What would that involve? I'm guessing making a bookable SD card that dumps memory, unplugging and quickly replugging the power cable, and then booting that card? Or do you need something more specialized?

I don't think that you can, manually, swap SD cards (on a running system! That alone would trigger all sorts of quirks, unless you're running off initramfs, tmpfs or an external storage device.) and toggle power so quickly that the RPi reboots but doesn't erase RAM. I mean, you might get very lucky, but the boot process is heavily stacked against you - the bootloader on your SD card gets executed fairly late in the boot sequence: https://raspberrypi.stackexchange.com/questions/10442/what-i...

I meant you'd swap the card when the system was off, not when it was on.

Power off, swap cards, power on? That's a multi-second task, even if SDRAM didn't reset during boot stages.

I mean, you could swap the cards live, but I'd be worried about the electrical end, not the debounced and processed signals coming from the OS - although if I were writing a malicious package, device tree changes would also trigger all sorts of alarms. (Had a bad contact on an SD card once - the effect of disconnect-reconnect on the running OS was...spectacular, but in a bad way. In the better case, it fluctuated the board voltage enough to reboot.)

My thoughts as well. Great job regardless, someone is in trouble! :/