diff --git a/.gitignore b/.gitignore
index 0a48702..921a949 100644
--- a/.gitignore
+++ b/.gitignore
@@ -22,6 +22,7 @@ doc
 # dummmy app
 test/dummy/log/*.log
 test/dummy/log/*.log*
+test/dummy/tmp
 
 rspec-persistence.txt
 
diff --git a/Gemfile.lock b/Gemfile.lock
index 44ac550..f729fb3 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -9,7 +9,7 @@ PATH
       valid (~> 1.0)
     diaspora_federation-json_schema (0.2.6)
     diaspora_federation-rails (0.2.6)
-      actionpack (>= 5, < 6)
+      actionpack (>= 5, < 7)
       diaspora_federation (= 0.2.6)
     diaspora_federation-test (0.2.6)
       diaspora_federation (= 0.2.6)
@@ -19,24 +19,25 @@ PATH
 GEM
   remote: https://rubygems.org/
   specs:
-    actionpack (5.2.3)
-      actionview (= 5.2.3)
-      activesupport (= 5.2.3)
+    actionpack (6.0.0)
+      actionview (= 6.0.0)
+      activesupport (= 6.0.0)
       rack (~> 2.0)
       rack-test (>= 0.6.3)
       rails-dom-testing (~> 2.0)
-      rails-html-sanitizer (~> 1.0, >= 1.0.2)
-    actionview (5.2.3)
-      activesupport (= 5.2.3)
+      rails-html-sanitizer (~> 1.0, >= 1.2.0)
+    actionview (6.0.0)
+      activesupport (= 6.0.0)
       builder (~> 3.1)
       erubi (~> 1.4)
       rails-dom-testing (~> 2.0)
-      rails-html-sanitizer (~> 1.0, >= 1.0.3)
-    activesupport (5.2.3)
+      rails-html-sanitizer (~> 1.1, >= 1.2.0)
+    activesupport (6.0.0)
       concurrent-ruby (~> 1.0, >= 1.0.2)
       i18n (>= 0.7, < 2)
       minitest (~> 5.1)
       tzinfo (~> 1.1)
+      zeitwerk (~> 2.1, >= 2.1.8)
     addressable (2.7.0)
       public_suffix (>= 2.0.2, < 5.0)
     ast (2.4.0)
@@ -150,12 +151,12 @@ GEM
       nokogiri (>= 1.6)
     rails-html-sanitizer (1.3.0)
       loofah (~> 2.3)
-    railties (5.2.3)
-      actionpack (= 5.2.3)
-      activesupport (= 5.2.3)
+    railties (6.0.0)
+      actionpack (= 6.0.0)
+      activesupport (= 6.0.0)
       method_source
       rake (>= 0.8.7)
-      thor (>= 0.19.0, < 2.0)
+      thor (>= 0.20.3, < 2.0)
     rainbow (3.0.0)
     rake (13.0.0)
     rb-fsevent (0.10.3)
@@ -233,6 +234,7 @@ GEM
       crack (>= 0.3.2)
       hashdiff (>= 0.4.0, < 2.0.0)
     yard (0.9.20)
+    zeitwerk (2.2.0)
 
 PLATFORMS
   ruby
diff --git a/config/spring.rb b/config/spring.rb
index 2bf4187..69680fe 100644
--- a/config/spring.rb
+++ b/config/spring.rb
@@ -5,4 +5,7 @@ Spring.application_root = "./test/dummy"
 root_path = Pathname.new(File.expand_path("."))
 Spring.watcher = Spring::Watcher::Listen.new(root_path, 0.2)
 
-Spring.watch("./lib/")
+Spring.watch(
+  "./lib/",
+  ".ruby-version"
+)
diff --git a/diaspora_federation-rails.gemspec b/diaspora_federation-rails.gemspec
index 7148c82..625372d 100644
--- a/diaspora_federation-rails.gemspec
+++ b/diaspora_federation-rails.gemspec
@@ -21,7 +21,7 @@ Gem::Specification.new do |s|
 
   s.required_ruby_version = "~> 2.5"
 
-  s.add_dependency "actionpack", ">= 5", "< 6"
+  s.add_dependency "actionpack", ">= 5", "< 7"
 
   s.add_dependency "diaspora_federation", DiasporaFederation::VERSION
 end
diff --git a/test/dummy/bin/rails b/test/dummy/bin/rails
index 5191e69..0739660 100755
--- a/test/dummy/bin/rails
+++ b/test/dummy/bin/rails
@@ -1,4 +1,4 @@
 #!/usr/bin/env ruby
-APP_PATH = File.expand_path('../../config/application', __FILE__)
+APP_PATH = File.expand_path('../config/application', __dir__)
 require_relative '../config/boot'
 require 'rails/commands'
diff --git a/test/dummy/config/application.rb b/test/dummy/config/application.rb
index 9ad1bef..dccc66d 100644
--- a/test/dummy/config/application.rb
+++ b/test/dummy/config/application.rb
@@ -2,29 +2,34 @@
 
 require_relative "boot"
 
+require "rails"
+# Pick the frameworks you want:
+# require "active_model/railtie"
+# require "active_job/railtie"
+# require "active_record/railtie"
+# require "active_storage/engine"
 require "action_controller/railtie"
+# require "action_mailer/railtie"
+# require "action_mailbox/engine"
+# require "action_text/engine"
+require "action_view/railtie"
+# require "action_cable/engine"
+# require "sprockets/railtie"
+require "rails/test_unit/railtie"
 
+# Require the gems listed in Gemfile, including any gems
+# you've limited to :test, :development, or :production.
 Bundler.require(*Rails.groups)
 require "diaspora_federation/rails"
 
 module Dummy
   class Application < Rails::Application
+    # Initialize configuration defaults for originally generated Rails version.
+    config.load_defaults 5.0
+
     # Settings in config/environments/* take precedence over those specified here.
-    # Application configuration should go into files in config/initializers
-    # -- all .rb files in that directory are automatically loaded.
-
-    # Set Time.zone default to the specified zone and make Active Record auto-convert to this zone.
-    # Run "rake -D time" for a list of tasks for finding time zone names. Default is UTC.
-    # config.time_zone = 'Central Time (US & Canada)'
-
-    # The default locale is :en and all translations from config/locales/*.rb,yml are auto loaded.
-    # config.i18n.load_path += Dir[Rails.root.join('my', 'locales', '*.{rb,yml}').to_s]
-    # config.i18n.default_locale = :de
-
-    # Version of your assets, change this if you want to expire all your assets
-    # config.assets.version = "1.0"
-
-    # autoload files from test/dummy/lib
-    config.autoload_once_paths += %W[#{config.root}/lib]
+    # Application configuration can go into files in config/initializers
+    # -- all .rb files in that directory are automatically loaded after loading
+    # the framework and any gems in your application.
   end
 end
diff --git a/test/dummy/config/environment.rb b/test/dummy/config/environment.rb
index 15b0f91..7df99e8 100644
--- a/test/dummy/config/environment.rb
+++ b/test/dummy/config/environment.rb
@@ -1,7 +1,7 @@
 # frozen_string_literal: true
 
-# Load the rails application
+# Load the Rails application.
 require_relative "application"
 
-# Initialize the rails application
+# Initialize the Rails application.
 Rails.application.initialize!
diff --git a/test/dummy/config/environments/development.rb b/test/dummy/config/environments/development.rb
index 1b163c3..d1a500a 100644
--- a/test/dummy/config/environments/development.rb
+++ b/test/dummy/config/environments/development.rb
@@ -11,36 +11,35 @@ Rails.application.configure do
   # Do not eager load code on boot.
   config.eager_load = false
 
-  # Show full error reports and disable caching.
-  config.consider_all_requests_local       = true
-  config.action_controller.perform_caching = false
+  # Show full error reports.
+  config.consider_all_requests_local = true
 
-  # Don't care if the mailer can't send.
-  # config.action_mailer.raise_delivery_errors = false
+  # Enable/disable caching. By default caching is disabled.
+  # Run rails dev:cache to toggle caching.
+  if Rails.root.join("tmp", "caching-dev.txt").exist?
+    config.action_controller.perform_caching = true
+    config.action_controller.enable_fragment_cache_logging = true
+
+    config.cache_store = :memory_store
+    config.public_file_server.headers = {
+      "Cache-Control" => "public, max-age=#{2.days.to_i}"
+    }
+  else
+    config.action_controller.perform_caching = false
+
+    config.cache_store = :null_store
+  end
 
   # Print deprecation notices to the Rails logger.
   config.active_support.deprecation = :log
 
-  # Raise an error on page load if there are pending migrations.
-  # config.active_record.migration_error = :page_load
-
-  # Debug mode disables concatenation and preprocessing of assets.
-  # This option may cause significant delays in view rendering with a large
-  # number of complex assets.
-  # config.assets.debug = true
-
-  # Asset digests allow you to set far-future HTTP expiration dates on all assets,
-  # yet still be able to expire them through the digest params.
-  # config.assets.digest = true
-
-  # Adds additional error checking when serving assets at runtime.
-  # Checks for improperly declared sprockets dependencies.
-  # Raises helpful error messages.
-  # config.assets.raise_runtime_errors = true
-
-  # Raises error for missing translations
+  # Raises error for missing translations.
   # config.action_view.raise_on_missing_translations = true
 
+  # Use an evented file watcher to asynchronously detect changes in source code,
+  # routes, locales, etc. This feature depends on the listen gem.
+  config.file_watcher = ActiveSupport::EventedFileUpdateChecker
+
   # Set the logging destination(s)
   config.log_to = %w[stdout file]
 
diff --git a/test/dummy/config/environments/production.rb b/test/dummy/config/environments/production.rb
index 65af5f6..f7d9dab 100644
--- a/test/dummy/config/environments/production.rb
+++ b/test/dummy/config/environments/production.rb
@@ -16,28 +16,16 @@ Rails.application.configure do
   config.consider_all_requests_local       = false
   config.action_controller.perform_caching = true
 
-  # Enable Rack::Cache to put a simple HTTP cache in front of your application
-  # Add `rack-cache` to your Gemfile before enabling this.
-  # For large-scale production use, consider using a caching reverse proxy like
-  # NGINX, varnish or squid.
-  # config.action_dispatch.rack_cache = true
+  # Ensures that a master key has been made available in either ENV["RAILS_MASTER_KEY"]
+  # or in config/master.key. This key is used to decrypt credentials (and other encrypted files).
+  # config.require_master_key = true
 
   # Disable serving static files from the `/public` folder by default since
   # Apache or NGINX already handles this.
-  config.serve_static_files = false
+  config.public_file_server.enabled = ENV["RAILS_SERVE_STATIC_FILES"].present?
 
-  # Compress JavaScripts and CSS.
-  # config.assets.js_compressor = :uglifier
-  # config.assets.css_compressor = :sass
-
-  # Do not fallback to assets pipeline if a precompiled asset is missed.
-  # config.assets.compile = false
-
-  # Asset digests allow you to set far-future HTTP expiration dates on all assets,
-  # yet still be able to expire them through the digest params.
-  # config.assets.digest = true
-
-  # `config.assets.precompile` and `config.assets.version` have moved to config/initializers/assets.rb
+  # Enable serving of images, stylesheets, and JavaScripts from an asset server.
+  # config.action_controller.asset_host = 'http://assets.example.com'
 
   # Specifies the header that your server uses for sending files.
   # config.action_dispatch.x_sendfile_header = 'X-Sendfile' # for Apache
@@ -57,20 +45,14 @@ Rails.application.configure do
   config.show_log_configuration = false
 
   # Prepend all log lines with the following tags.
-  # config.log_tags = [ :subdomain, :uuid ]
-
-  # Use a different logger for distributed setups.
-  # config.logger = ActiveSupport::TaggedLogging.new(SyslogLogger.new)
+  config.log_tags = [:request_id]
 
   # Use a different cache store in production.
   # config.cache_store = :mem_cache_store
 
-  # Enable serving of images, stylesheets, and JavaScripts from an asset server.
-  # config.action_controller.asset_host = 'http://assets.example.com'
-
-  # Ignore bad email addresses and do not raise email delivery errors.
-  # Set this to true and configure the email server for immediate delivery to raise delivery errors.
-  # config.action_mailer.raise_delivery_errors = false
+  # Use a real queuing backend for Active Job (and separate queues per environment).
+  # config.active_job.queue_adapter     = :resque
+  # config.active_job.queue_name_prefix = "dummy_production"
 
   # Enable locale fallbacks for I18n (makes lookups for any locale fall back to
   # the I18n.default_locale when a translation cannot be found).
@@ -82,6 +64,34 @@ Rails.application.configure do
   # Use default logging formatter so that PID and timestamp are not suppressed.
   config.log_formatter = ::Logger::Formatter.new
 
-  # Do not dump schema after migrations.
-  # config.active_record.dump_schema_after_migration = false
+  # Use a different logger for distributed setups.
+  # require 'syslog/logger'
+  # config.logger = ActiveSupport::TaggedLogging.new(Syslog::Logger.new 'app-name')
+
+  if ENV["RAILS_LOG_TO_STDOUT"].present?
+    logger           = ActiveSupport::Logger.new(STDOUT)
+    logger.formatter = config.log_formatter
+    config.logger    = ActiveSupport::TaggedLogging.new(logger)
+  end
+
+  # Inserts middleware to perform automatic connection switching.
+  # The `database_selector` hash is used to pass options to the DatabaseSelector
+  # middleware. The `delay` is used to determine how long to wait after a write
+  # to send a subsequent read to the primary.
+  #
+  # The `database_resolver` class is used by the middleware to determine which
+  # database is appropriate to use based on the time delay.
+  #
+  # The `database_resolver_context` class is used by the middleware to set
+  # timestamps for the last write to the primary. The resolver uses the context
+  # class timestamps to determine how long to wait before reading from the
+  # replica.
+  #
+  # By default Rails will store a last write timestamp in the session. The
+  # DatabaseSelector middleware is designed as such you can define your own
+  # strategy for connection switching and pass that into the middleware through
+  # these configuration options.
+  # config.active_record.database_selector = { delay: 2.seconds }
+  # config.active_record.database_resolver = ActiveRecord::Middleware::DatabaseSelector::Resolver
+  # config.active_record.database_resolver_context = ActiveRecord::Middleware::DatabaseSelector::Resolver::Session
 end
diff --git a/test/dummy/config/environments/test.rb b/test/dummy/config/environments/test.rb
index 711ecad..bae3b39 100644
--- a/test/dummy/config/environments/test.rb
+++ b/test/dummy/config/environments/test.rb
@@ -1,26 +1,30 @@
 # frozen_string_literal: true
 
+# The test environment is used exclusively to run your application's
+# test suite. You never need to work with it otherwise. Remember that
+# your test database is "scratch space" for the test suite and is wiped
+# and recreated between test runs. Don't rely on the data there!
+
 Rails.application.configure do
   # Settings specified here will take precedence over those in config/application.rb.
 
-  # The test environment is used exclusively to run your application's
-  # test suite. You never need to work with it otherwise. Remember that
-  # your test database is "scratch space" for the test suite and is wiped
-  # and recreated between test runs. Don't rely on the data there!
-  config.cache_classes = true
+  config.cache_classes = false
 
   # Do not eager load code on boot. This avoids loading your whole application
   # just for the purpose of running a single test. If you are using a tool that
   # preloads Rails for running tests, you may have to set it to true.
   config.eager_load = false
 
-  # Configure static file server for tests with Cache-Control for performance.
-  config.public_file_server.enable  = true
-  config.public_file_server.headers = {"Cache-Control" => "public, max-age=3600"}
+  # Configure public file server for tests with Cache-Control for performance.
+  config.public_file_server.enabled = true
+  config.public_file_server.headers = {
+    "Cache-Control" => "public, max-age=#{1.hour.to_i}"
+  }
 
   # Show full error reports and disable caching.
   config.consider_all_requests_local       = true
   config.action_controller.perform_caching = false
+  config.cache_store = :null_store
 
   # Raise exceptions instead of rendering exception templates.
   config.action_dispatch.show_exceptions = false
@@ -28,17 +32,9 @@ Rails.application.configure do
   # Disable request forgery protection in test environment.
   config.action_controller.allow_forgery_protection = false
 
-  # Tell Action Mailer not to deliver emails to the real world.
-  # The :test delivery method accumulates sent emails in the
-  # ActionMailer::Base.deliveries array.
-  # config.action_mailer.delivery_method = :test
-
-  # Randomize the order test cases are executed.
-  # config.active_support.test_order = :random
-
   # Print deprecation notices to the stderr.
-  # config.active_support.deprecation = :stderr
+  config.active_support.deprecation = :stderr
 
-  # Raises error for missing translations
+  # Raises error for missing translations.
   # config.action_view.raise_on_missing_translations = true
 end
diff --git a/test/dummy/config/initializers/cookies_serializer.rb b/test/dummy/config/initializers/cookies_serializer.rb
new file mode 100644
index 0000000..20a704a
--- /dev/null
+++ b/test/dummy/config/initializers/cookies_serializer.rb
@@ -0,0 +1,7 @@
+# frozen_string_literal: true
+
+# Be sure to restart your server when you modify this file.
+
+# Specify a serializer for the signed and encrypted cookie jars.
+# Valid options are :json, :marshal, and :hybrid.
+Rails.application.config.action_dispatch.cookies_serializer = :marshal
diff --git a/test/dummy/config/initializers/wrap_parameters.rb b/test/dummy/config/initializers/wrap_parameters.rb
index 4755468..e7148a3 100644
--- a/test/dummy/config/initializers/wrap_parameters.rb
+++ b/test/dummy/config/initializers/wrap_parameters.rb
@@ -7,10 +7,5 @@
 
 # Enable parameter wrapping for JSON. You can disable this by setting :format to an empty array.
 ActiveSupport.on_load(:action_controller) do
-  wrap_parameters format: [:json] if respond_to?(:wrap_parameters)
-end
-
-# To enable root element in JSON for ActiveRecord objects.
-ActiveSupport.on_load(:active_record) do
-  self.include_root_in_json = true
+  wrap_parameters format: [:json]
 end