Easing software component repository evolution

International audienceModern software systems are built by composing components drawn from large repositories, whose size and complexity increase at a fast pace. Maintaining and evolving these software collections is a complex task, and a strict qualification process needs to be enforced. We studied in depth the Debian software repository, one of the largest and most complex existing ones, and we developed comigrate, an extremely efficient tool that is able to identify the largest sets of components that can migrate to the reference repository without violating its quality constraints. This tool outperforms significantly all existing tools, and provides detailed information that is crucial to understand the reasons why some components cannot migrate. Extensive validation on the Debian distribution has been performed. The core architecture of the tool is quite general, and can be easily adapted to other software repositories