README.md in u-attributes-0.9.0 vs README.md in u-attributes-0.10.0

@@ -1,6 +1,6 @@
-# μ-attributes (Micro::Attributes)
+# μ-attributes (Micro::Attributes) [![Build Status](https://travis-ci.com/serradura/u-attributes.svg?branch=master)](https://travis-ci.com/serradura/u-attributes)
 
 This gem allows defining read-only attributes, that is, your objects will have only getters to access their attributes data.
 
 ## Installation
 
@@ -96,13 +96,13 @@
 
 person.attribute(:name) { |value| puts value } # John Doe
 person.attribute('age') { |value| puts value } # 20
 person.attribute('foo') { |value| puts value } # !! Nothing happened, because of the attribute not exists.
 
-#--------------#
-# #attribute() #
-#--------------#
+#---------------#
+# #attribute!() #
+#---------------#
 #
 # Works like the #attribute() method, but will raise an exception when the attribute not exist.
 
 puts person.attribute!('foo')                   # NameError (undefined attribute `foo)
 person.attribute!('foo') { |value| puts value } # NameError (undefined attribute `foo)
@@ -260,9 +260,102 @@
 # #attributes() #
 #---------------#
 
 p person.attributes                   # {"age"=>20, "name"=>"John Doe"}
 p Person.new(name: 'John').attributes # {"age"=>nil, "name"=>"John"}
+```
+
+## Built-in extensions
+
+You can use the method `Micro::Attributes.features()` to combine and require only the features that better fit your needs.
+
+Note: The method `Micro::Attributes.with()` is an alias for `Micro::Attributes.features()`.
+
+### Diff extension
+
+Provides a way to track changes in your object attributes.
+
+#### How to enable?
+
+```ruby
+#----------------------------------#
+# Via Micro::Attributes.features() #
+#----------------------------------#
+class Job
+  include Micro::Attributes.features(:diff)
+
+  attributes :id, state: 'sleeping'
+
+  def initialize(options)
+    self.options = options
+  end
+end
+
+# --------------------------------------------------------------------#
+# Using the .with() method alias and adding the initialize extension. #
+# --------------------------------------------------------------------#
+
+class Job
+  include Micro::Attributes.with(:initialize, :diff)
+
+  attributes :id, state: 'sleeping'
+end
+
+#---------------------------------------#
+# Via Micro::Attributes.to_initialize() #
+#---------------------------------------#
+class Job
+  include Micro::Attributes.to_initialize(diff: true)
+
+  attribute :id
+  attribute :state, 'sleeping'
+end
+```
+
+#### Usage
+
+```ruby
+require 'securerandom'
+
+class Job
+  include Micro::Attributes.features(:initialize, :diff)
+
+  attributes :id, state: 'sleeping'
+end
+
+job = Job.new(id: SecureRandom.uuid())
+
+p job.id    # A random UUID generated from SecureRandom.uuid(). e.g: "e68bcc74-b91c-45c2-a904-12f1298cc60e"
+p job.state # "sleeping"
+
+job_running = job.with_attribute(:state, 'running')
+
+p job_running.state # "running"
+
+job_changes = job.diff_attributes(job_running)
+
+#-----------------------------#
+# #present?, #blank?, #empty? #
+#-----------------------------#
+
+p job_changes.present? # true
+p job_changes.blank?   # false
+p job_changes.empty?   # false
+
+#-----------#
+# #changed? #
+#-----------#
+p job_changes.changed? # true
+
+p job_changes.changed?(:id)    # false
+
+p job_changes.changed?(:state) # true
+p job_changes.changed?(:state, from: 'sleeping', to: 'running') # true
+
+#----------------#
+# #differences() #
+#----------------#
+p job_changes.differences # {"state"=>"running"}
 ```
 
 ## Development
 
 After checking out the repo, run `bin/setup` to install dependencies. Then, run `rake test` to run the tests. You can also run `bin/console` for an interactive prompt that will allow you to experiment.