README.md in devise-guests-0.7.0 vs README.md in devise-guests-0.8.0

@@ -1,7 +1,8 @@
 # Devise Guests
-[![Build Status](https://travis-ci.org/cbeer/devise-guests.png?branch=master)](https://travis-ci.org/cbeer/devise-guests)
+[![Tests](https://github.com/cbeer/devise-guests/actions/workflows/tests.yml/badge.svg)](https://github.com/cbeer/devise-guests/actions/workflows/tests.yml)
+[![Ruby Style Guide](https://img.shields.io/badge/code_style-standard-brightgreen.svg)](https://github.com/testdouble/standard)
 
 A drop-in guest user implementation for devise
 
 (I'm using "user" to mean my devise model, but you should be able to use any model you want, just like devise)
 
@@ -31,8 +32,62 @@
 => User<id: 1, email: ...>
 # or 
 
 guest_user # ( for anonymous users)
 
-=> User<id: nil, email: [e-mail], guest: true>
+=> User<id: 2, email: [e-mail], guest: true>
 
+```
+
+### Transferring Guest to User on Login
+
+During the login process you may want to transfer things from your guest user to the account the logged into.
+To do so, modify your ApplicationController like so:
+
+```ruby
+define_callbacks :logging_in_user
+set_callback :logging_in_user, :before, :transfer_guest_to_current_user
+
+private
+def transfer_guest_to_current_user
+  # At this point you have access to:
+  #   * current_user - the user they've just logged in as
+  #   * guest_user - the guest user they were previously identified by
+  # 
+  # After this block runs, the guest_user will be destroyed!
+  
+  if current_user.cart
+    guest_user.cart.line_items.update_all(cart_id: current_user.cart.id)
+  else
+    guest_user.cart.update!(user: current_user)
+  end
+end
+```
+
+### Custom attribute
+
+If you have added additional authentication_keys, or have other attributes on your Devise model that you need to set
+when creating a guest user, you can do so by overriding the set_guest_user_params method in your ApplicationController:
+
+```ruby
+private
+def guest_user_params
+  { site_id: current_site.id }
+end
+```
+
+### Prevent deletion of guest records
+
+By default, when signing in from a guest account to an authenticated account, the guest user is destroyed. You have an
+opportunity through the `logging_in_user` callback (or `logging_in_MODEL` if you're not using `User`) to transfer data
+from the guest to the main account before destruction occurs.
+
+However, for some situations such as guest-checkout, you may desire that any guest account which makes a purchase does
+not get destroyed. In that case you can use the `skip_destroy_guest_user` method to identify when to skip deleting these
+records. By default this method returns `false`, indicating that every record is acceptable for destruction, but you
+could use something like the following to optionally prevent it:
+
+```ruby
+def skip_destroy_guest_user
+  guest_user.orders.any?
+end
 ```