diff --git a/.github/workflows/benchmark.yml b/.github/workflows/benchmark.yml
index 22f4458d5c5..a308765e71f 100644
--- a/.github/workflows/benchmark.yml
+++ b/.github/workflows/benchmark.yml
@@ -52,13 +52,16 @@ jobs:
 
       - name: Configure AWS credentials
         uses: aws-actions/configure-aws-credentials@v4
+        continue-on-error: true
         with:
           role-to-assume: arn:aws:iam::373952703873:role/BenchmarkReporter
           role-session-name: benchmark-reporter
           aws-region: us-east-1
 
       - name: Upload benchmark report
+        if: ${{ env.AWS_ACCESS_KEY_ID != '' }}
         run: bundle exec rake benchmark:upload-report
 
       - name: Put benchmark metrics
+        if: ${{ env.AWS_ACCESS_KEY_ID != '' }}
         run: bundle exec rake benchmark:put-metrics
diff --git a/build_tools/aws-sdk-code-generator/lib/aws-sdk-code-generator/helper.rb b/build_tools/aws-sdk-code-generator/lib/aws-sdk-code-generator/helper.rb
index ead8b228fb4..0e8f562610e 100644
--- a/build_tools/aws-sdk-code-generator/lib/aws-sdk-code-generator/helper.rb
+++ b/build_tools/aws-sdk-code-generator/lib/aws-sdk-code-generator/helper.rb
@@ -175,8 +175,18 @@ def wrap_string(str, width, indent = '')
       str.gsub(/(.{1,#{width}})(\s+|\Z)/, "#{indent}\\1\n").chomp
     end
 
+    def gem_lib_path(gem_name)
+      File.expand_path(
+        File.join(
+          __dir__,
+          "../../../../gems/#{gem_name}/lib/"
+        )
+      )
+    end
+
     module_function :deep_copy, :operation_streaming?, :downcase_first, :wrap_string, :apig_prefix,
-      :eventstream_output?, :eventstream_input?, :operation_eventstreaming?, :pascal_case
+      :eventstream_output?, :eventstream_input?, :operation_eventstreaming?, :pascal_case,
+      :gem_lib_path
 
   end
 end
diff --git a/build_tools/aws-sdk-code-generator/lib/aws-sdk-code-generator/views/errors_module.rb b/build_tools/aws-sdk-code-generator/lib/aws-sdk-code-generator/views/errors_module.rb
index 94360550a97..794d193d289 100644
--- a/build_tools/aws-sdk-code-generator/lib/aws-sdk-code-generator/views/errors_module.rb
+++ b/build_tools/aws-sdk-code-generator/lib/aws-sdk-code-generator/views/errors_module.rb
@@ -23,10 +23,31 @@ def generated_src_warning
         GENERATED_SRC_WARNING
       end
 
+      # @return [String]
       def module_name
         @service.module_name
       end
 
+      # @return [Boolean]
+      def customization_file_exists?
+        File.exist?(
+          File.join(
+            Helper.gem_lib_path(gem_name), "#{customization_file_path}.rb"
+          )
+        )
+      end
+
+      # @return [String]
+      def customization_file_path
+        "#{gem_name}/customizations/errors"
+      end
+
+      private
+
+      # @return [String]
+      def gem_name
+        "aws-sdk-#{module_name.split('::').last.downcase}"
+      end
     end
   end
 end
diff --git a/build_tools/aws-sdk-code-generator/lib/aws-sdk-code-generator/views/resource_class.rb b/build_tools/aws-sdk-code-generator/lib/aws-sdk-code-generator/views/resource_class.rb
index 09e2ee9465b..c4c05dcf044 100644
--- a/build_tools/aws-sdk-code-generator/lib/aws-sdk-code-generator/views/resource_class.rb
+++ b/build_tools/aws-sdk-code-generator/lib/aws-sdk-code-generator/views/resource_class.rb
@@ -106,8 +106,30 @@ def identifiers?
         @identifiers.size > 0
       end
 
+      # @return [Boolean]
+      def customization_file_exists?
+        File.exist?(
+          File.join(
+            Helper.gem_lib_path(gem_name), "#{resource_customization}.rb"
+          )
+        )
+      end
+
+      # @return [String]
+      def resource_customization
+        "#{gem_name}/customizations/#{underscored_name}"
+      end
+
       private
 
+      def gem_name
+        "aws-sdk-#{module_name.split('::').last.downcase}"
+      end
+
+      def underscored_name
+        class_name.gsub(/([a-z])([A-Z])/, '\1_\2').downcase
+      end
+
       def build_associations(options)
         ResourceAssociation.build_list(
           class_name: options.fetch(:class_name),
diff --git a/build_tools/aws-sdk-code-generator/lib/aws-sdk-code-generator/views/root_resource_class.rb b/build_tools/aws-sdk-code-generator/lib/aws-sdk-code-generator/views/root_resource_class.rb
index 9540769d608..5eed979787c 100644
--- a/build_tools/aws-sdk-code-generator/lib/aws-sdk-code-generator/views/root_resource_class.rb
+++ b/build_tools/aws-sdk-code-generator/lib/aws-sdk-code-generator/views/root_resource_class.rb
@@ -53,6 +53,25 @@ def documentation?
         actions? || associations?
       end
 
+      # @return [Boolean]
+      def customization_file_exists?
+        File.exist?(
+          File.join(
+            Helper.gem_lib_path(gem_name), "#{customization_file_path}.rb"
+          )
+        )
+      end
+
+      # @return [String]
+      def customization_file_path
+        "#{gem_name}/customizations/resource"
+      end
+
+      private
+
+      def gem_name
+        "aws-sdk-#{module_name.split('::').last.downcase}"
+      end
     end
   end
 end
diff --git a/build_tools/aws-sdk-code-generator/lib/aws-sdk-code-generator/views/service_module.rb b/build_tools/aws-sdk-code-generator/lib/aws-sdk-code-generator/views/service_module.rb
index b78f133c7a3..733d6a8fdc5 100644
--- a/build_tools/aws-sdk-code-generator/lib/aws-sdk-code-generator/views/service_module.rb
+++ b/build_tools/aws-sdk-code-generator/lib/aws-sdk-code-generator/views/service_module.rb
@@ -11,7 +11,7 @@ class ServiceModule < View
       def initialize(options)
         @service = options.fetch(:service)
         @prefix = options.fetch(:prefix)
-        @codegenerated_plugins = options.fetch(:codegenerated_plugins)
+        @codegenerated_plugins = options.fetch(:codegenerated_plugins) || []
       end
 
       # @return [String|nil]
@@ -60,47 +60,56 @@ def require_core_guard?
         @service.included_in_core?
       end
 
-      # @return [Array<String>]
-      def relative_requires
-        paths = Set.new
-        paths << "#{@prefix}/types"
-        paths << "#{@prefix}/client_api"
+      # @return [Array<Hash>] list of autoload path hashes with :path, :class_name and
+      # :is_plugin keys.
+      def autoloads
+        paths = []
+        paths << auto_load("#{@prefix}/types", :Types)
+        paths << auto_load("#{@prefix}/client_api", :ClientApi)
 
         # these must be required before the client
-        if @codegenerated_plugins
-          paths += @codegenerated_plugins.map { | p| p.path }
+        paths += @codegenerated_plugins.map do |p|
+          auto_load(p.path, p.class_name.split('::').last, true)
         end
 
-        paths << "#{@prefix}/client"
-        paths << "#{@prefix}/errors"
-        paths << "#{@prefix}/waiters" if @service.waiters
-        paths << "#{@prefix}/resource"
+        paths << auto_load("#{@prefix}/client", :Client)
+        paths << auto_load("#{@prefix}/errors", :Errors)
+        paths << auto_load("#{@prefix}/waiters", :Waiters) if @service.waiters
+        paths << auto_load("#{@prefix}/resource", :Resource)
 
         unless @service.legacy_endpoints?
-          paths << "#{@prefix}/endpoint_parameters"
-          paths << "#{@prefix}/endpoint_provider"
-          paths << "#{@prefix}/endpoints"
+          paths << auto_load("#{@prefix}/endpoint_parameters", :EndpointParameters)
+          paths << auto_load("#{@prefix}/endpoint_provider", :EndpointProvider)
+          paths << auto_load("#{@prefix}/endpoints", :Endpoints)
         end
 
         if @service.resources && @service.resources['resources']
           @service.resources['resources'].keys.each do |resource_name|
             path = "#{@prefix}/#{underscore(resource_name)}"
-            if paths.include?(path)
-              raise "resource path conflict for `#{resource_name}'"
-            else
-              paths << path
-            end
+            paths << auto_load(path, resource_name)
           end
         end
-        paths << "#{@prefix}/customizations"
         if @service.api['metadata']['protocolSettings'] &&
-          @service.api['metadata']['protocolSettings']['h2'] == 'eventstream'
-          paths << "#{@prefix}/async_client"
-          paths << "#{@prefix}/event_streams"
+           @service.api['metadata']['protocolSettings']['h2'] == 'eventstream'
+          paths << auto_load("#{@prefix}/async_client", :AsyncClient)
+          paths << auto_load("#{@prefix}/event_streams", :EventStreams)
         elsif eventstream_shape?
-          paths << "#{@prefix}/event_streams"
+          paths << auto_load("#{@prefix}/event_streams", :EventStreams)
         end
-        paths.to_a
+
+        paths
+      end
+
+      def auto_load(path, class_name, is_plugin = false)
+        {
+          file_path: path,
+          class_name: class_name,
+          is_plugin: is_plugin
+        }
+      end
+
+      def service_identifier
+        @prefix
       end
 
       def example_var_name
@@ -108,7 +117,8 @@ def example_var_name
       end
 
       def example_operation_name
-        raise "no operations found for the service" if @service.api['operations'].empty?
+        raise 'no operations found for the service' if @service.api['operations'].empty?
+
         underscore(@service.api['operations'].keys.first)
       end
 
diff --git a/build_tools/aws-sdk-code-generator/lib/aws-sdk-code-generator/views/types_module.rb b/build_tools/aws-sdk-code-generator/lib/aws-sdk-code-generator/views/types_module.rb
index 492c9e76faa..134294d663f 100644
--- a/build_tools/aws-sdk-code-generator/lib/aws-sdk-code-generator/views/types_module.rb
+++ b/build_tools/aws-sdk-code-generator/lib/aws-sdk-code-generator/views/types_module.rb
@@ -80,8 +80,20 @@ def eventstreams
         end
       end
 
+      # @return [Array<String>]
+      def types_customizations
+        Dir.glob(File.join(Helper.gem_lib_path(gem_name), "#{gem_name}/customizations/types", '*.rb')).map do |file|
+          filename = File.basename(file, '.rb')
+          "#{gem_name}/customizations/types/#{filename}"
+        end
+      end
+
       private
 
+      def gem_name
+        "aws-sdk-#{module_name.split('::').last.downcase}"
+      end
+
       def struct_members(shape)
         return if shape['members'].nil?
         members = shape['members'].map do |member_name, member_ref|
diff --git a/build_tools/aws-sdk-code-generator/templates/client_api_module.mustache b/build_tools/aws-sdk-code-generator/templates/client_api_module.mustache
index c2d3b37d280..a8f79f38df5 100644
--- a/build_tools/aws-sdk-code-generator/templates/client_api_module.mustache
+++ b/build_tools/aws-sdk-code-generator/templates/client_api_module.mustache
@@ -3,6 +3,7 @@
 {{#generated_src_warning}}
 {{generated_src_warning}}
 {{/generated_src_warning}}
+
 module {{module_name}}
   # @api private
   module ClientApi
diff --git a/build_tools/aws-sdk-code-generator/templates/errors_module.mustache b/build_tools/aws-sdk-code-generator/templates/errors_module.mustache
index f73c0484d8c..74ea2c830b5 100644
--- a/build_tools/aws-sdk-code-generator/templates/errors_module.mustache
+++ b/build_tools/aws-sdk-code-generator/templates/errors_module.mustache
@@ -68,3 +68,8 @@ module {{module_name}}
     {{/errors}}
   end
 end
+{{#customization_file_exists?}}
+
+# Load customizations if they exist
+require '{{customization_file_path}}'
+{{/customization_file_exists?}}
diff --git a/build_tools/aws-sdk-code-generator/templates/resource_class.mustache b/build_tools/aws-sdk-code-generator/templates/resource_class.mustache
index 9a4e40074e8..a0809c86a6f 100644
--- a/build_tools/aws-sdk-code-generator/templates/resource_class.mustache
+++ b/build_tools/aws-sdk-code-generator/templates/resource_class.mustache
@@ -304,3 +304,8 @@ module {{module_name}}
     {{/batch_actions?}}
   end
 end
+{{#customization_file_exists?}}
+
+# Load customizations if they exist
+require '{{resource_customization}}'
+{{/customization_file_exists?}}
diff --git a/build_tools/aws-sdk-code-generator/templates/root_resource_class.mustache b/build_tools/aws-sdk-code-generator/templates/root_resource_class.mustache
index 6c5e437435e..2e81a762f41 100644
--- a/build_tools/aws-sdk-code-generator/templates/root_resource_class.mustache
+++ b/build_tools/aws-sdk-code-generator/templates/root_resource_class.mustache
@@ -49,3 +49,8 @@ module {{module_name}}
 
   end
 end
+{{#customization_file_exists?}}
+
+# Load customizations if they exist
+require '{{customization_file_path}}'
+{{/customization_file_exists?}}
diff --git a/build_tools/aws-sdk-code-generator/templates/service_module.mustache b/build_tools/aws-sdk-code-generator/templates/service_module.mustache
index da90252cc0e..4f543324d88 100644
--- a/build_tools/aws-sdk-code-generator/templates/service_module.mustache
+++ b/build_tools/aws-sdk-code-generator/templates/service_module.mustache
@@ -17,10 +17,6 @@ require '{{.}}'
 {{/requires}}
 {{/require_core_guard?}}
 
-{{#relative_requires}}
-require_relative '{{.}}'
-{{/relative_requires}}
-
 # This module provides support for {{full_name}}. This module is available in the
 # `{{gem_name}}` gem.
 #
@@ -52,7 +48,19 @@ require_relative '{{.}}'
 #
 # @!group service
 module {{module_name}}
+  {{#autoloads}}
+    {{#is_plugin}}
+  module Plugins
+    autoload :{{class_name}}, '{{file_path}}'
+  end
+    {{/is_plugin}}
+    {{^is_plugin}}
+  autoload :{{class_name}}, '{{file_path}}'
+    {{/is_plugin}}
+  {{/autoloads}}
 
   GEM_VERSION = '{{gem_version}}'
 
 end
+
+require_relative '{{service_identifier}}/customizations'
diff --git a/build_tools/aws-sdk-code-generator/templates/types_module.mustache b/build_tools/aws-sdk-code-generator/templates/types_module.mustache
index 0fab503b64a..12a6fae9133 100644
--- a/build_tools/aws-sdk-code-generator/templates/types_module.mustache
+++ b/build_tools/aws-sdk-code-generator/templates/types_module.mustache
@@ -51,3 +51,7 @@ module {{module_name}}
 
   end
 end
+
+{{#types_customizations}}
+require "{{.}}"
+{{/types_customizations}}
diff --git a/gems/aws-sdk-cloudfront/lib/aws-sdk-cloudfront/customizations.rb b/gems/aws-sdk-cloudfront/lib/aws-sdk-cloudfront/customizations.rb
index 94f58989d45..c68664bdf7a 100644
--- a/gems/aws-sdk-cloudfront/lib/aws-sdk-cloudfront/customizations.rb
+++ b/gems/aws-sdk-cloudfront/lib/aws-sdk-cloudfront/customizations.rb
@@ -1,6 +1,10 @@
 # frozen_string_literal: true
 
 # utility classes
-require 'aws-sdk-cloudfront/signer'
-require 'aws-sdk-cloudfront/url_signer'
-require 'aws-sdk-cloudfront/cookie_signer'
+module Aws
+  module CloudFront
+    autoload :Signer, 'aws-sdk-cloudfront/signer'
+    autoload :UrlSigner, 'aws-sdk-cloudfront/url_signer'
+    autoload :CookieSigner, 'aws-sdk-cloudfront/cookie_signer'
+  end
+end
diff --git a/gems/aws-sdk-cognitoidentity/lib/aws-sdk-cognitoidentity/customizations.rb b/gems/aws-sdk-cognitoidentity/lib/aws-sdk-cognitoidentity/customizations.rb
index 08d6646c96e..c2820259bec 100644
--- a/gems/aws-sdk-cognitoidentity/lib/aws-sdk-cognitoidentity/customizations.rb
+++ b/gems/aws-sdk-cognitoidentity/lib/aws-sdk-cognitoidentity/customizations.rb
@@ -1,3 +1,7 @@
 # frozen_string_literal: true
 
-require 'aws-sdk-cognitoidentity/customizations/cognito_identity_credentials'
\ No newline at end of file
+module Aws
+  module CognitoIdentity
+    autoload :CognitoIdentityCredentials, 'aws-sdk-cognitoidentity/customizations/cognito_identity_credentials'
+  end
+end
diff --git a/gems/aws-sdk-core/CHANGELOG.md b/gems/aws-sdk-core/CHANGELOG.md
index df4938ad3f0..944afdc0b4d 100644
--- a/gems/aws-sdk-core/CHANGELOG.md
+++ b/gems/aws-sdk-core/CHANGELOG.md
@@ -1,6 +1,8 @@
 Unreleased Changes
 ------------------
 
+* Feature - Use autoloading at the service level to load service clients and resources.
+
 3.207.0 (2024-09-20)
 ------------------
 
diff --git a/gems/aws-sdk-core/lib/aws-defaults.rb b/gems/aws-sdk-core/lib/aws-defaults.rb
index 94050821ba1..0961c86fa69 100644
--- a/gems/aws-sdk-core/lib/aws-defaults.rb
+++ b/gems/aws-sdk-core/lib/aws-defaults.rb
@@ -1,3 +1,6 @@
 # frozen_string_literal: true
 
-require_relative 'aws-defaults/default_configuration'
\ No newline at end of file
+module Aws
+  autoload :DefaultsModeConfiguration, 'aws-defaults/default_configuration'
+  autoload :DefaultsModeConfigResolver, 'aws-defaults/defaults_mode_config_resolver'
+end
diff --git a/gems/aws-sdk-core/lib/aws-sdk-core.rb b/gems/aws-sdk-core/lib/aws-sdk-core.rb
index c1c6a45a278..e03196d5fec 100644
--- a/gems/aws-sdk-core/lib/aws-sdk-core.rb
+++ b/gems/aws-sdk-core/lib/aws-sdk-core.rb
@@ -5,113 +5,77 @@
 require 'jmespath'
 
 require_relative 'aws-sdk-core/deprecations'
-
-# credential providers
-require_relative 'aws-sdk-core/credential_provider'
-require_relative 'aws-sdk-core/refreshing_credentials'
-require_relative 'aws-sdk-core/assume_role_credentials'
-require_relative 'aws-sdk-core/assume_role_web_identity_credentials'
-require_relative 'aws-sdk-core/credentials'
-require_relative 'aws-sdk-core/credential_provider_chain'
-require_relative 'aws-sdk-core/ecs_credentials'
-require_relative 'aws-sdk-core/instance_profile_credentials'
-require_relative 'aws-sdk-core/shared_credentials'
-require_relative 'aws-sdk-core/process_credentials'
-require_relative 'aws-sdk-core/sso_credentials'
-
-# tokens and token providers
-require_relative 'aws-sdk-core/token'
-require_relative 'aws-sdk-core/token_provider'
-require_relative 'aws-sdk-core/static_token_provider'
-require_relative 'aws-sdk-core/refreshing_token'
-require_relative 'aws-sdk-core/sso_token_provider'
-require_relative 'aws-sdk-core/token_provider_chain'
-require_relative 'aws-sdk-core/plugins/bearer_authorization'
-
-# client modules
-require_relative 'aws-sdk-core/client_stubs'
-require_relative 'aws-sdk-core/async_client_stubs'
-require_relative 'aws-sdk-core/eager_loader'
-require_relative 'aws-sdk-core/errors'
-require_relative 'aws-sdk-core/pageable_response'
-require_relative 'aws-sdk-core/pager'
-require_relative 'aws-sdk-core/param_converter'
-require_relative 'aws-sdk-core/param_validator'
-require_relative 'aws-sdk-core/shared_config'
-require_relative 'aws-sdk-core/structure'
-require_relative 'aws-sdk-core/type_builder'
-require_relative 'aws-sdk-core/util'
-
-# resource classes
-require_relative 'aws-sdk-core/resources/collection'
-
-# logging
-require_relative 'aws-sdk-core/log/formatter'
-require_relative 'aws-sdk-core/log/param_filter'
-require_relative 'aws-sdk-core/log/param_formatter'
-
-# stubbing
-require_relative 'aws-sdk-core/stubbing/empty_stub'
-require_relative 'aws-sdk-core/stubbing/data_applicator'
-require_relative 'aws-sdk-core/stubbing/stub_data'
-require_relative 'aws-sdk-core/stubbing/xml_error'
-
-# stubbing protocols
-require_relative 'aws-sdk-core/stubbing/protocols/json'
-require_relative 'aws-sdk-core/stubbing/protocols/rest'
-require_relative 'aws-sdk-core/stubbing/protocols/rest_json'
-require_relative 'aws-sdk-core/stubbing/protocols/rest_xml'
-require_relative 'aws-sdk-core/stubbing/protocols/query'
-require_relative 'aws-sdk-core/stubbing/protocols/ec2'
-require_relative 'aws-sdk-core/stubbing/protocols/rpc_v2'
-require_relative 'aws-sdk-core/stubbing/protocols/api_gateway'
-
-# protocols
-require_relative 'aws-sdk-core/error_handler'
-require_relative 'aws-sdk-core/rest'
-require_relative 'aws-sdk-core/xml'
-require_relative 'aws-sdk-core/json'
-require_relative 'aws-sdk-core/query'
-require_relative 'aws-sdk-core/rpc_v2'
-
-# event stream
-require_relative 'aws-sdk-core/binary'
-require_relative 'aws-sdk-core/event_emitter'
-
-# endpoint discovery
-require_relative 'aws-sdk-core/endpoint_cache'
-
-# client metrics / telemetry
-require_relative 'aws-sdk-core/client_side_monitoring/request_metrics'
-require_relative 'aws-sdk-core/client_side_monitoring/publisher'
-require_relative 'aws-sdk-core/telemetry'
-
-# utilities
-require_relative 'aws-sdk-core/arn'
-require_relative 'aws-sdk-core/arn_parser'
-require_relative 'aws-sdk-core/ec2_metadata'
-require_relative 'aws-sdk-core/lru_cache'
-
-# dynamic endpoints
-require_relative 'aws-sdk-core/endpoints'
-require_relative 'aws-sdk-core/plugins/signature_v4'
-
 # defaults
 require_relative 'aws-defaults'
 
-# plugins
-# loaded through building STS or SSO ..
-
-# aws-sdk-sts is included to support Aws::AssumeRoleCredentials
-require_relative 'aws-sdk-sts'
-
-# aws-sdk-sso is included to support Aws::SSOCredentials
-require_relative 'aws-sdk-sso'
-require_relative 'aws-sdk-ssooidc'
-
 module Aws
 
-  CORE_GEM_VERSION = File.read(File.expand_path('../../VERSION', __FILE__)).strip
+  autoload :IniParser, 'aws-sdk-core/ini_parser'
+
+  # Credentials and credentials providers
+  autoload :Credentials, 'aws-sdk-core/credentials'
+  autoload :CredentialProvider, 'aws-sdk-core/credential_provider'
+  autoload :RefreshingCredentials, 'aws-sdk-core/refreshing_credentials'
+  autoload :AssumeRoleCredentials, 'aws-sdk-core/assume_role_credentials'
+  autoload :AssumeRoleWebIdentityCredentials, 'aws-sdk-core/assume_role_web_identity_credentials'
+  autoload :CredentialProviderChain, 'aws-sdk-core/credential_provider_chain'
+  autoload :ECSCredentials, 'aws-sdk-core/ecs_credentials'
+  autoload :InstanceProfileCredentials, 'aws-sdk-core/instance_profile_credentials'
+  autoload :SharedCredentials, 'aws-sdk-core/shared_credentials'
+  autoload :ProcessCredentials, 'aws-sdk-core/process_credentials'
+  autoload :SSOCredentials, 'aws-sdk-core/sso_credentials'
+
+
+  # tokens and token providers
+  autoload :Token, 'aws-sdk-core/token'
+  autoload :TokenProvider, 'aws-sdk-core/token_provider'
+  autoload :StaticTokenProvider, 'aws-sdk-core/static_token_provider'
+  autoload :RefreshingToken, 'aws-sdk-core/refreshing_token'
+  autoload :SSOTokenProvider, 'aws-sdk-core/sso_token_provider'
+  autoload :TokenProviderChain, 'aws-sdk-core/token_provider_chain'
+
+  # client modules
+  autoload :ClientStubs, 'aws-sdk-core/client_stubs'
+  autoload :AsyncClientStubs, 'aws-sdk-core/async_client_stubs'
+  autoload :EagerLoader, 'aws-sdk-core/eager_loader'
+  autoload :Errors, 'aws-sdk-core/errors'
+  autoload :PageableResponse, 'aws-sdk-core/pageable_response'
+  autoload :Pager, 'aws-sdk-core/pager'
+  autoload :ParamConverter, 'aws-sdk-core/param_converter'
+  autoload :ParamValidator, 'aws-sdk-core/param_validator'
+  autoload :SharedConfig, 'aws-sdk-core/shared_config'
+  autoload :Structure, 'aws-sdk-core/structure'
+  autoload :EmptyStructure, 'aws-sdk-core/structure'
+  autoload :TypeBuilder, 'aws-sdk-core/type_builder'
+  autoload :Util, 'aws-sdk-core/util'
+
+  # protocols
+  autoload :ErrorHandler, 'aws-sdk-core/error_handler'
+  autoload :Rest, 'aws-sdk-core/rest'
+  autoload :Xml, 'aws-sdk-core/xml'
+  autoload :Json, 'aws-sdk-core/json'
+  autoload :Query, 'aws-sdk-core/query'
+  autoload :RpcV2, 'aws-sdk-core/rpc_v2'
+
+  # event stream
+  autoload :Binary, 'aws-sdk-core/binary'
+  autoload :EventEmitter, 'aws-sdk-core/event_emitter'
+
+  # endpoint discovery
+  autoload :EndpointCache, 'aws-sdk-core/endpoint_cache'
+
+  autoload :Telemetry, 'aws-sdk-core/telemetry'
+
+  # utilities
+  autoload :ARN, 'aws-sdk-core/arn'
+  autoload :ARNParser, 'aws-sdk-core/arn_parser'
+  autoload :EC2Metadata, 'aws-sdk-core/ec2_metadata'
+  autoload :LRUCache, 'aws-sdk-core/lru_cache'
+
+  # dynamic endpoints
+  autoload :Endpoints, 'aws-sdk-core/endpoints'
+
+  CORE_GEM_VERSION = File.read(File.expand_path('../VERSION', __dir__)).strip
 
   @config = {}
 
@@ -195,3 +159,18 @@ def eager_autoload!(*args)
 
   end
 end
+
+# Setup additional autoloads/modules
+require_relative 'aws-sdk-core/client_side_monitoring'
+require_relative 'aws-sdk-core/log'
+require_relative 'aws-sdk-core/plugins'
+require_relative 'aws-sdk-core/resources'
+require_relative 'aws-sdk-core/stubbing'
+require_relative 'aws-sdk-core/waiters'
+
+# aws-sdk-sts is included to support Aws::AssumeRoleCredentials
+require_relative 'aws-sdk-sts'
+
+# aws-sdk-sso is included to support Aws::SSOCredentials
+require_relative 'aws-sdk-sso'
+require_relative 'aws-sdk-ssooidc'
diff --git a/gems/aws-sdk-core/lib/aws-sdk-core/client_side_monitoring.rb b/gems/aws-sdk-core/lib/aws-sdk-core/client_side_monitoring.rb
new file mode 100644
index 00000000000..3079edb2cd6
--- /dev/null
+++ b/gems/aws-sdk-core/lib/aws-sdk-core/client_side_monitoring.rb
@@ -0,0 +1,9 @@
+# frozen_string_literal: true
+
+module Aws
+  # setup autoloading for ClientSideMonitoring module
+  module ClientSideMonitoring
+    autoload :RequestMetrics, 'aws-sdk-core/client_side_monitoring/request_metrics'
+    autoload :Publisher, 'aws-sdk-core/client_side_monitoring/publisher'
+  end
+end
diff --git a/gems/aws-sdk-core/lib/aws-sdk-core/log.rb b/gems/aws-sdk-core/lib/aws-sdk-core/log.rb
new file mode 100644
index 00000000000..25f9adfe0f0
--- /dev/null
+++ b/gems/aws-sdk-core/lib/aws-sdk-core/log.rb
@@ -0,0 +1,10 @@
+# frozen_string_literal: true
+
+module Aws
+  # setup autoloading for Log module
+  module Log
+    autoload :Formatter, 'aws-sdk-core/log/formatter'
+    autoload :ParamFilter, 'aws-sdk-core/log/param_filter'
+    autoload :ParamFormatter, 'aws-sdk-core/log/param_formatter'
+  end
+end
\ No newline at end of file
diff --git a/gems/aws-sdk-core/lib/aws-sdk-core/plugins.rb b/gems/aws-sdk-core/lib/aws-sdk-core/plugins.rb
new file mode 100644
index 00000000000..9552af01201
--- /dev/null
+++ b/gems/aws-sdk-core/lib/aws-sdk-core/plugins.rb
@@ -0,0 +1,10 @@
+# frozen_string_literal: true
+
+module Aws
+  # setup autoloading for Plugins
+  # Most plugins are required explicitly from service clients
+  module Plugins
+    autoload :BearerAuthorization, 'aws-sdk-core/plugins/bearer_authorization'
+    autoload :SignatureV4, 'aws-sdk-core/plugins/signature_v4'
+  end
+end
\ No newline at end of file
diff --git a/gems/aws-sdk-core/lib/aws-sdk-core/resources.rb b/gems/aws-sdk-core/lib/aws-sdk-core/resources.rb
new file mode 100644
index 00000000000..d70a43b827b
--- /dev/null
+++ b/gems/aws-sdk-core/lib/aws-sdk-core/resources.rb
@@ -0,0 +1,8 @@
+# frozen_string_literal: true
+
+module Aws
+  # setup autoloading for Resources module
+  module Resources
+    autoload :Collection, 'aws-sdk-core/resources/collection'
+  end
+end
\ No newline at end of file
diff --git a/gems/aws-sdk-core/lib/aws-sdk-core/stubbing.rb b/gems/aws-sdk-core/lib/aws-sdk-core/stubbing.rb
new file mode 100644
index 00000000000..29f67cf05dd
--- /dev/null
+++ b/gems/aws-sdk-core/lib/aws-sdk-core/stubbing.rb
@@ -0,0 +1,22 @@
+# frozen_string_literal: true
+
+module Aws
+  # setup autoloading for Stubbing module
+  module Stubbing
+    autoload :EmptyStub, 'aws-sdk-core/stubbing/empty_stub'
+    autoload :DataApplicator, 'aws-sdk-core/stubbing/data_applicator'
+    autoload :StubData, 'aws-sdk-core/stubbing/stub_data'
+    autoload :XmlError, 'aws-sdk-core/stubbing/xml_error'
+
+    module Protocols
+      autoload :Json, 'aws-sdk-core/stubbing/protocols/json'
+      autoload :Rest, 'aws-sdk-core/stubbing/protocols/rest'
+      autoload :RestJson, 'aws-sdk-core/stubbing/protocols/rest_json'
+      autoload :RestXml, 'aws-sdk-core/stubbing/protocols/rest_xml'
+      autoload :Query, 'aws-sdk-core/stubbing/protocols/query'
+      autoload :EC2, 'aws-sdk-core/stubbing/protocols/ec2'
+      autoload :RpcV2, 'aws-sdk-core/stubbing/protocols/rpc_v2'
+      autoload :ApiGateway, 'aws-sdk-core/stubbing/protocols/api_gateway'
+    end
+  end
+end
\ No newline at end of file
diff --git a/gems/aws-sdk-core/lib/aws-sdk-sts/customizations.rb b/gems/aws-sdk-core/lib/aws-sdk-sts/customizations.rb
index 9f3daa3f90e..4f13f02deca 100644
--- a/gems/aws-sdk-core/lib/aws-sdk-sts/customizations.rb
+++ b/gems/aws-sdk-core/lib/aws-sdk-sts/customizations.rb
@@ -1,4 +1,8 @@
 # frozen_string_literal: true
 
 # utility classes
-require 'aws-sdk-sts/presigner'
+module Aws
+  module STS
+    autoload :Presigner, 'aws-sdk-sts/presigner'
+  end
+end
diff --git a/gems/aws-sdk-core/spec/aws/cbor/cbor_engine_spec.rb b/gems/aws-sdk-core/spec/aws/cbor/cbor_engine_spec.rb
index cfa75eb4bf3..1a6c8f13138 100644
--- a/gems/aws-sdk-core/spec/aws/cbor/cbor_engine_spec.rb
+++ b/gems/aws-sdk-core/spec/aws/cbor/cbor_engine_spec.rb
@@ -1,4 +1,5 @@
 require_relative '../../spec_helper'
+require 'aws-sdk-core/cbor/cbor_engine'
 
 module Aws
   module Cbor
@@ -75,4 +76,4 @@ def assert(actual, expected)
       end
     end
   end
-end
\ No newline at end of file
+end
diff --git a/gems/aws-sdk-core/spec/aws/cbor/decoder_spec.rb b/gems/aws-sdk-core/spec/aws/cbor/decoder_spec.rb
index 1c53353c469..916c005ba9b 100644
--- a/gems/aws-sdk-core/spec/aws/cbor/decoder_spec.rb
+++ b/gems/aws-sdk-core/spec/aws/cbor/decoder_spec.rb
@@ -1,6 +1,7 @@
 # frozen_string_literal: true
 
 require_relative '../../spec_helper'
+require 'aws-sdk-core/cbor/decoder'
 
 module Aws
   module Cbor
diff --git a/gems/aws-sdk-core/spec/aws/cbor/encoder_spec.rb b/gems/aws-sdk-core/spec/aws/cbor/encoder_spec.rb
index ce94ba9241a..abf58e2a4cc 100644
--- a/gems/aws-sdk-core/spec/aws/cbor/encoder_spec.rb
+++ b/gems/aws-sdk-core/spec/aws/cbor/encoder_spec.rb
@@ -1,6 +1,7 @@
 # frozen_string_literal: true
 
 require_relative '../../spec_helper'
+require 'aws-sdk-core/cbor/encoder'
 
 module Aws
   module Cbor
diff --git a/gems/aws-sdk-core/spec/aws/cbor_spec.rb b/gems/aws-sdk-core/spec/aws/cbor_spec.rb
index 54998f303e4..6e3a3c445c8 100644
--- a/gems/aws-sdk-core/spec/aws/cbor_spec.rb
+++ b/gems/aws-sdk-core/spec/aws/cbor_spec.rb
@@ -1,6 +1,7 @@
 # frozen_string_literal: true
 
 require_relative '../spec_helper'
+require 'aws-sdk-core/cbor'
 
 module Aws
   describe Cbor do
diff --git a/gems/aws-sdk-dynamodbstreams/lib/aws-sdk-dynamodbstreams/customizations.rb b/gems/aws-sdk-dynamodbstreams/lib/aws-sdk-dynamodbstreams/customizations.rb
index 6a2dc62b2ee..1b73b8979a0 100644
--- a/gems/aws-sdk-dynamodbstreams/lib/aws-sdk-dynamodbstreams/customizations.rb
+++ b/gems/aws-sdk-dynamodbstreams/lib/aws-sdk-dynamodbstreams/customizations.rb
@@ -1,5 +1,9 @@
 # frozen_string_literal: true
 
 # utility classes
-require 'aws-sdk-dynamodbstreams/attribute_translator'
-require 'aws-sdk-dynamodbstreams/attribute_value'
+module Aws
+  module DynamoDBStreams
+    autoload :AttributeTranslator, 'aws-sdk-dynamodbstreams/attribute_translator'
+    autoload :AttributeValue, 'aws-sdk-dynamodbstreams/attribute_value'
+  end
+end
diff --git a/gems/aws-sdk-ec2/lib/aws-sdk-ec2/customizations.rb b/gems/aws-sdk-ec2/lib/aws-sdk-ec2/customizations.rb
index dd92f4ecf76..8e9b8f90fa4 100644
--- a/gems/aws-sdk-ec2/lib/aws-sdk-ec2/customizations.rb
+++ b/gems/aws-sdk-ec2/lib/aws-sdk-ec2/customizations.rb
@@ -1,23 +1 @@
 # frozen_string_literal: true
-
-# customizations to generated classes
-require 'aws-sdk-ec2/customizations/resource'
-require 'aws-sdk-ec2/customizations/instance'
-
-Aws::EC2::Instance::Collection.extend Aws::Deprecations
-{
-  create_tags: :batch_create_tags,
-  monitor: :batch_create_tags,
-  reboot: :batch_reboot,
-  start: :batch_start,
-  stop: :batch_stop,
-  terminate: :batch_terminate!,
-  unmonitor: :batch_unmonitor,
-}.each do |old, new|
-  Aws::EC2::Instance::Collection.send(:alias_method, old, new)
-  Aws::EC2::Instance::Collection.send(:deprecated, old, use: new)
-end
-
-Aws::EC2::Tag::Collection.send(:alias_method, :delete, :batch_delete!)
-Aws::EC2::Tag::Collection.extend Aws::Deprecations
-Aws::EC2::Tag::Collection.send(:deprecated, :delete, use: :batch_delete!)
diff --git a/gems/aws-sdk-ec2/lib/aws-sdk-ec2/customizations/instance.rb b/gems/aws-sdk-ec2/lib/aws-sdk-ec2/customizations/instance.rb
index 5dc3ba19dda..f80dc11be5c 100644
--- a/gems/aws-sdk-ec2/lib/aws-sdk-ec2/customizations/instance.rb
+++ b/gems/aws-sdk-ec2/lib/aws-sdk-ec2/customizations/instance.rb
@@ -15,6 +15,23 @@ def decrypt_windows_password(key_pair_path)
         private_key.private_decrypt(decoded)
       end
 
+      class Collection < Aws::Resources::Collection
+          extend Aws::Deprecations
+
+        {
+          create_tags: :batch_create_tags,
+          monitor: :batch_create_tags,
+          reboot: :batch_reboot,
+          start: :batch_start,
+          stop: :batch_stop,
+          terminate: :batch_terminate!,
+          unmonitor: :batch_unmonitor
+        }.each do |old_method, new_method|
+          alias_method old_method, new_method
+          deprecated old_method, use: new_method
+        end
+      end
+
       private
 
       def encrypted_password
diff --git a/gems/aws-sdk-ec2/lib/aws-sdk-ec2/customizations/tag.rb b/gems/aws-sdk-ec2/lib/aws-sdk-ec2/customizations/tag.rb
new file mode 100644
index 00000000000..4979dd373b9
--- /dev/null
+++ b/gems/aws-sdk-ec2/lib/aws-sdk-ec2/customizations/tag.rb
@@ -0,0 +1,13 @@
+# frozen_string_literal: true
+
+module Aws
+  module EC2
+    class Tag
+      class Collection < Aws::Resources::Collection
+        alias_method :delete, :batch_delete!
+        extend Aws::Deprecations
+        deprecated :delete, use: :batch_delete!
+      end
+    end
+  end
+end
\ No newline at end of file
diff --git a/gems/aws-sdk-iam/lib/aws-sdk-iam/customizations.rb b/gems/aws-sdk-iam/lib/aws-sdk-iam/customizations.rb
index 18df3e09568..8e9b8f90fa4 100644
--- a/gems/aws-sdk-iam/lib/aws-sdk-iam/customizations.rb
+++ b/gems/aws-sdk-iam/lib/aws-sdk-iam/customizations.rb
@@ -1,4 +1 @@
 # frozen_string_literal: true
-
-# customizations to generated classes
-require 'aws-sdk-iam/customizations/resource'
diff --git a/gems/aws-sdk-polly/lib/aws-sdk-polly/customizations.rb b/gems/aws-sdk-polly/lib/aws-sdk-polly/customizations.rb
index 2c0111c719d..81774844718 100644
--- a/gems/aws-sdk-polly/lib/aws-sdk-polly/customizations.rb
+++ b/gems/aws-sdk-polly/lib/aws-sdk-polly/customizations.rb
@@ -1,4 +1,8 @@
 # frozen_string_literal: true
 
 # utility classes
-require 'aws-sdk-polly/presigner'
+module Aws
+  module Polly
+    autoload :Presigner, 'aws-sdk-polly/presigner'
+  end
+end
diff --git a/gems/aws-sdk-s3/lib/aws-sdk-s3/customizations.rb b/gems/aws-sdk-s3/lib/aws-sdk-s3/customizations.rb
index b16dca35841..153b80844b2 100644
--- a/gems/aws-sdk-s3/lib/aws-sdk-s3/customizations.rb
+++ b/gems/aws-sdk-s3/lib/aws-sdk-s3/customizations.rb
@@ -1,44 +1,30 @@
 # frozen_string_literal: true
 
-# utility classes
-require 'aws-sdk-s3/bucket_region_cache'
-require 'aws-sdk-s3/encryption'
-require 'aws-sdk-s3/encryption_v2'
-require 'aws-sdk-s3/file_part'
-require 'aws-sdk-s3/file_uploader'
-require 'aws-sdk-s3/file_downloader'
-require 'aws-sdk-s3/legacy_signer'
-require 'aws-sdk-s3/multipart_file_uploader'
-require 'aws-sdk-s3/multipart_stream_uploader'
-require 'aws-sdk-s3/multipart_upload_error'
-require 'aws-sdk-s3/object_copier'
-require 'aws-sdk-s3/object_multipart_copier'
-require 'aws-sdk-s3/presigned_post'
-require 'aws-sdk-s3/presigner'
+module Aws
+  module S3
+    # utility classes
+    autoload :BucketRegionCache, 'aws-sdk-s3/bucket_region_cache'
+    autoload :Encryption, 'aws-sdk-s3/encryption'
+    autoload :EncryptionV2, 'aws-sdk-s3/encryption_v2'
+    autoload :FilePart, 'aws-sdk-s3/file_part'
+    autoload :FileUploader, 'aws-sdk-s3/file_uploader'
+    autoload :FileDownloader, 'aws-sdk-s3/file_downloader'
+    autoload :LegacySigner, 'aws-sdk-s3/legacy_signer'
+    autoload :MultipartFileUploader, 'aws-sdk-s3/multipart_file_uploader'
+    autoload :MultipartStreamUploader, 'aws-sdk-s3/multipart_stream_uploader'
+    autoload :MultipartUploadError, 'aws-sdk-s3/multipart_upload_error'
+    autoload :ObjectCopier, 'aws-sdk-s3/object_copier'
+    autoload :ObjectMultipartCopier, 'aws-sdk-s3/object_multipart_copier'
+    autoload :PresignedPost, 'aws-sdk-s3/presigned_post'
+    autoload :Presigner, 'aws-sdk-s3/presigner'
 
-# s3 express session auth
-require 'aws-sdk-s3/express_credentials'
-require 'aws-sdk-s3/express_credentials_provider'
+    # s3 express session auth
+    autoload :ExpressCredentials, 'aws-sdk-s3/express_credentials'
+    autoload :ExpressCredentialsProvider, 'aws-sdk-s3/express_credentials_provider'
 
-# s3 access grants auth
-require 'aws-sdk-s3/access_grants_credentials'
-require 'aws-sdk-s3/access_grants_credentials_provider'
+    # s3 access grants auth
 
-# customizations to generated classes
-require 'aws-sdk-s3/customizations/bucket'
-require 'aws-sdk-s3/customizations/errors'
-require 'aws-sdk-s3/customizations/object'
-require 'aws-sdk-s3/customizations/object_summary'
-require 'aws-sdk-s3/customizations/multipart_upload'
-require 'aws-sdk-s3/customizations/types/list_object_versions_output'
-require 'aws-sdk-s3/customizations/types/permanent_redirect'
-
-[
-  Aws::S3::Object::Collection,
-  Aws::S3::ObjectSummary::Collection,
-  Aws::S3::ObjectVersion::Collection,
-].each do |klass|
-  klass.send(:alias_method, :delete, :batch_delete!)
-  klass.extend Aws::Deprecations
-  klass.send(:deprecated, :delete, use: :batch_delete!)
+    autoload :AccessGrantsCredentials, 'aws-sdk-s3/access_grants_credentials'
+    autoload :AccessGrantsCredentialsProvider, 'aws-sdk-s3/access_grants_credentials_provider'
+  end
 end
diff --git a/gems/aws-sdk-s3/lib/aws-sdk-s3/customizations/object.rb b/gems/aws-sdk-s3/lib/aws-sdk-s3/customizations/object.rb
index fe1bb4b0d2d..2abe7e997fc 100644
--- a/gems/aws-sdk-s3/lib/aws-sdk-s3/customizations/object.rb
+++ b/gems/aws-sdk-s3/lib/aws-sdk-s3/customizations/object.rb
@@ -559,6 +559,12 @@ def download_file(destination, options = {})
         end
         true
       end
+
+      class Collection < Aws::Resources::Collection
+        alias_method :delete, :batch_delete!
+        extend Aws::Deprecations
+        deprecated :delete, use: :batch_delete!
+      end
     end
   end
 end
diff --git a/gems/aws-sdk-s3/lib/aws-sdk-s3/customizations/object_summary.rb b/gems/aws-sdk-s3/lib/aws-sdk-s3/customizations/object_summary.rb
index 94565f01cee..8c87ddd9c24 100644
--- a/gems/aws-sdk-s3/lib/aws-sdk-s3/customizations/object_summary.rb
+++ b/gems/aws-sdk-s3/lib/aws-sdk-s3/customizations/object_summary.rb
@@ -80,6 +80,11 @@ def download_file(destination, options = {})
         object.download_file(destination, options)
       end
 
+      class Collection < Aws::Resources::Collection
+        alias_method :delete, :batch_delete!
+        extend Aws::Deprecations
+        deprecated :delete, use: :batch_delete!
+      end
     end
   end
 end
diff --git a/gems/aws-sdk-s3/lib/aws-sdk-s3/customizations/object_version.rb b/gems/aws-sdk-s3/lib/aws-sdk-s3/customizations/object_version.rb
new file mode 100644
index 00000000000..8c426be196d
--- /dev/null
+++ b/gems/aws-sdk-s3/lib/aws-sdk-s3/customizations/object_version.rb
@@ -0,0 +1,13 @@
+# frozen_string_literal: true
+
+module Aws
+  module S3
+    class ObjectVersion
+      class Collection < Aws::Resources::Collection
+        alias_method :delete, :batch_delete!
+        extend Aws::Deprecations
+        deprecated :delete, use: :batch_delete!
+      end
+    end
+  end
+end
diff --git a/gems/aws-sdk-sns/lib/aws-sdk-sns/customizations.rb b/gems/aws-sdk-sns/lib/aws-sdk-sns/customizations.rb
index 6dcda5e2743..33fd5b70e52 100644
--- a/gems/aws-sdk-sns/lib/aws-sdk-sns/customizations.rb
+++ b/gems/aws-sdk-sns/lib/aws-sdk-sns/customizations.rb
@@ -1,4 +1,8 @@
 # frozen_string_literal: true
 
 # utility classes
-require 'aws-sdk-sns/message_verifier'
+module Aws
+  module SNS
+    autoload :MessageVerifier, 'aws-sdk-sns/message_verifier'
+  end
+end
diff --git a/gems/aws-sdk-sqs/lib/aws-sdk-sqs/customizations.rb b/gems/aws-sdk-sqs/lib/aws-sdk-sqs/customizations.rb
index 190176d8cc1..2b4726b9435 100644
--- a/gems/aws-sdk-sqs/lib/aws-sdk-sqs/customizations.rb
+++ b/gems/aws-sdk-sqs/lib/aws-sdk-sqs/customizations.rb
@@ -1,4 +1,8 @@
 # frozen_string_literal: true
 
 # utility classes
-require 'aws-sdk-sqs/queue_poller'
+module Aws
+  module SQS
+    autoload :QueuePoller, 'aws-sdk-sqs/queue_poller'
+  end
+end
diff --git a/gems/aws-sdk-translate/lib/aws-sdk-translate/customizations.rb b/gems/aws-sdk-translate/lib/aws-sdk-translate/customizations.rb
index e69de29bb2d..792c6da81b4 100644
--- a/gems/aws-sdk-translate/lib/aws-sdk-translate/customizations.rb
+++ b/gems/aws-sdk-translate/lib/aws-sdk-translate/customizations.rb
@@ -0,0 +1,8 @@
+
+module Aws
+  module Translate
+    module Plugins
+      autoload :TranslateDocumentEncoding, 'aws-sdk-translate/plugins/translate_document_encoding'
+    end
+  end
+end