Example methods and systems are directed to a multitenant application server using a union file system. Each tenant has one or more users and a tenant layer in the union file system. Each user has a user layer in the union file system. The union file system provides a logical file system to each user based on the user layer, the tenant layer, and a base layer comprising a set of application layers. A first user shares an application template file with other users of the same tenant by moving the file from the first user's user layer to the tenant layer. After the file is moved, all users of the tenant have access to the application defined by the application template file. The moving of the file is achieved by modifying metadata for the file.