diff --git a/lib/bugsnag.rb b/lib/bugsnag.rb
index 950f1726..40a942e4 100644
--- a/lib/bugsnag.rb
+++ b/lib/bugsnag.rb
@@ -1,5 +1,10 @@
 require "rubygems"
 require "thread"
+require "set"
+require "json"
+require "uri"
+require "socket"
+require "logger"
 
 require "bugsnag/version"
 require "bugsnag/utility/feature_data_store"
@@ -21,21 +26,9 @@
 # as it doesn't auto-configure when loaded
 require "bugsnag/integrations/rack"
 
-require "bugsnag/middleware/rack_request"
-require "bugsnag/middleware/warden_user"
-require "bugsnag/middleware/clearance_user"
-require "bugsnag/middleware/callbacks"
-require "bugsnag/middleware/rails3_request"
-require "bugsnag/middleware/sidekiq"
-require "bugsnag/middleware/mailman"
-require "bugsnag/middleware/rake"
-require "bugsnag/middleware/classify_error"
-require "bugsnag/middleware/delayed_job"
-
 require "bugsnag/breadcrumb_type"
 require "bugsnag/breadcrumbs/validator"
 require "bugsnag/breadcrumbs/breadcrumb"
-require "bugsnag/breadcrumbs/breadcrumbs"
 
 require "bugsnag/utility/duplicator"
 require "bugsnag/utility/metadata_delegate"
diff --git a/lib/bugsnag/breadcrumbs/on_breadcrumb_callback_list.rb b/lib/bugsnag/breadcrumbs/on_breadcrumb_callback_list.rb
index df7cc5ad..bcf67fc4 100644
--- a/lib/bugsnag/breadcrumbs/on_breadcrumb_callback_list.rb
+++ b/lib/bugsnag/breadcrumbs/on_breadcrumb_callback_list.rb
@@ -1,5 +1,3 @@
-require "set"
-
 module Bugsnag::Breadcrumbs
   class OnBreadcrumbCallbackList
     def initialize(configuration)
diff --git a/lib/bugsnag/breadcrumbs/validator.rb b/lib/bugsnag/breadcrumbs/validator.rb
index 71ddbb16..a8b5bd3c 100644
--- a/lib/bugsnag/breadcrumbs/validator.rb
+++ b/lib/bugsnag/breadcrumbs/validator.rb
@@ -1,5 +1,3 @@
-require 'bugsnag/breadcrumbs/breadcrumbs'
-
 module Bugsnag::Breadcrumbs
   ##
   # Validates a given breadcrumb before it is stored
diff --git a/lib/bugsnag/cleaner.rb b/lib/bugsnag/cleaner.rb
index 33d0cd09..5bb08d34 100644
--- a/lib/bugsnag/cleaner.rb
+++ b/lib/bugsnag/cleaner.rb
@@ -1,5 +1,3 @@
-require 'uri'
-
 module Bugsnag
   # @api private
   class Cleaner
diff --git a/lib/bugsnag/configuration.rb b/lib/bugsnag/configuration.rb
index bcf64c81..0b4459af 100644
--- a/lib/bugsnag/configuration.rb
+++ b/lib/bugsnag/configuration.rb
@@ -1,20 +1,28 @@
-require "set"
-require "socket"
-require "logger"
-require "bugsnag/middleware_stack"
+require "bugsnag/breadcrumbs/on_breadcrumb_callback_list"
+
+require "bugsnag/endpoint_configuration"
+require "bugsnag/endpoint_validator"
+
+require "bugsnag/middleware/breadcrumbs"
 require "bugsnag/middleware/callbacks"
+require "bugsnag/middleware/classify_error"
+require "bugsnag/middleware/clearance_user"
+require "bugsnag/middleware/delayed_job"
 require "bugsnag/middleware/discard_error_class"
 require "bugsnag/middleware/exception_meta_data"
 require "bugsnag/middleware/ignore_error_class"
-require "bugsnag/middleware/suggestion_data"
-require "bugsnag/middleware/classify_error"
+require "bugsnag/middleware/mailman"
+require "bugsnag/middleware/rack_request"
+require "bugsnag/middleware/rails3_request"
+require "bugsnag/middleware/rake"
 require "bugsnag/middleware/session_data"
-require "bugsnag/middleware/breadcrumbs"
+require "bugsnag/middleware/sidekiq"
+require "bugsnag/middleware/suggestion_data"
+require "bugsnag/middleware/warden_user"
+
+require "bugsnag/middleware_stack"
+
 require "bugsnag/utility/circular_buffer"
-require "bugsnag/breadcrumbs/breadcrumbs"
-require "bugsnag/breadcrumbs/on_breadcrumb_callback_list"
-require "bugsnag/endpoint_configuration"
-require "bugsnag/endpoint_validator"
 
 module Bugsnag
   class Configuration
diff --git a/lib/bugsnag/delivery/synchronous.rb b/lib/bugsnag/delivery/synchronous.rb
index b0da7fde..5db31d87 100644
--- a/lib/bugsnag/delivery/synchronous.rb
+++ b/lib/bugsnag/delivery/synchronous.rb
@@ -1,5 +1,4 @@
 require "net/https"
-require "uri"
 
 module Bugsnag
   module Delivery
diff --git a/lib/bugsnag/delivery/thread_queue.rb b/lib/bugsnag/delivery/thread_queue.rb
index 2b82b221..3a5d5864 100644
--- a/lib/bugsnag/delivery/thread_queue.rb
+++ b/lib/bugsnag/delivery/thread_queue.rb
@@ -1,5 +1,3 @@
-require "thread"
-
 module Bugsnag
   module Delivery
     class ThreadQueue < Synchronous
diff --git a/lib/bugsnag/event.rb b/lib/bugsnag/event.rb
index af42bb81..b1770fc0 100644
--- a/lib/bugsnag/event.rb
+++ b/lib/bugsnag/event.rb
@@ -1,5 +1,3 @@
-require "bugsnag/report"
-
 module Bugsnag
   # For now Event is just an alias of Report. This points to the same object so
   # any changes to Report will also affect Event
diff --git a/lib/bugsnag/helpers.rb b/lib/bugsnag/helpers.rb
index 7a1c4178..1c030ac0 100644
--- a/lib/bugsnag/helpers.rb
+++ b/lib/bugsnag/helpers.rb
@@ -1,8 +1,3 @@
-require 'uri'
-require 'set'
-require 'json'
-
-
 module Bugsnag
   module Helpers # rubocop:todo Metrics/ModuleLength
     MAX_STRING_LENGTH = 3072
diff --git a/lib/bugsnag/integrations/mongo.rb b/lib/bugsnag/integrations/mongo.rb
index e1b2d22d..8f14de0f 100644
--- a/lib/bugsnag/integrations/mongo.rb
+++ b/lib/bugsnag/integrations/mongo.rb
@@ -1,5 +1,4 @@
 require 'mongo'
-require 'bugsnag/breadcrumbs/breadcrumbs'
 
 module Bugsnag
   ##
diff --git a/lib/bugsnag/integrations/rails/active_job.rb b/lib/bugsnag/integrations/rails/active_job.rb
index f262e63b..021f2ff8 100644
--- a/lib/bugsnag/integrations/rails/active_job.rb
+++ b/lib/bugsnag/integrations/rails/active_job.rb
@@ -1,5 +1,3 @@
-require 'set'
-
 module Bugsnag::Rails
   module ActiveJob
     SEVERITY = 'error'
diff --git a/lib/bugsnag/integrations/rails/rails_breadcrumbs.rb b/lib/bugsnag/integrations/rails/rails_breadcrumbs.rb
index 9659bce1..4c8aef9b 100644
--- a/lib/bugsnag/integrations/rails/rails_breadcrumbs.rb
+++ b/lib/bugsnag/integrations/rails/rails_breadcrumbs.rb
@@ -1,5 +1,3 @@
-require "bugsnag/breadcrumbs/breadcrumbs"
-
 module Bugsnag::Rails
   DEFAULT_RAILS_BREADCRUMBS = [
     {
diff --git a/lib/bugsnag/integrations/railtie.rb b/lib/bugsnag/integrations/railtie.rb
index d7613dd1..c875972a 100644
--- a/lib/bugsnag/integrations/railtie.rb
+++ b/lib/bugsnag/integrations/railtie.rb
@@ -1,10 +1,6 @@
 # Rails 3.x hooks
 
-require "json"
 require "rails"
-require "bugsnag"
-require "bugsnag/middleware/rails3_request"
-require "bugsnag/middleware/rack_request"
 require "bugsnag/integrations/rails/rails_breadcrumbs"
 
 module Bugsnag
diff --git a/lib/bugsnag/integrations/rake.rb b/lib/bugsnag/integrations/rake.rb
index 6d23668d..7ac173f8 100644
--- a/lib/bugsnag/integrations/rake.rb
+++ b/lib/bugsnag/integrations/rake.rb
@@ -1,4 +1,7 @@
-require 'bugsnag'
+# this file can either be required manually by a user, in which case 'bugsnag'
+# needs to be required, or it can be required automatically in the railtie,
+# in which case 'bugsnag' has already been required
+require 'bugsnag' unless defined?(Bugsnag)
 
 Rake::TaskManager.record_task_metadata = true
 
diff --git a/lib/bugsnag/middleware/rack_request.rb b/lib/bugsnag/middleware/rack_request.rb
index 387e5df4..94cb420b 100644
--- a/lib/bugsnag/middleware/rack_request.rb
+++ b/lib/bugsnag/middleware/rack_request.rb
@@ -1,5 +1,3 @@
-require "json"
-
 module Bugsnag::Middleware
   ##
   # Extracts and attaches rack data to an error report
diff --git a/lib/bugsnag/report.rb b/lib/bugsnag/report.rb
index 92d1b56c..91f8f4d6 100644
--- a/lib/bugsnag/report.rb
+++ b/lib/bugsnag/report.rb
@@ -1,4 +1,3 @@
-require "json"
 require "pathname"
 require "bugsnag/error"
 require "bugsnag/stacktrace"