diff --git a/config/application.rb b/config/application.rb
index 0fd053f83ffe43..7f7f8b5d6cc8be 100644
--- a/config/application.rb
+++ b/config/application.rb
@@ -71,15 +71,20 @@ class Application < Rails::Application
     # https://github.com/mastodon/mastodon/pull/24241#discussion_r1162890242
     config.active_support.cache_format_version = 6.1
 
-    config.add_autoload_paths_to_load_path = false
-
-    # 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)'
+    # Please, add to the `ignore` list any other `lib` subdirectories that do
+    # not contain `.rb` files, or that should not be reloaded or eager loaded.
+    # Common ones are `templates`, `generators`, or `middleware`, for example.
+    # config.autoload_lib(ignore: %w(assets tasks templates generators))
+    # TODO: We should enable this eventually, but for now there are many things
+    # in the wrong path from the perspective of zeitwerk.
+
+    # Configuration for the application, engines, and railties goes here.
+    #
+    # These settings can be overridden in specific environments using the files
+    # in config/environments, which are processed later.
+    #
+    # config.time_zone = "Central Time (US & Canada)"
+    # config.eager_load_paths << Rails.root.join("extras")
 
     # All translations from config/locales/*.rb,yml are auto loaded.
     # config.i18n.load_path += Dir[Rails.root.join('my', 'locales', '*.{rb,yml}').to_s]
diff --git a/config/environments/development.rb b/config/environments/development.rb
index 9a6637bdb9596d..e601fc014c4715 100644
--- a/config/environments/development.rb
+++ b/config/environments/development.rb
@@ -68,6 +68,9 @@
   # Highlight code that triggered database queries in logs.
   config.active_record.verbose_query_logs = true
 
+  # Highlight code that enqueued background job in logs.
+  config.active_job.verbose_enqueue_logs = true
+
   # Debug mode disables concatenation and preprocessing of assets.
   config.assets.debug = true
 
@@ -98,6 +101,9 @@
   # We provide a default secret for the development environment here.
   # This value should not be used in production environments!
   config.x.otp_secret = ENV.fetch('OTP_SECRET', '1fc2b87989afa6351912abeebe31ffc5c476ead9bf8b3d74cbc4a302c7b69a45b40b1bbef3506ddad73e942e15ed5ca4b402bf9a66423626051104f4b5f05109')
+
+  # Raise error when a before_action's only/except options reference missing actions
+  config.action_controller.raise_on_missing_callback_actions = true
 end
 
 Redis.raise_deprecations = true
diff --git a/config/environments/production.rb b/config/environments/production.rb
index 7da9d62410ab82..94e74699fc0355 100644
--- a/config/environments/production.rb
+++ b/config/environments/production.rb
@@ -6,7 +6,7 @@
   # Settings specified here will take precedence over those in config/application.rb.
 
   # Code is not reloaded between requests.
-  config.cache_classes = true
+  config.enable_reloading = false
 
   # Eager load code on boot. This eager loads most of Rails and
   # your application in memory, allowing both threaded web servers
@@ -19,8 +19,8 @@
   config.action_controller.perform_caching = true
   config.action_controller.asset_host      = ENV['CDN_HOST'] if ENV['CDN_HOST'].present?
 
-  # 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).
+  # Ensures that a master key has been made available in ENV["RAILS_MASTER_KEY"], config/master.key, or an environment
+  # key such as config/credentials/production.key. This key is used to decrypt credentials (and other encrypted files).
   # config.require_master_key = true
 
   # Compress CSS using a preprocessor.
@@ -48,10 +48,9 @@
     }
   }
 
-  # Include generic and useful information about system operation, but avoid logging too much
-  # information to avoid inadvertent exposure of personally identifiable information (PII).
-  # Use the lowest log level to ensure availability of diagnostic information
-  # when problems arise.
+  # Info include generic and useful information about system operation, but avoids logging too much
+  # information to avoid inadvertent exposure of personally identifiable information (PII). If you
+  # want to log everything, set the level to "debug".
   config.log_level = ENV.fetch('RAILS_LOG_LEVEL', 'info').to_sym
 
   # Prepend all log lines with the following tags.
@@ -72,10 +71,13 @@
 
   # Enable locale fallbacks for I18n (makes lookups for any locale fall back to
   # English when a translation cannot be found).
+  # This setting would typically be `true` to use the `I18n.default_locale`.
+  # Some locales are missing translation entries and would have errors:
+  # https://github.com/mastodon/mastodon/pull/24727
   config.i18n.fallbacks = [:en]
 
-  # Send deprecation notices to registered listeners.
-  config.active_support.deprecation = :notify
+  # Don't log any deprecations.
+  config.active_support.report_deprecations = false
 
   # Use default logging formatter so that PID and timestamp are not suppressed.
   config.log_formatter = ::Logger::Formatter.new
@@ -93,10 +95,10 @@
   # require "syslog/logger"
   # config.logger = ActiveSupport::TaggedLogging.new(Syslog::Logger.new "app-name")
 
-  ActiveSupport::Logger.new(STDOUT).tap do |logger|
-    logger.formatter = config.log_formatter
-    config.logger = ActiveSupport::TaggedLogging.new(logger)
-  end
+  # Log to STDOUT by default
+  config.logger = ActiveSupport::Logger.new(STDOUT)
+                                       .tap  { |logger| logger.formatter = ::Logger::Formatter.new }
+                                       .then { |logger| ActiveSupport::TaggedLogging.new(logger) }
 
   # Do not dump schema after migrations.
   config.active_record.dump_schema_after_migration = false
@@ -156,4 +158,12 @@
   }
 
   config.x.otp_secret = ENV.fetch('OTP_SECRET')
+
+  # Enable DNS rebinding protection and other `Host` header attacks.
+  # config.hosts = [
+  #   "example.com",     # Allow requests from example.com
+  #   /.*\.example\.com/ # Allow requests from subdomains like `www.example.com`
+  # ]
+  # Skip DNS rebinding protection for the default health check endpoint.
+  # config.host_authorization = { exclude: ->(request) { request.path == "/up" } }
 end
diff --git a/config/environments/test.rb b/config/environments/test.rb
index 210329848ed348..0b2f57fba7c339 100644
--- a/config/environments/test.rb
+++ b/config/environments/test.rb
@@ -10,12 +10,13 @@
 Rails.application.configure do
   # Settings specified here will take precedence over those in config/application.rb.
 
-  # Turn false under Spring and add config.action_view.cache_template_loading = true.
-  config.cache_classes = true
+  # While tests run files are not watched, reloading is not necessary.
+  config.enable_reloading = false
 
-  # Eager loading loads your whole application. When running a single test locally,
-  # this probably isn't necessary. It's a good idea to do in a continuous integration
-  # system, or in some way before deploying your code.
+  # Eager loading loads your entire application. When running a single test locally,
+  # this is usually not necessary, and can slow down your test suite. However, it's
+  # recommended that you enable it in continuous integration systems to ensure eager
+  # loading is working properly before deploying your code.
   config.eager_load = ENV['CI'].present?
 
   config.assets_digest = false
@@ -26,7 +27,7 @@
   config.cache_store = :memory_store
 
   # Raise exceptions instead of rendering exception templates.
-  config.action_dispatch.show_exceptions = false
+  config.action_dispatch.show_exceptions = :rescuable
 
   # Disable request forgery protection in test environment.
   config.action_controller.allow_forgery_protection = false
@@ -73,11 +74,14 @@
 
   # Annotate rendered view with file names.
   # config.action_view.annotate_rendered_view_with_filenames = true
+
+  # Raise error when a before_action's only/except options reference missing actions
+  config.action_controller.raise_on_missing_callback_actions = true
 end
 
 Paperclip::Attachment.default_options[:path] = Rails.root.join('spec', 'test_files', ':class', ':id_partition', ':style.:extension')
 
-# set fake_data for pam, don't do real calls, just use fake data
+# Enable fake_data for PAM
 if ENV['PAM_ENABLED'] == 'true'
   Rpam2.fake_data =
     {
diff --git a/config/initializers/content_security_policy.rb b/config/initializers/content_security_policy.rb
index 702341092165d4..e5e672f2c774c1 100644
--- a/config/initializers/content_security_policy.rb
+++ b/config/initializers/content_security_policy.rb
@@ -1,8 +1,10 @@
 # frozen_string_literal: true
 
-# Define an application-wide content security policy
-# For further information see the following documentation
-# https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Content-Security-Policy
+# Be sure to restart your server when you modify this file.
+
+# Define an application-wide content security policy.
+# See the Securing Rails Applications Guide for more information:
+# https://guides.rubyonrails.org/security.html#content-security-policy-header
 
 def host_to_url(str)
   return if str.blank?
diff --git a/config/initializers/cors.rb b/config/initializers/cors.rb
index 6424477846485c..37a818bf467bf9 100644
--- a/config/initializers/cors.rb
+++ b/config/initializers/cors.rb
@@ -3,7 +3,7 @@
 # Be sure to restart your server when you modify this file.
 
 # Avoid CORS issues when API is called from the frontend app.
-# Handle Cross-Origin Resource Sharing (CORS) in order to accept cross-origin AJAX requests.
+# Handle Cross-Origin Resource Sharing (CORS) in order to accept cross-origin Ajax requests.
 
 # Read more: https://github.com/cyu/rack-cors
 
diff --git a/config/initializers/filter_parameter_logging.rb b/config/initializers/filter_parameter_logging.rb
index ca55f952da0054..a119afa1244622 100644
--- a/config/initializers/filter_parameter_logging.rb
+++ b/config/initializers/filter_parameter_logging.rb
@@ -2,9 +2,9 @@
 
 # Be sure to restart your server when you modify this file.
 
-# Configure parameters to be filtered from the log file. Use this to limit dissemination of
-# sensitive information. See the ActiveSupport::ParameterFilter documentation for supported
-# notations and behaviors.
+# Configure parameters to be partially matched (e.g. passw matches password) and filtered from the log file.
+# Use this to limit dissemination of sensitive information.
+# See the ActiveSupport::ParameterFilter documentation for supported notations and behaviors.
 Rails.application.config.filter_parameters += [
   :passw, :secret, :token, :_key, :crypt, :salt, :certificate, :otp, :ssn
 ]
diff --git a/config/initializers/inflections.rb b/config/initializers/inflections.rb
index 0dad009b1fb97a..727a1350d00c36 100644
--- a/config/initializers/inflections.rb
+++ b/config/initializers/inflections.rb
@@ -6,9 +6,9 @@
 # are locale specific, and you may define rules for as many different
 # locales as you wish. All of these examples are active by default:
 # ActiveSupport::Inflector.inflections(:en) do |inflect|
-#   inflect.plural /^(ox)$/i, '\1en'
-#   inflect.singular /^(ox)en/i, '\1'
-#   inflect.irregular 'person', 'people'
+#   inflect.plural /^(ox)$/i, "\\1en"
+#   inflect.singular /^(ox)en/i, "\\1"
+#   inflect.irregular "person", "people"
 #   inflect.uncountable %w( fish sheep )
 # end
 
@@ -32,3 +32,8 @@
 
   inflect.singular 'data', 'data'
 end
+
+# These inflection rules are supported but not enabled by default:
+# ActiveSupport::Inflector.inflections(:en) do |inflect|
+#   inflect.acronym "RESTful"
+# end
diff --git a/config/initializers/new_framework_defaults_7_1.rb b/config/initializers/new_framework_defaults_7_1.rb
new file mode 100644
index 00000000000000..2fa0e42746ce22
--- /dev/null
+++ b/config/initializers/new_framework_defaults_7_1.rb
@@ -0,0 +1,225 @@
+# frozen_string_literal: true
+
+# Be sure to restart your server when you modify this file.
+#
+# This file eases your Rails 7.1 framework defaults upgrade.
+#
+# Uncomment each configuration one by one to switch to the new default.
+# Once your application is ready to run with all new defaults, you can remove
+# this file and set the `config.load_defaults` to `7.1`.
+#
+# Read the Guide for Upgrading Ruby on Rails for more info on each option.
+# https://guides.rubyonrails.org/upgrading_ruby_on_rails.html
+
+# No longer add autoloaded paths into `$LOAD_PATH`. This means that you won't be able
+# to manually require files that are managed by the autoloader, which you shouldn't do anyway.
+# This will reduce the size of the load path, making `require` faster if you don't use bootsnap, or reduce the size
+# of the bootsnap cache if you use it.
+Rails.application.config.add_autoload_paths_to_load_path = false
+
+# Remove the default X-Download-Options headers since it is used only by Internet Explorer.
+# If you need to support Internet Explorer, add back `"X-Download-Options" => "noopen"`.
+# Rails.application.config.action_dispatch.default_headers = {
+#   "X-Frame-Options" => "SAMEORIGIN",
+#   "X-XSS-Protection" => "0",
+#   "X-Content-Type-Options" => "nosniff",
+#   "X-Permitted-Cross-Domain-Policies" => "none",
+#   "Referrer-Policy" => "strict-origin-when-cross-origin"
+# }
+
+# Do not treat an `ActionController::Parameters` instance
+# as equal to an equivalent `Hash` by default.
+# Rails.application.config.action_controller.allow_deprecated_parameters_hash_equality = false
+
+# Active Record Encryption now uses SHA-256 as its hash digest algorithm. Important: If you have
+# data encrypted with previous Rails versions, there are two scenarios to consider:
+#
+# 1. If you have +config.active_support.key_generator_hash_digest_class+ configured as SHA1 (the default
+# before Rails 7.0), you need to configure SHA-1 for Active Record Encryption too:
+# Rails.application.config.active_record.encryption.hash_digest_class = OpenSSL::Digest::SHA1
+# 2. If you have +config.active_support.key_generator_hash_digest_class+ configured as SHA256 (the new default
+# in 7.0), then you need to configure SHA-256 for Active Record Encryption:
+# Rails.application.config.active_record.encryption.hash_digest_class = OpenSSL::Digest::SHA256
+#
+# If you don't currently have data encrypted with Active Record encryption, you can disable this setting to
+# configure the default behavior starting 7.1+:
+# Rails.application.config.active_record.encryption.support_sha1_for_non_deterministic_encryption = false
+
+# No longer run after_commit callbacks on the first of multiple Active Record
+# instances to save changes to the same database row within a transaction.
+# Instead, run these callbacks on the instance most likely to have internal
+# state which matches what was committed to the database, typically the last
+# instance to save.
+# Rails.application.config.active_record.run_commit_callbacks_on_first_saved_instances_in_transaction = false
+
+# Configures SQLite with a strict strings mode, which disables double-quoted string literals.
+#
+# SQLite has some quirks around double-quoted string literals.
+# It first tries to consider double-quoted strings as identifier names, but if they don't exist
+# it then considers them as string literals. Because of this, typos can silently go unnoticed.
+# For example, it is possible to create an index for a non existing column.
+# See https://www.sqlite.org/quirks.html#double_quoted_string_literals_are_accepted for more details.
+# Rails.application.config.active_record.sqlite3_adapter_strict_strings_by_default = true
+
+# Disable deprecated singular associations names
+# Rails.application.config.active_record.allow_deprecated_singular_associations_name = false
+
+# Enable the Active Job `BigDecimal` argument serializer, which guarantees
+# roundtripping. Without this serializer, some queue adapters may serialize
+# `BigDecimal` arguments as simple (non-roundtrippable) strings.
+#
+# When deploying an application with multiple replicas, old (pre-Rails 7.1)
+# replicas will not be able to deserialize `BigDecimal` arguments from this
+# serializer. Therefore, this setting should only be enabled after all replicas
+# have been successfully upgraded to Rails 7.1.
+# Rails.application.config.active_job.use_big_decimal_serializer = true
+
+# Specify if an `ArgumentError` should be raised if `Rails.cache` `fetch` or
+# `write` are given an invalid `expires_at` or `expires_in` time.
+# Options are `true`, and `false`. If `false`, the exception will be reported
+# as `handled` and logged instead.
+# Rails.application.config.active_support.raise_on_invalid_cache_expiration_time = true
+
+# Specify whether Query Logs will format tags using the SQLCommenter format
+# (https://open-telemetry.github.io/opentelemetry-sqlcommenter/), or using the legacy format.
+# Options are `:legacy` and `:sqlcommenter`.
+# Rails.application.config.active_record.query_log_tags_format = :sqlcommenter
+
+# Specify the default serializer used by `MessageEncryptor` and `MessageVerifier`
+# instances.
+#
+# The legacy default is `:marshal`, which is a potential vector for
+# deserialization attacks in cases where a message signing secret has been
+# leaked.
+#
+# In Rails 7.1, the new default is `:json_allow_marshal` which serializes and
+# deserializes with `ActiveSupport::JSON`, but can fall back to deserializing
+# with `Marshal` so that legacy messages can still be read.
+#
+# In Rails 7.2, the default will become `:json` which serializes and
+# deserializes with `ActiveSupport::JSON` only.
+#
+# Alternatively, you can choose `:message_pack` or `:message_pack_allow_marshal`,
+# which serialize with `ActiveSupport::MessagePack`. `ActiveSupport::MessagePack`
+# can roundtrip some Ruby types that are not supported by JSON, and may provide
+# improved performance, but it requires the `msgpack` gem.
+#
+# For more information, see
+# https://guides.rubyonrails.org/v7.1/configuring.html#config-active-support-message-serializer
+#
+# If you are performing a rolling deploy of a Rails 7.1 upgrade, wherein servers
+# that have not yet been upgraded must be able to read messages from upgraded
+# servers, first deploy without changing the serializer, then set the serializer
+# in a subsequent deploy.
+# Rails.application.config.active_support.message_serializer = :json_allow_marshal
+
+# Enable a performance optimization that serializes message data and metadata
+# together. This changes the message format, so messages serialized this way
+# cannot be read by older versions of Rails. However, messages that use the old
+# format can still be read, regardless of whether this optimization is enabled.
+#
+# To perform a rolling deploy of a Rails 7.1 upgrade, wherein servers that have
+# not yet been upgraded must be able to read messages from upgraded servers,
+# leave this optimization off on the first deploy, then enable it on a
+# subsequent deploy.
+# Rails.application.config.active_support.use_message_serializer_for_metadata = true
+
+# Set the maximum size for Rails log files.
+#
+# `config.load_defaults 7.1` does not set this value for environments other than
+# development and test.
+#
+# if Rails.env.local?
+#   Rails.application.config.log_file_size = 100 * 1024 * 1024
+# end
+
+# Enable raising on assignment to attr_readonly attributes. The previous
+# behavior would allow assignment but silently not persist changes to the
+# database.
+# Rails.application.config.active_record.raise_on_assign_to_attr_readonly = true
+
+# Enable validating only parent-related columns for presence when the parent is mandatory.
+# The previous behavior was to validate the presence of the parent record, which performed an extra query
+# to get the parent every time the child record was updated, even when parent has not changed.
+# Rails.application.config.active_record.belongs_to_required_validates_foreign_key = false
+
+# Enable precompilation of `config.filter_parameters`. Precompilation can
+# improve filtering performance, depending on the quantity and types of filters.
+# Rails.application.config.precompile_filter_parameters = true
+
+# Enable before_committed! callbacks on all enrolled records in a transaction.
+# The previous behavior was to only run the callbacks on the first copy of a record
+# if there were multiple copies of the same record enrolled in the transaction.
+# Rails.application.config.active_record.before_committed_on_all_records = true
+
+# Disable automatic column serialization into YAML.
+# To keep the historic behavior, you can set it to `YAML`, however it is
+# recommended to explicitly define the serialization method for each column
+# rather than to rely on a global default.
+# Rails.application.config.active_record.default_column_serializer = nil
+
+# Enable a performance optimization that serializes Active Record models
+# in a faster and more compact way.
+#
+# To perform a rolling deploy of a Rails 7.1 upgrade, wherein servers that have
+# not yet been upgraded must be able to read caches from upgraded servers,
+# leave this optimization off on the first deploy, then enable it on a
+# subsequent deploy.
+# Rails.application.config.active_record.marshalling_format_version = 7.1
+
+# Run `after_commit` and `after_*_commit` callbacks in the order they are defined in a model.
+# This matches the behaviour of all other callbacks.
+# In previous versions of Rails, they ran in the inverse order.
+# Rails.application.config.active_record.run_after_transaction_callbacks_in_order_defined = true
+
+# Whether a `transaction` block is committed or rolled back when exited via `return`, `break` or `throw`.
+#
+# Rails.application.config.active_record.commit_transaction_on_non_local_return = true
+
+# Controls when to generate a value for <tt>has_secure_token</tt> declarations.
+#
+# Rails.application.config.active_record.generate_secure_token_on = :initialize
+
+# ** Please read carefully, this must be configured in config/application.rb **
+# Change the format of the cache entry.
+# Changing this default means that all new cache entries added to the cache
+# will have a different format that is not supported by Rails 7.0
+# applications.
+# Only change this value after your application is fully deployed to Rails 7.1
+# and you have no plans to rollback.
+# When you're ready to change format, add this to `config/application.rb` (NOT
+# this file):
+#   config.active_support.cache_format_version = 7.1
+
+# Configure Action View to use HTML5 standards-compliant sanitizers when they are supported on your
+# platform.
+#
+# `Rails::HTML::Sanitizer.best_supported_vendor` will cause Action View to use HTML5-compliant
+# sanitizers if they are supported, else fall back to HTML4 sanitizers.
+#
+# In previous versions of Rails, Action View always used `Rails::HTML4::Sanitizer` as its vendor.
+#
+# Rails.application.config.action_view.sanitizer_vendor = Rails::HTML::Sanitizer.best_supported_vendor
+
+# Configure Action Text to use an HTML5 standards-compliant sanitizer when it is supported on your
+# platform.
+#
+# `Rails::HTML::Sanitizer.best_supported_vendor` will cause Action Text to use HTML5-compliant
+# sanitizers if they are supported, else fall back to HTML4 sanitizers.
+#
+# In previous versions of Rails, Action Text always used `Rails::HTML4::Sanitizer` as its vendor.
+#
+# Rails.application.config.action_text.sanitizer_vendor = Rails::HTML::Sanitizer.best_supported_vendor
+
+# Configure the log level used by the DebugExceptions middleware when logging
+# uncaught exceptions during requests
+# Rails.application.config.action_dispatch.debug_exception_log_level = :error
+
+# Configure the test helpers in Action View, Action Dispatch, and rails-dom-testing to use HTML5
+# parsers.
+#
+# Nokogiri::HTML5 isn't supported on JRuby, so JRuby applications must set this to :html4.
+#
+# In previous versions of Rails, these test helpers always used an HTML4 parser.
+#
+# Rails.application.config.dom_testing_default_html_version = :html5
diff --git a/config/initializers/permissions_policy.rb b/config/initializers/permissions_policy.rb
index 50bcf4eadec581..e8d0b2ae81179c 100644
--- a/config/initializers/permissions_policy.rb
+++ b/config/initializers/permissions_policy.rb
@@ -1,12 +1,15 @@
 # frozen_string_literal: true
+
+# Be sure to restart your server when you modify this file.
+
 # Define an application-wide HTTP permissions policy. For further
-# information see https://developers.google.com/web/updates/2018/06/feature-policy
-#
-# Rails.application.config.permissions_policy do |f|
-#   f.camera      :none
-#   f.gyroscope   :none
-#   f.microphone  :none
-#   f.usb         :none
-#   f.fullscreen  :self
-#   f.payment     :self, "https://secure.example.com"
+# information see: https://developers.google.com/web/updates/2018/06/feature-policy
+
+# Rails.application.config.permissions_policy do |policy|
+#   policy.camera      :none
+#   policy.gyroscope   :none
+#   policy.microphone  :none
+#   policy.usb         :none
+#   policy.fullscreen  :self
+#   policy.payment     :self, "https://secure.example.com"
 # end