Architecture Cross-Grading Support in Debian

Description of the project:

Debian is well-known for its wide support for multiple architectures. We build the vast majority of our packages for all out architectures, and adding extra libraries or programs for another architecture is easy, supported directly by the packaging system. It's often even possible to directly run programs from an incompatible architecture by using qemu-user-static on a Debian system. (Ask me more about this at some point!)

However, despite all of this support it's still quite hard to do one thing in Debian - cross-grade a system from one architecture to another. Due to this, lots of people are still running older 32-bit "i386" systems on top of 64-bit hardware (as an example). It is possible to cross-grade, but it's currently a very risky manual process - it's not for the faint-hearted. This project would involve developing (and testing!) tools to make cross-grading a supported Debian feature.