0)
       end
 
diff --git a/spec/unit/rack/rack_spec.rb b/spec/unit/rack/rack_spec.rb
index c48806143..5549d3b67 100644
--- a/spec/unit/rack/rack_spec.rb
+++ b/spec/unit/rack/rack_spec.rb
@@ -8,7 +8,7 @@
 
     context "when request store doesn't have any routes" do
       it "doesn't store timing" do
-        described_class.capture_timing('operation') {}
+        described_class.capture_timing('operation') { 1 }
         expect(Airbrake::Rack::RequestStore.store).to be_empty
       end
 
@@ -39,9 +39,9 @@
         end
 
         it "doesn't attach any timings" do
-          described_class.capture_timing('operation 1') {}
-          described_class.capture_timing('operation 2') {}
-          described_class.capture_timing('operation 3') {}
+          described_class.capture_timing('operation 1') { 1 }
+          described_class.capture_timing('operation 2') { 2 }
+          described_class.capture_timing('operation 3') { 3 }
 
           expect(routes['/about'][:groups]).to be_empty
         end
@@ -54,9 +54,9 @@
         end
 
         it "attaches all timings for different operations to the request store" do
-          described_class.capture_timing('operation 1') {}
-          described_class.capture_timing('operation 2') {}
-          described_class.capture_timing('operation 3') {}
+          described_class.capture_timing('operation 1') { 1 }
+          described_class.capture_timing('operation 2') { 2 }
+          described_class.capture_timing('operation 3') { 3 }
 
           expect(routes['/about'][:groups]).to match(
             'operation 1' => be > 0,
diff --git a/spec/unit/rack/user_spec.rb b/spec/unit/rack/user_spec.rb
index db05fc150..11f2d73f5 100644
--- a/spec/unit/rack/user_spec.rb
+++ b/spec/unit/rack/user_spec.rb
@@ -4,13 +4,8 @@
   let(:endpoint) { 'https://api.airbrake.io/api/v3/projects/113743/notices' }
 
   let(:user) do
-    OpenStruct.new(
-      id: 1,
-      email: 'qa@example.com',
-      username: 'qa-dept',
-      first_name: 'Bingo',
-      last_name: 'Bongo',
-    )
+    stub_const('User', Struct.new(:id, :email, :username, :first_name, :last_name))
+    User.new(1, 'qa@example.com', 'qa-dept', 'Bingo', 'Bongo')
   end
 
   def env_for(url, opts = {})
@@ -190,7 +185,7 @@ def current_user
     end
 
     context "when Rack user doesn't contain any of the expect fields" do
-      let(:user_data) { described_class.new(OpenStruct.new).as_json }
+      let(:user_data) { described_class.new({}).as_json }
 
       it "is empty" do
         expect(user_data).to be_empty
diff --git a/spec/unit/rails/action_controller_notify_subscriber_spec.rb b/spec/unit/rails/action_controller_notify_subscriber_spec.rb
index 16b4509c0..a7d70708e 100644
--- a/spec/unit/rails/action_controller_notify_subscriber_spec.rb
+++ b/spec/unit/rails/action_controller_notify_subscriber_spec.rb
@@ -3,6 +3,8 @@
 require 'airbrake/rails/action_controller_notify_subscriber'
 
 RSpec.describe Airbrake::Rails::ActionControllerNotifySubscriber do
+  subject(:subscriber) { described_class.new }
+
   after { Airbrake::Rack::RequestStore.clear }
 
   describe "#call" do
@@ -10,12 +12,13 @@
 
     before do
       allow(Airbrake::Rails::Event).to receive(:new).and_return(event)
+      allow(Airbrake).to receive(:notify_request)
     end
 
     context "when there are no routes in the request store" do
       it "doesn't notify requests" do
-        expect(Airbrake).not_to receive(:notify_request)
-        subject.call([])
+        subscriber.call([])
+        expect(Airbrake).not_to have_received(:notify_request)
       end
     end
 
@@ -38,31 +41,39 @@
         end
 
         it "doesn't notify requests" do
-          expect(Airbrake).not_to receive(:notify_request)
-          subject.call([])
+          subscriber.call([])
+          expect(Airbrake).not_to have_received(:notify_request)
         end
       end
 
       context "and when the Airbrake config enables performance stats" do
+        let(:timestamp) { Time.now.to_f }
+
         before do
           allow(Airbrake::Config.instance)
             .to receive(:performance_stats).and_return(true)
+
+          allow(event).to receive(:method).and_return('GET')
+          allow(event).to receive(:status_code).and_return(200)
+          allow(event).to receive(:time).and_return(timestamp)
+          allow(event).to receive(:duration).and_return(1.234)
         end
 
         it "sends request info to Airbrake" do
-          expect(Airbrake).to receive(:notify_request).with(
+          subscriber.call([])
+
+          expect(Airbrake).to have_received(:notify_request).with(
             hash_including(
               method: 'GET',
               route: '/test-route',
               status_code: 200,
+              time: timestamp,
             ),
           )
-          expect(event).to receive(:method).and_return('GET')
-          expect(event).to receive(:status_code).and_return(200)
-          expect(event).to receive(:time).and_return(Time.now)
-          expect(event).to receive(:duration).and_return(1.234)
-
-          subject.call([])
+          expect(event).to have_received(:method)
+          expect(event).to have_received(:status_code)
+          expect(event).to have_received(:time)
+          expect(event).to have_received(:duration)
         end
       end
     end
diff --git a/spec/unit/rails/action_controller_performance_breakdown_subscriber_spec.rb b/spec/unit/rails/action_controller_performance_breakdown_subscriber_spec.rb
index fadfeef5d..7f9264857 100644
--- a/spec/unit/rails/action_controller_performance_breakdown_subscriber_spec.rb
+++ b/spec/unit/rails/action_controller_performance_breakdown_subscriber_spec.rb
@@ -95,7 +95,7 @@
         }
       end
 
-      it "sends request info as resource stash" do
+      it "sends request info as metric stash" do
         expect(Airbrake).to receive(:notify_performance_breakdown).with(
           an_instance_of(Hash),
           hash_including(request: request),
@@ -113,7 +113,7 @@
           )
         end
 
-        it "sends user info as resource stash" do
+        it "sends user info as metric stash" do
           expect(Airbrake).to receive(:notify_performance_breakdown).with(
             an_instance_of(Hash),
             hash_including(user: { 'id' => 1, 'name' => 'Arthur' }),
diff --git a/spec/unit/rails/action_controller_route_subscriber_spec.rb b/spec/unit/rails/action_controller_route_subscriber_spec.rb
index ec5432f79..d60b22ed6 100644
--- a/spec/unit/rails/action_controller_route_subscriber_spec.rb
+++ b/spec/unit/rails/action_controller_route_subscriber_spec.rb
@@ -1,6 +1,5 @@
 # frozen_string_literal: true
 
-require 'ostruct'
 require 'airbrake/rails/action_controller_route_subscriber'
 
 RSpec.describe Airbrake::Rails::ActionControllerRouteSubscriber do
diff --git a/spec/unit/rake/tasks_spec.rb b/spec/unit/rake/tasks_spec.rb
index 18251325d..813bacf0a 100644
--- a/spec/unit/rake/tasks_spec.rb
+++ b/spec/unit/rake/tasks_spec.rb
@@ -11,7 +11,7 @@ def wait_for_a_request_with_body(body)
 
   before do
     stub_request(:post, endpoint).to_return(status: 201, body: '{}')
-    allow(STDOUT).to receive(:puts).and_return(nil)
+    allow($stdout).to receive(:puts).and_return(nil)
   end
 
   describe "airbrake:deploy" do
@@ -62,7 +62,7 @@ def wait_for_a_request_with_body(body)
 
     describe "parsing environment variables" do
       it "does not raise when an env variable value contains '='" do
-        heroku_config = airbrake_vars + "URL=https://airbrake.io/docs?key=11\n"
+        heroku_config = "#{airbrake_vars} URL=https://airbrake.io/docs?key=11\n"
         expect(Bundler).to receive(:with_clean_env).twice.and_return(heroku_config)
 
         task.invoke
diff --git a/spec/unit/shoryuken_spec.rb b/spec/unit/shoryuken_spec.rb
index e7bcaeced..59bdb7b4b 100644
--- a/spec/unit/shoryuken_spec.rb
+++ b/spec/unit/shoryuken_spec.rb
@@ -89,7 +89,7 @@ def wait_for_a_request_with_body(body)
         timing: an_instance_of(Float),
       )
 
-      expect { subject.call(worker, queue, nil, body) {} }.not_to raise_error
+      expect { subject.call(worker, queue, nil, body) { 1 } }.not_to raise_error
     end
   end
 end