UPDATE:
Sparkler is safe, it isn’t affected by the Sparkle RCE (Remote Code Execution) ┬ávulnerability

http://appleinsider.com/articles/16/02/09/sparkle-software-updater-opens-mac-to-attack

So, You just finished the new features and bug fixes and ready to release your next version of your awesome OS X app which you choose to deliver and distribute outside the Apple’s App Store. 365 more words