As your infrastructure is represented in machine-readable files, you can treat it like you do your application code. You can take the best-practice approaches to software development and apply them to your infrastructure. This means you can store it in version control (for example, Git and SVN) just like you do your code, along with the benefits that it brings:

• All changes to infrastructure are recorded in commit history
• You can review changes before accepting/merging them
• You can easily compare different configurations
• You can pick and use specific point-in-time configurations