How to speed up your rspec execution

before_all_tip.rb

before(:all)  { @stuff = create :stuff                                  }
let!(:stuff)  { @stuff                                                  }
before        { Stuff.stub(:find).with(stuff.id.to_s).and_return(stuff) }

build_stubbed.rb

let!(:stuff) { build_stubbed :stuff                                    }
before       { Stuff.stub(:find).with(stuff.id.to_s).and_return(stuff) }