Til

rsync built on cygwin doesn’t understand windows drive letters. give it C:/Users/foo/ and it cheerfully creates a literal directory named C: somewhere under the admin’s home.

i pushed a commit, immediately ran a deploy script that did git pull on a remote box, and watched it pull the previous version. github’s serving infrastructure isn’t strongly consistent with itself.

tried to add a reconnection wait inside a macOS CGEventTap callback. macOS killed the tap within seconds. event handlers must return immediately — always.

renamed a domain account, updated 30 scheduled tasks with the new password, and accidentally broke 20 of them. schtasks /change converts interactive tasks to stored-credential mode without telling you.

macOS quietly cleans /var/tmp between reboots. we had 12 scheduled jobs storing their config there. you can guess what happened.

GPT-5 mini started refusing our heartbeat prompt. each refusal was saved to the transcript. the next run saw the prior refusals and refused harder. a self-reinforcing context poisoning loop that ran silently for a week.

Electron’s safeStorage uses DPAPI on Windows, which means any process running as your user can decrypt Signal’s database. on macOS, Keychain actually isolates per-app.

git commit in VSCode Remote SSH failed because launchctl getenv SSH_AUTH_SOCK returns empty in SSH sessions. the fix was a stable symlink.

building a location tracker led me to google plus codes. they’re open source, unlike what3words, and genuinely useful.