diff --git a/lib/paperclip.rb b/lib/paperclip.rb
index 7989ac4..e87be76 100644
--- a/lib/paperclip.rb
+++ b/lib/paperclip.rb
@@ -42,12 +42,21 @@ require 'paperclip/matchers'
 require 'paperclip/callback_compatability'
 require 'paperclip/railtie' if defined?(Rails)
 
+require 'active_support/concern'
+require 'active_support/core_ext/class/attribute'
+
 # The base module that gets included in ActiveRecord::Base. See the
 # documentation for Paperclip::ClassMethods for more useful information.
 module Paperclip
-
   VERSION = "2.2.9.2"
 
+  extend ActiveSupport::Concern
+
+  included do
+    class_attribute :attachment_definitions
+    Paperclip::CallbackCompatability.install_to(self)
+  end
+
   class << self
     # Provides configurability to Paperclip. There are a number of options available, such as:
     # * whiny: Will raise an error if Paperclip cannot process thumbnails of
@@ -109,17 +118,6 @@ module Paperclip
       File.exist?("/dev/null") ? "/dev/null" : "NUL"
     end
 
-    def included base #:nodoc:
-      base.extend ClassMethods
-      base.class_attribute :attachment_definitions
-
-      if base.respond_to?(:set_callback)
-        base.send :include, Paperclip::CallbackCompatability::Rails3
-      else
-        base.send :include, Paperclip::CallbackCompatability::Rails21
-      end
-    end
-
     def processor name #:nodoc:
       name = name.to_s.camelize
       processor = Paperclip.const_get(name)
@@ -217,11 +215,7 @@ module Paperclip
     def has_attached_file name, options = {}
       include InstanceMethods
 
-      if attachment_definitions.nil?
-        self.attachment_definitions = {}
-      else
-        self.attachment_definitions = self.attachment_definitions.dup
-      end
+      self.attachment_definitions = self.attachment_definitions&.dup || {}
       attachment_definitions[name] = {:validations => []}.merge(options)
 
       after_save :save_attached_files
@@ -258,16 +252,13 @@ module Paperclip
     # * +if+: A lambda or name of a method on the instance. Validation will only
     #   be run is this lambda or method returns true.
     # * +unless+: Same as +if+ but validates if lambda or method returns false.
-    def validates_attachment_size name, options = {}
+    def validates_attachment_size(name, **options)
       min     = options[:greater_than] || (options[:in] && options[:in].first) || 0
       max     = options[:less_than]    || (options[:in] && options[:in].last)  || (1.0/0)
-      range   = (min..max)
-      message = options[:message] || "file size must be between :min and :max bytes."
-
-      attachment_definitions[name][:validations] << [:size, {:range   => range,
-                                                             :message => message,
-                                                             :if      => options[:if],
-                                                             :unless  => options[:unless]}]
+      _add_attachment_validation(name, :size, options,
+        message: "file size must be between :min and :max bytes.",
+        range: (min..max)
+      )
     end
 
     # Places ActiveRecord-style validations on the presence of a file.
@@ -275,12 +266,8 @@ module Paperclip
     # * +if+: A lambda or name of a method on the instance. Validation will only
     #   be run is this lambda or method returns true.
     # * +unless+: Same as +if+ but validates if lambda or method returns false.
-    def validates_attachment_presence name, options = {}
-      message = options[:message] || :blank
-
-      attachment_definitions[name][:validations] << [:presence, {:message => message,
-                                                                 :if      => options[:if],
-                                                                 :unless  => options[:unless]}]
+    def validates_attachment_presence(name, **options)
+      _add_attachment_validation(name, :presence, options, message: :blank)
     end
 
     # Places ActiveRecord-style validations on the content type of the file
@@ -299,15 +286,16 @@ module Paperclip
     # NOTE: If you do not specify an [attachment]_content_type field on your
     # model, content_type validation will work _ONLY upon assignment_ and
     # re-validation after the instance has been reloaded will always succeed.
-    def validates_attachment_content_type name, options = {}
-      attachment_definitions[name][:validations] << [:content_type, {:content_type => options[:content_type],
-                                                                     :message      => options[:message],
-                                                                     :if           => options[:if],
-                                                                     :unless       => options[:unless]}]
+    def validates_attachment_content_type(name, content_type:, **options)
+      _add_attachment_validation(name, :content_type, options, content_type: content_type)
     end
 
-    def attachment_definitions
-      self.attachment_definitions
+    def _add_attachment_validation(name, type, default_options, options)
+      attachment_definitions[name][:validations] << [
+        type,
+        **options,
+        **default_options.slice(:message, :if, :unless)
+      ]
     end
   end
 
diff --git a/lib/paperclip/attachment.rb b/lib/paperclip/attachment.rb
index 8a9e604..cca3f48 100644
--- a/lib/paperclip/attachment.rb
+++ b/lib/paperclip/attachment.rb
@@ -1,5 +1,7 @@
 require 'fastimage'
 
+require 'paperclip/styles_parser'
+
 module Paperclip
   # The Attachment class manages the files for a given attachment. It saves
   # when the model saves, deletes when the model is destroyed, and processes
@@ -14,13 +16,11 @@ module Paperclip
       @default_options ||= {
         :url           => "/system/:attachment/:id/:style/:filename",
         :path          => ":rails_root/public:url",
-        :style_order   => [],
         :styles        => {},
         :default_url   => "/:attachment/:style/missing.png",
         :default_style => :original,
         :validations   => [],
         :storage       => :filesystem,
-#        :whiny         => Paperclip.options[:whiny] || Paperclip.options[:whiny_thumbnails],
         :whiny         => true,
         :restricted_characters  => /[^\w\p{Word}\d\.\-]|(^\.{0,2}$)+/,
         :filename_sanitizer     => nil
@@ -48,8 +48,7 @@ module Paperclip
       attachment_class_cache[storage].new(name, instance, options)
     end
 
-    attr_reader :name, :instance, :style_order, :styles, :default_style,
-      :convert_options, :queued_for_write, :options
+    attr_reader :name, :instance, :styles, :default_style, :queued_for_write, :options
 
     attr_accessor :post_processing
 
@@ -63,20 +62,13 @@ module Paperclip
       options = Attachment.default_options.merge(options)
 
       @url               = options[:url]
-      @url               = @url.call(self) if @url.is_a?(Proc)
       @path              = options[:path]
-      @path              = @path.call(self) if @path.is_a?(Proc)
-      @style_order       = options[:style_order]
-      @style_order       = @style_order.call(self) if @style_order.is_a?(Proc)
-      @styles            = options[:styles]
-      @styles            = @styles.call(self) if @styles.is_a?(Proc)
+      @styles            = StylesParser.new(options).styles
       @default_url       = options[:default_url]
       @validations       = options[:validations]
       @default_style     = options[:default_style]
       @storage           = options[:storage]
       @whiny             = options[:whiny_thumbnails] || options[:whiny]
-      @convert_options   = options[:convert_options] || {}
-      @processors        = options[:processors] || [:thumbnail]
       @options           = options
       @queued_for_delete = []
       @queued_for_write  = {}
@@ -86,8 +78,6 @@ module Paperclip
 
       @post_processing   = true
       @processing_url    = options[:processing_url] || @default_url
-
-      normalize_style_definition
     end
 
     # What gets called when you call instance.attachment = File. It clears
@@ -159,10 +149,6 @@ module Paperclip
       !sizes || (sizes[0] <= MAX_IMAGE_RESOLUTION && sizes[1] <= MAX_IMAGE_RESOLUTION)
     end
 
-    def most_appropriate_url
-      # stub for delayed_paperclip
-    end
-
     # Returns the public URL of the attachment, with a given style. Note that
     # this does not necessarily need to point to a file that your web server
     # can access and can point to an action in your app, if you need fine
@@ -274,18 +260,6 @@ module Paperclip
       time && time.to_i
     end
 
-    # Paths and URLs can have a number of variables interpolated into them
-    # to vary the storage location based on name, id, style, class, etc.
-    # This method is a deprecated access into supplying and retrieving these
-    # interpolations. Future access should use either Paperclip.interpolates
-    # or extend the Paperclip::Interpolations module directly.
-    def self.interpolations
-      warn('[DEPRECATION] Paperclip::Attachment.interpolations is deprecated ' +
-           'and will be removed from future versions. ' +
-           'Use Paperclip.interpolates instead')
-      Paperclip::Interpolations
-    end
-
     def sanitize_filename(file_name)
       file_name = file_name.strip
       file_name.gsub!(@options[:restricted_characters], '_') if @options[:restricted_characters]
@@ -415,48 +389,9 @@ module Paperclip
       end
     end
 
-    def normalize_style_definition #:nodoc:
-      styles.each do |name, args|
-        unless args.is_a? Hash
-          dimensions, format = [args, nil].flatten[0..1]
-          format             = nil if format.blank?
-          @styles[name]      = {
-            :processors      => @processors,
-            :geometry        => dimensions,
-            :format          => format,
-            :whiny           => @whiny,
-            :convert_options => extra_options_for(name)
-          }
-        else
-          @styles[name] = {
-            :processors => @processors,
-            :whiny => @whiny,
-            :convert_options => extra_options_for(name)
-          }.merge(@styles[name])
-        end
-      end
-    end
-
-    def solidify_style_definitions #:nodoc:
-      @styles.each do |name, args|
-        @styles[name][:geometry] = @styles[name][:geometry].call(instance) if @styles[name][:geometry].respond_to?(:call)
-        @styles[name][:processors] = @styles[name][:processors].call(instance) if @styles[name][:processors].respond_to?(:call)
-      end
-    end
-
-    def extra_options_for(style) #:nodoc:
-      all_options   = convert_options[:all]
-      all_options   = all_options.call(instance)   if all_options.respond_to?(:call)
-      style_options = convert_options[style]
-      style_options = style_options.call(instance) if style_options.respond_to?(:call)
-
-      [ style_options, all_options ].compact.join(" ")
-    end
-
     def post_process #:nodoc:
       return unless content_type.match(/image/)
       return if @queued_for_write[:original].nil?
-      solidify_style_definitions
 
       instance.run_paperclip_callbacks(:post_process) do
         instance.run_paperclip_callbacks(:"#{name}_post_process") do
@@ -466,8 +401,7 @@ module Paperclip
     end
 
     def post_process_styles #:nodoc:
-      styles_in_order = @style_order.empty? ? @styles : @styles.sort_by{|s| @style_order.index(s.first)}
-      styles_in_order.each do |name, args|
+      styles.each do |name, args|
         begin
           raise RuntimeError.new("Style #{name} has no processors defined.") if args[:processors].blank?
           @queued_for_write[name] = args[:processors].inject(@queued_for_write[:original]) do |file, processor|
diff --git a/lib/paperclip/callback_compatability.rb b/lib/paperclip/callback_compatability.rb
index eb9fe58..1e437d7 100644
--- a/lib/paperclip/callback_compatability.rb
+++ b/lib/paperclip/callback_compatability.rb
@@ -1,11 +1,14 @@
 module Paperclip
   module CallbackCompatability
-    module Rails21
-      def self.included(base)
-        base.extend(Defining)
-        base.send(:include, Running)
-      end
+    module_function
 
+    def install_to(base)
+      mod = base.respond_to?(:set_callback) ? Rails3 : Rails21
+      base.extend(mod::Defining)
+      base.send(:include, mod::Running)
+    end
+
+    module Rails21
       module Defining
         def define_paperclip_callbacks(*args)
           args.each do |callback|
@@ -28,29 +31,24 @@ module Paperclip
     end
 
     module Rails3
-      def self.included(base)
-        base.extend(Defining)
-        base.send(:include, Running)
-      end
-
       module Defining
+        TERMINATOR =
+          if Gem::Version.new(ActiveRecord::VERSION::STRING) >= Gem::Version.new('4.1')
+            ->(target, result) { result == false }
+          else
+            'result == false'
+          end
+
         def define_paperclip_callbacks(*callbacks)
-          terminator =
-            if Gem::Version.new(ActiveRecord::VERSION::STRING) >= Gem::Version.new('4.1')
-              ->(target, result) { result == false }
-            else
-              'result == false'
+          define_callbacks *[callbacks, {terminator: TERMINATOR}].flatten
+          callbacks.map(&:to_sym).each do |callback|
+            define_singleton_method "before_#{callback}" do |*args, &blk|
+              set_callback(callback, :before, *args, &blk)
+            end
+
+            define_singleton_method "after_#{callback}" do |*args, &blk|
+              set_callback(callback, :after, *args, &blk)
             end
-          define_callbacks *[callbacks, {terminator: terminator}].flatten
-          callbacks.each do |callback|
-            eval <<-end_callbacks
-              def before_#{callback}(*args, &blk)
-                set_callback(:#{callback}, :before, *args, &blk)
-              end
-              def after_#{callback}(*args, &blk)
-                set_callback(:#{callback}, :after, *args, &blk)
-              end
-            end_callbacks
           end
         end
       end
@@ -60,9 +58,7 @@ module Paperclip
           run_callbacks(callback, &block)
         end
       end
-
     end
-
   end
 end
 
diff --git a/lib/paperclip/storage/delayeds3.rb b/lib/paperclip/storage/delayeds3.rb
index 72cf2d1..f8abaac 100644
--- a/lib/paperclip/storage/delayeds3.rb
+++ b/lib/paperclip/storage/delayeds3.rb
@@ -14,9 +14,8 @@ module Paperclip
         end
 
         def parse_credentials creds
-          return @parsed_credentials if @parsed_credentials
           creds = find_credentials(creds).stringify_keys
-          @parsed_credentials ||= (creds[Rails.env] || creds).symbolize_keys
+          (creds[Rails.env] || creds).symbolize_keys
         end
 
         def find_credentials creds
@@ -33,12 +32,6 @@ module Paperclip
         end
       end
 
-      class WriteToS3Job < Struct.new(:class_name, :name, :id)
-        def perform
-          WriteToS3Worker.new.perform(class_name, name, id)
-        end
-      end
-
       class UploadWorker
         include ::Sidekiq::Worker
         sidekiq_options queue: :paperclip
@@ -81,10 +74,6 @@ module Paperclip
 
         @s3_credentials = Delayeds3.parse_credentials(@options[:s3_credentials])
         @bucket         = @options[:bucket]         || @s3_credentials[:bucket]
-        @bucket         = @bucket.call(self) if @bucket.is_a?(Proc)
-        @s3_permissions = @options[:s3_permissions] || 'public-read'
-        @s3_protocol    = @options[:s3_protocol]    || (@s3_permissions == 'public-read' ? 'http' : 'https')
-        @s3_host_alias  = @options[:s3_host_alias]
 
         @fog_provider   = @options[:fog_provider]
         @fog_directory  = @options[:fog_directory]
@@ -141,10 +130,6 @@ module Paperclip
         @bucket
       end
 
-      def s3_host_alias
-        @s3_host_alias
-      end
-
       def synced_to_s3_field
         @synced_to_s3_field ||= "#{name}_synced_to_s3".freeze
       end
@@ -166,10 +151,6 @@ module Paperclip
 
       alias_method :to_io, :to_file
 
-      def s3_protocol
-        @s3_protocol
-      end
-
       def exists?(style = default_style)
         File.exist?(filesystem_path(style))
       end
@@ -181,7 +162,8 @@ module Paperclip
       def filesystem_paths
         h = {}
         [:original, *@styles.keys].uniq.map do |style|
-          h[style] = filesystem_path(style) if File.exist?(filesystem_path(style))
+          path = filesystem_path(style)
+          h[style] = path if File.exist?(path)
         end
         h
       end
@@ -237,8 +219,9 @@ module Paperclip
         end
       end
 
-
       def flush_writes #:nodoc:
+        return if @queued_for_write.empty?
+
         @queued_for_write.each do |style, file|
           file.close
           FileUtils.mkdir_p(File.dirname(filesystem_path(style)))
@@ -247,7 +230,7 @@ module Paperclip
           FileUtils.chmod(0644, filesystem_path(style))
         end
 
-        unless @queued_for_write.empty? || (delay_processing? && dirty?)
+        unless delay_processing? && dirty?
           instance.update_column(synced_to_s3_field, false) if instance_read(:synced_to_s3)
           if instance.respond_to?(synced_to_fog_field) && instance_read(:synced_to_fog)
             instance.update_column(synced_to_fog_field, false)
@@ -285,10 +268,9 @@ module Paperclip
       def flush_deletes #:nodoc:
         # если мы картинку заливали в облака, значит мы скорее всего ее уже удалили
         # и можно не нагружать хранилище проверками
-        if !instance.is_a?(AccountFile) && instance_read(:synced_to_fog) &&
-           instance_read(:synced_to_s3)
-           @queued_for_delete = []
-           return
+        if instance_read(:synced_to_fog) && instance_read(:synced_to_s3)
+          @queued_for_delete = []
+          return
         end
 
         @queued_for_delete.each do |path|
@@ -299,7 +281,6 @@ module Paperclip
       end
 
       def delete_local_files!
-        return if instance.is_a?(AccountFile)
         instance.reload
         if instance_read(:synced_to_fog) && instance_read(:synced_to_s3)
           filesystem_paths.values.each do |filename|
diff --git a/lib/paperclip/storage/filesystem.rb b/lib/paperclip/storage/filesystem.rb
index 8662eae..39cb911 100644
--- a/lib/paperclip/storage/filesystem.rb
+++ b/lib/paperclip/storage/filesystem.rb
@@ -34,10 +34,11 @@ module Paperclip
       def flush_writes #:nodoc:
         @queued_for_write.each do |style, file|
           file.close
-          FileUtils.mkdir_p(File.dirname(path(style)))
-          log("saving #{path(style)}")
-          FileUtils.mv(file.path, path(style))
-          FileUtils.chmod(0644, path(style))
+          filename = path(style)
+          FileUtils.mkdir_p(File.dirname(filename))
+          log("saving #{filename}")
+          FileUtils.mv(file.path, filename)
+          FileUtils.chmod(0644, filename)
         end
         @queued_for_write = {}
       end
diff --git a/lib/paperclip/styles_parser.rb b/lib/paperclip/styles_parser.rb
new file mode 100644
index 0000000..2359464
--- /dev/null
+++ b/lib/paperclip/styles_parser.rb
@@ -0,0 +1,42 @@
+module Paperclip
+  class StylesParser
+    attr_reader :styles, :convert_options, :processors, :whiny
+
+    def initialize(options)
+      @styles = options[:styles]
+      @convert_options = options[:convert_options] || {}
+      @processors = options[:processors] || [:thumbnail]
+      @whiny = options[:whiny_thumbnails] || options[:whiny]
+
+      normalize_style_definition
+    end
+
+    def normalize_style_definition #:nodoc:
+      styles.each do |name, args|
+        styles[name] =
+          if args.is_a? Hash
+            {
+              processors:       processors,
+              whiny:            whiny,
+              convert_options:  extra_options_for(name)
+            }.merge(args)
+          else
+            dimensions, format = args
+            {
+              processors:       processors,
+              geometry:         dimensions,
+              format:           format.presence,
+              whiny:            whiny,
+              convert_options:  extra_options_for(name)
+            }
+          end
+      end
+    end
+
+    def extra_options_for(style) #:nodoc:
+      all_options   = convert_options[:all]
+      style_options = convert_options[style]
+      [style_options, all_options].compact.join(' ')
+    end
+  end
+end
diff --git a/paperclip.gemspec b/paperclip.gemspec
index be76b92..4818a22 100644
--- a/paperclip.gemspec
+++ b/paperclip.gemspec
@@ -17,5 +17,6 @@ Gem::Specification.new do |s|
   s.rubygems_version = %q{1.3.1}
   s.summary = %q{File attachments as attributes for ActiveRecord}
 
+  s.add_dependency 'activesupport'
   s.add_dependency 'fastimage'
 end