[kabiroberai]

I looked into streaming but afaict the XIP format doesn’t support random access the same way that ZIP does. specifically because 1) it doesn’t seem to have a Central Directory like ZIP and 2) it has an optimization where files can be hardlinks to other files (by ID) in the XIP, so if you want to extract a file but all you get is a hardlink ID, you can’t expand the contents until you encounter and expand the hardlink pointee. it’s possible I’ve missed something, open to ideas for sure.

[notpushkin]

I do have an idea that will add a lot of complexity for sure: you can extract Xcode, mapping out whick portions of the archive correspond to the SDKs we need, then use this mapping to only download these relevant parts, reconstruct the archive and expand it. Not sure if it’s worth it!