Chain file system

Techniques and mechanisms described herein facilitate the execution of a software program container having a plurality of layers. Each layer may include a plurality of files. For instance, a base layer may include a version of an operating system, while an upper layer may include a software program configured to run within the operating system. Different layers may store, create, or modify the same file. However, the precedence of the version of the data for the file may be based on an ordering of the layers. For example, the version of the file in a higher layer should supersede the version of the file in a lower layer. In some implementations, a privileged storage container that runs atop a virtualization layer may manage storage resources for other containers. The privileged storage container may store each file in a software program container as a snapshotable object.