module Kernel

def quietly

This method is not thread-safe.

quietly { system 'bundle install' }

Silences both STDOUT and STDERR, even for subprocesses. 
def quietly
  ActiveSupport::Deprecation.warn(
    "`#quietly` is deprecated and will be removed in the next release."
  ) #not thread-safe
  silence_stream(STDOUT) do
    silence_stream(STDERR) do
      yield
    end
  end
end