looking for a backpack that can fit 3-7 days worth of clothes, where the luggage compartment can zip off fully, leaving just a laptop-sized backpack (laptop + headphones + jacket)

ideally waterproof

something like this: https://www.amazon.com/MACWE-Large-Travel-Backpack-for-Men-Airline-Approved-Carry-On-Backpack-with-Detachable-Laptop-Bag-Expandable-Weekender-Backpack-Navy/dp/B0BF8QY7HD

but reversed: the detachable laptop bag should have straps and the luggage part should zip on to it

hypertext veteran • /mud core dev @lattice

Not sure it fits all your requirements, but Minaal makes awesome travel packs.

Not sure it fits all your requirements, but Minaal makes awesome travel packs.

https://www.minaal.com/

You can take a look at the north face backpacks, heard many good things about it 

Can't find a specific model though