EventMachine's built-in popen does not provide access to stderr. Likewise, it's DeferrableChildProcess does not use an errback for when the process fails. This gem fixes both of those mistakes.
Deferrable Gratification (DG) facilitates asynchronous programming in Ruby, by helping create abstractions around complex operations built up from simpler ones. It helps make asynchronous code less error-prone and easier to compose. It also provides some enhancements to the Deferrable API. Features include: * fluent (aka chainable) syntax for registering multiple callbacks and errbacks to the same Deferrable. * a #bothback method for registering code to run on either success or failure. * a combinator library for building up complex asynchronous operations out of simpler ones.