A Dead PID Held My Lock for 2 Hours: One Missing Line, Zero Output, exit 0 Every Time

For 30 straight days as a college student earning ¥100k/month, I posted to Instagram by hand, and then I burned out and stopped. Today the same job runs on a Claude Code autonomous environment, I touch nothing, and it holds up ¥1.2M/month in revenue. Except for the two hours when it quietly stopped: three consecutive launchd runs, zero pieces of content generated, last exit=0 every single time, and not one alert. The cause was a process that had already been killed, holding a lock file nobody would take away from it. Why this setup works From "doing the work" to "building the environment" The problem with updating social media by hand is that it burns willpower. No matter how motivated you are, sleep, health, and mood all fluctuate. During the period when I was laid off and my income went to zero, I had no mental slack for posting at all. The autonomous environment I spent six months building with Claude Code runs regardless of my emotional state. launchd calls a script, the script generates content with claude -p (MAX plan quota; paid APIs are off-limits), the output is queued for auto-posting, and it goes out to Instagram every day at 19:30. As long as this machinery keeps working, ¥1.2M/month in sales holds up without me lifting a finger. The mental model I want to hand you A lot of people think "automation = writing scripts," and that's only half right. A script is correct at the moment you write it. Given time, external dependencies break, processes die for reasons you didn't anticipate, and lock files turn into debris that blocks every future run. An autonomous environment that actually works is one that assumes breakage and carries a layer that repairs it. The lock story here is a textbook case. ~/dev/brand-404/sns/gen_feature.py is a script launched on a schedule by launchd that auto-generates Instagram feature articles. A single run takes a long time (up to three claude -p calls, plus image generation, adding up to tens of minutes), so it has a lock mechani