I would have thought the major problem after a technological collapse would be the production of computer hardware, even up to the level of something like ENIAC

I would have thought the major problem after a technological collapse would be the production of computer hardware, even up to the level of something like ENIAC, as the technology stack needed to create that represents centuries of technological development. Software development, on the other hand, took merely decades, and would be much faster to reboot, as computer language and compiler technology can be easily reinvented given information in printed books. If anything, I'd suggest an emphasis on having paper copies of books on classic programming languages and computer history widely distributed in paper libraries, and making sure that paper libraries are not displaced entirely by electronic ones. I'd consider archiving full documentation of pre-existing basic technology, rather than rolling your own; a widely distributed complete set of printed books, circuit diagrams, manuals, source code and assembly code listings capable of reproducing something like BCPL on PDP-11 might be a better choice; creating something like a PDP-11 class computer with valves or relays would be eminently feasible.