```ruby
# encoding: utf-8

# SimpleCov MUST be started before require 'dm-mapper'
#
if ENV['COVERAGE']
  require 'simplecov'

  SimpleCov.start do
    command_name 'spec:unit'

    add_filter "spec"
    add_filter "config"
    add_filter "lib/data_mapper/support"

    add_group "Finalizer",    "lib/data_mapper/finalizer"
    add_group "Mapper",       "lib/data_mapper/mapper"
    add_group "Relation",     "lib/data_mapper/relation"
    add_group "Relationship", "lib/data_mapper/relationship"
    add_group "Attribute",    "lib/data_mapper/attribute"
  end

end

require 'shared_helper' # requires dm-mapper
```

Add coveralls to unit spec coverage
user
```ruby
# encoding: utf-8

# SimpleCov MUST be started before require 'dm-mapper'
#
if ENV['COVERAGE'] == 'true'
  require 'simplecov'
  require 'coveralls'

  SimpleCov.formatter = SimpleCov::Formatter::MultiFormatter[
    SimpleCov::Formatter::HTMLFormatter,
    Coveralls::SimpleCov::Formatter
  ]

  SimpleCov.start do
    command_name 'spec:unit'

    add_filter 'config'
    add_filter 'lib/data_mapper/support'
    add_filter 'spec'

    add_group 'Finalizer',    'lib/data_mapper/finalizer'
    add_group 'Mapper',       'lib/data_mapper/mapper'
    add_group 'Relation',     'lib/data_mapper/relation'
    add_group 'Relationship', 'lib/data_mapper/relationship'
    add_group 'Attribute',    'lib/data_mapper/attribute'

    minimum_coverage 98.21
  end

end

require 'shared_helper' # requires dm-mapper
```
assistant