A generic approach for deploying and upgrading mutable software components

Deploying and upgrading software systems is typically a labourious, error prone and tedious task. To deal with the complexity of a software deployment process and to make this process more reliable, we have developed Nix, a purely functional package manager as well as an extension called Disnix, capable of deploying service-oriented systems in a network of machines. Nix and its applications only support deployment of immutable components, which never change after they have been built. However, not all components of a software system are immutable, such as databases. These components must be deployed by other means, which makes deployment and upgrades of such systems difficult, especially in large networks. In this paper, we analyse the properties of mutable components and we propose Dysnomia, a deployment extension for mutable components.