README.md in isolator-0.11.0 vs README.md in isolator-1.0.0

@@ -99,25 +99,56 @@
   config.backtrace_filter = ->(backtrace) { backtrace.take(5) }
 
   # Define a custom ignorer class (must implement .prepare)
   # uses a row number based list from the .isolator_todo.yml file
   config.ignorer = Isolator::Ignorer
+
+  # Turn on/off raising exceptions for simultaneous transactions to different databases
+  config.disallow_cross_database_transactions = false
 end
 ```
 
 Isolator relies on [uniform_notifier][] to send custom notifications.
 
 **NOTE:** `uniform_notifier` should be installed separately (i.e., added to Gemfile).
 
+### Callbacks
+
+Isolator different callbacks so you can inject your own logic or build custom extensions.
+
+```ruby
+# This callback is called when Isolator enters the "danger zone"—a within-transaction context
+Isolator.before_isolate do
+  puts "Entering a database transaction. Be careful!"
+end
+
+# This callback is called when Isolator leaves the "danger zone"
+Isolator.after_isolate do
+  puts "Leaving a database transaction. Everything is fine. Feel free to call slow HTTP APIs"
+end
+
+# This callback is called every time a new transaction is open (root or nested)
+Isolator.on_transaction_open do |event|
+  puts "New transaction from #{event[:connection_id]}. " \
+       "Current depth: #{event[:depth]}"
+end
+
+# This callback is called every time a transaction is completed
+Isolator.on_transaction_close do |event|
+  puts "Transaction completed from #{event[:connection_id]}. " \
+       "Current depth: #{event[:depth]}"
+end
+```
+
 ### Transactional tests support
 
  - Rails' baked-in [use_transactional_tests](https://api.rubyonrails.org/classes/ActiveRecord/FixtureSet.html#class-ActiveRecord::FixtureSet-label-Transactional+Tests)
  - [database_cleaner](https://github.com/DatabaseCleaner/database_cleaner) gem. Make sure that you require isolator _after_ database_cleaner.
 
 ### Supported ORMs
 
-- `ActiveRecord` >= 5.1 (4.2 likely till works, but we do not test against it anymore)
+- `ActiveRecord` >= 6.0 (see older versions of Isolator for previous versions)
 - `ROM::SQL` (only if Active Support instrumentation extension is loaded)
 
 ### Adapters
 
 Isolator has a bunch of built-in adapters:
@@ -156,10 +187,9 @@
 ```ruby
 Isolator.adapters.sidekiq.ignore_if { Thread.current[:sidekiq_postpone] }
 ```
 
 You can add as many _ignores_ as you want, the offense is registered iff all of them return false.
-
 
 ### Using with sidekiq/testing
 
 If you require sidekiq/testing in your tests after isolator is required then it will blow away isolator's hooks, so you need to require isolator after requiring sidekiq/testing.