```ruby
#!/usr/bin/env ruby
$LOAD_PATH.unshift(File.join(File.dirname(__FILE__), '..', 'lib'))
require 'mailman'

Mailman::Application.new do

  from('%user%@%domain%') do
    puts "Got #{message.subject} from #{params[:user]}"
  end

end.run

# cat ../spec/fixtures/example01.eml | ./simple_route.rb
```

Update example to use new API
user
```ruby
#!/usr/bin/env ruby
$LOAD_PATH.unshift(File.join(File.dirname(__FILE__), '..', 'lib'))
require 'mailman'

Mailman::Application.run do

  from('%user%@%domain%') do
    puts "Got #{message.subject} from #{params[:user]}"
  end

end

# cat ../spec/fixtures/example01.eml | ./simple_route.rb
```
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