Continuous Delivery and Scalable Agile Secret

"Continuous delivery" is hot.  Facebook recently announced that they are releasing changes twice per day, and every week they release code from 600 engineers.  Even if you don't have the same resources as Facebook, you can have a release process that is just as fast and effective.  Six months ago, we were releasing once every four weeks, and as our system got more complicated, the release cycle got slower, and we spent more time patching production bugs after each  release.  Now we release every day, or many times per day, with fewer bugs.   It's a vast improvement.  It didn't come naturally.  We had to figure out the process secret, which I can now share with you.