NoSQL databases are rapidly becoming the storage of choice for Web applications intended to scale. However, they trade consistency for availability. In this paper, we regain control over this trade-off by adapting an existing approach to application state, namely version control. To demonstrate that version control is applicable to the state of large-scale applications, we describe VerCASt, a version control system designed for application state and uses existing NoSQL databases to leverage their ability to store large amounts of data efficiently.