How subtle magic "capture" when included in the gemfile / required in the application?
The source state in the rack contains three default servers in the following order: Thin, Puma, and WEBrick.
The rack will attempt to "mount" these three servers if the environment variables
or are not set
This behavior may change in the future, but for now, only thin and cougar will be automatically recognized when their gems are turned on.
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