```ruby
require "coveralls"
Coveralls.wear!

require "periscope"

Dir["./spec/shared/*.rb"].each { |f| require f }
Dir["./spec/support/*.rb"].each { |f| require f }

# Respect explicitly set adapter or infer based on active gemfile
adapter, gemfile = ENV["ADAPTER"], ENV["BUNDLE_GEMFILE"]
adapter ||= gemfile && gemfile[%r(gemfiles/(.*?)/)] && $1

if adapter
  require "periscope/adapters/#{adapter}"
  Dir["./spec/support/adapters/#{adapter}/*.rb"].each { |f| require f }
end

RSpec.configure do |config|
  config.filter_run(adapter: adapter)
end
```

Set up SimpleCov to merge results of adapter-specific tests
user
```ruby
require "simplecov"
require "coveralls"

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

adapter, gemfile = ENV["ADAPTER"], ENV["BUNDLE_GEMFILE"]
adapter ||= gemfile && gemfile[%r(gemfiles/(.*?)/)] && $1

SimpleCov.command_name(adapter)
SimpleCov.start do
  add_filter("spec")
end

require "periscope"

Dir["./spec/shared/*.rb"].each { |f| require f }
Dir["./spec/support/*.rb"].each { |f| require f }

if adapter
  require "periscope/adapters/#{adapter}"
  Dir["./spec/support/adapters/#{adapter}/*.rb"].each { |f| require f }
end

RSpec.configure do |config|
  config.filter_run(adapter: adapter)
end
```
assistant