"DMR" / Build SOP

What are the specific requirements for this, for an MDR, or IVDR MDSW
I heard some comments about requiring a "build SOP" to allow someone to recreate the software in its entirety but I don't think I have ever seen a dedicated SOP for building

I've written DMRs for physical products including the process descriptions, intermediates, specs and plans, but for MDSW what (and where) and the specific regs/reqs and how is it usually managed in practice, isn't a zip file of all source code and a good definition of your configuration items enough "to be able to recreate" the software.

Right, no specific requirement for a "build SOP" (emphasis added) - but you do want to have sufficient documentation to enable a re-build.

Rebuilding software can be challenging. If you don't get a snapshot of the entire set of development / build tools (including build scripts), it may not rebuild exactly the same. Given unlimited resources, I would like to capture everything and rebuild on a separate computer to ensure the build computer didn't have some libraries resident that were unexpectedly pulled in.