Here's Bob's Coding Challenge

coding_project.rb

  state_machine :state, :initial => :applied do
    before_transition(any => :applied)    {|r, t| r.applied_at    = Time.now }
    before_transition(any => :screened)   {|r, t| r.screened_at   = Time.now }
    before_transition(any => :interview)  {|r, t| r.interview_at  = Time.now }
    before_transition(any => :rejected)   {|r, t| r.rejected_at   = Time.now }
    before_transition(any => :hired)      {|r, t| r.hired_at      = Time.now }
    before_transition(any => :disabled)   {|r, t| r.disabled_at   = Time.now }

    after_transition(any => :hired)       {|r, t| r.update_attribute(:kind, 'Employee')}

    event(:phone_screen)      { transition :applied         => :screened }
    event(:challenge_code)    { transition :screened        => :needs_exercise }
    event(:approve_exercise)  { transition :needs_exercise  => :interview }
    event(:interview)         { transition all-[:hired,:interview] => :interview }
    event(:hire)              { transition :interview       => :hired }
    event(:reject)            { transition all-[:hired]     => :rejected }
    event(:disable)           { transition :hired           => :disabled }
  end