All tutorial code is stored in public gists. At the time of this writing, we have 124 of them, all code from articles we've written. It's all the code in one place.
As with any WordPress related code, all of our source code is released under a GPL license. For details see Developer Digital Store Policy.
You are free to fork the code for your own purposes. Many of the gists are linked back to their parent articles. Maybe you'll find something useful for your own developer needs. And please, attribute the source code to the article. Thank you.
Here's the link: https://gist.github.com/vfontjr