See what drifted

admin diff

On a machine that matches its repo:

No drift: the machine matches /home/admin/arch.

After installing htop and dropping a sysctl file into /etc by hand:

Drift (as the aconfmgr lines that would describe it):
  AddPackage htop # Interactive process viewer
  CopyFile /etc/sysctl.d/99-swappiness.conf

Each line is what aconfmgr would have to add to the configuration to describe the machine as it is. Removals show up the same way, as RemovePackage or RemoveFile: something the repo has and the machine lost.

admin diff runs aconfmgr save into a throwaway copy of ~/arch/aconfmgr, so it changes nothing, and it exits 1 when there is drift – a reasonable thing to run from a timer and send to the same webhook the BOOMSTICK uses. aconfmgr prints its progress to stderr as it goes; it reads every file on the system, so expect it to take a minute or two.