One small part per post: a probe, a daily job, a trick, a trap that cost an afternoon.
Scheduled jobs on a Mac belong in a launchd plist: they survive reboots, run as your user, and log where you can find them. One minimal plist, the commands to load it, and the privacy gotcha that makes a job under Documents fail with Operation not permitted.
A few machines in my Tailscale network run unattended. Instead of naming each one in the access rules, they carry one tag, and the rules talk about the tag: who may reach them, on which ports, who may SSH in. Adding a machine stops being a policy edit.
A folder of source material, a scheduled job that turns one item into an article each morning and publishes it, and a human who reads every post for the first week before the job is allowed to run alone.
launchctl kickstart -k restarts a launchd job with the configuration it already has in memory. Edit the plist, kickstart, and the service comes back running the old settings while looking freshly restarted. How it bites and the two lines that fix it.
Every ten minutes a script loads a product's checkout page and checks that the pay button is there. It posts to a chat channel exactly twice per incident: once when it goes down, once when it comes back. Never in between.
Lead forms on Meta collect names all night and show them in a dashboard nobody opens. A short scheduled script pulls yesterday's leads, writes a clean CSV and mails it before the client's first coffee.
