Hi Jeremiah.

What is the PureOS < > Debian delta? I assume that it is a set of patches that we apply to packages, like the work Jonas does on Firefox

These patches should canonically be in the source.puri.sm repositories:

https://source.puri.sm/pureos/packages

For example, here is a patch of mine to Gimp:

https://source.puri.sm/pureos/packages/gimp/blob/10711bb1ccbf9be950445a6a6ba...

[…] as well as the fact that we do not have a non-free repo.

These parts of "negative space" are less obvious. Whilst you mention the absense of the non-free repository we also have removed other specific packages from "main". I am unsure how to canonically generate such a list from our archive software, but it is likely possible with some grep-dctrl foo and a quick refresher on set theory.

In addition, there is the delta in unmodified packages that we have migrated from unstable, which additionally add to the delta from Debian buster. This could be a refinement othe programming task outlined in my previous paragraph if one was inclined to locate the exact answer.

Knowing the delta would help us to understand how to move the work being done on the L5 phone into our CD system for example

Can you elaborate on this, just out of interest? In particular, what is specific about the CD system that I am perhaps missing?

Best wishes,