A kernel module to change your uptime. This kernel module has been tested with 6.0.12, but might also compile on slightlier older kernel versions.
root@vampirella:~# uptime
14:59:40 up 2:52, 4 users, load average: 0.09, 0.15, 0.21
root@vampirella:~# insmod uptime_hack.ko uptime=12345
root@vampirella:~# uptime
14:59:52 up 35 days, 17:22, 4 users, load average: 0.07, 0.14, 0.21
root@vampirella:~# echo 102021 > /sys/module/uptime_hack/parameters/uptime
root@vampirella:~# uptime
14:58:25 up 295 days, 7:03, 4 users, load average: 0.08, 0.16, 0.22
root@vampirella:~# insmod uptime_hack.ko
root@vampirella:~# lsmod| grep uptime_hack
uptime_hack 13443 0
root@vampirella:~# echo y > /sys/module/uptime_hack/parameters/hideme
root@vampirella:~# lsmod| grep uptime_hack
root@vampirella:~#
# replace linux in default.nix with the kernel package of your current booted kernel
$ nix-shell --command 'make'
$ insmod ./uptime_hack.ko
(If you don't use Nixos, you should switch)