Embodiments of the invention include systems and methods for providing writable snapshot functionality for file systems. Pointer-based snapshots can be taken of an active version of the file system resulting in either (1) a read-only snapshot image and a new active version of the file system resulting from a read-only snapshot operation; or (2) a read-only snapshot image and two new active versions of the file system resulting from a writable snapshot operation. The two active file systems generated from writable snapshot operations are each independently and concurrently writable. Various techniques are also presented for handling multiple, concurrently active file systems. For example, novel techniques are described for allowing snapshot restore, compaction, and other functionality to operate in an environment having multiple read-only and writable versions of the file system.