@kballenegger checkout out the branch abstraction.  Basically I made it so it creates a class with ivars for each param in the block passed to Modernizer.new where the last variable represents the hash that will be modified.  for example 
```ruby
Modernizer.new do |env, body|
# modernization code here
end
```
will give you instance variables for env and body with body being the hash to be modified.