RubyMacros is a lisp-like macro pre-processor for Ruby. More than just a purely textual substitution scheme, RubyMacros can manipulate and morph Ruby parse trees (in the form of RedParse Nodes) at parse time in just about any way you see fit.
Only require delayed/job if Delayed hasn't already been defined (to prevent the vendored version of delayed_job from stomping an alternative version in a Rails app).