gem dependency eventmachine --reverse-dependencies
rake-compiler (~> 0.9.5, development)
rake-compiler-dock (~> 0.5.1, development)
test-unit (~> 2.0, development)
excon-0.51.0 (eventmachine (>= 1.0.4, development))
thin-1.7.0 (eventmachine (>= 1.0.4, ~> 1.0))
I wanted to find out what is depending on eventmachine in my project. Because, concurrent-ruby is a better alternative to eventmachine. My suspicion was that sucker_punch gem was using it. I was wrong because as you see in the about output, it is not the culprit. The version 2.0 of sucker punch uses concurrent-ruby. Luckily, only the development environment has dependency on the eventmachin gem.