Nightshift scheduling: quick launch, manual schedule, recurring

[kofort9]

Summary

Add scheduling capabilities to nightshift so runs can be triggered easily without manual tmux setup.

Three Tiers

Tier 1: Quick Launch (enhance existing zsh alias)

Add --at and --in flags to the nightshift start alias:

nightshift start                  # Start immediately (existing)
nightshift start --at 2:00        # Start at 2:00 AM tonight
nightshift start --in 1h          # Start in 1 hour
nightshift start --at 2:00 --dry-run  # Preview what would run at 2 AM

Implementation: Shell arithmetic → sleep N in a named tmux session. Same as what we do manually today, just wrapped in the alias.

Pros: Zero dependencies, works now
Cons: Dies if laptop sleeps or terminal closes

Tier 2: Manual Schedule (survives terminal close)

nightshift schedule 2:00          # One-shot: run at 2 AM tonight
nightshift schedule --cancel       # Cancel scheduled run
nightshift schedule --status       # Show next scheduled run

Implementation: Write a launchd one-shot plist to ~/Library/LaunchAgents/com.autodev.nightshift-oneshot.plist with StartCalendarInterval. Load with launchctl.

Pros: Survives terminal close, proper macOS integration
Cons: Slightly more complex, plist XML

Tier 3: Recurring Schedule

nightshift cron 2:00              # Run every night at 2 AM
nightshift cron --weekdays 2:00   # Mon-Fri only
nightshift cron --disable          # Pause recurring runs
nightshift cron --enable           # Resume
nightshift cron --status           # Show schedule + last run

Implementation: Persistent launchd plist at ~/Library/LaunchAgents/com.autodev.nightshift.plist. Runs a wrapper script that:

1. Checks if nightshift is already running (lock file)
2. Checks if there are nightshift-labeled issues to process
3. If yes, runs npx tsx nightshift/src/index.ts run
4. Logs to ~/.auto-dev/runs/

Pros: Fully autonomous, survives reboots
Cons: Need to handle edge cases (laptop sleep, network down, no issues)

Design Decisions

• launchd over cron: macOS-native, handles sleep/wake properly, can set env vars
• All three tiers coexist: Quick launch for "run this now", schedule for "run tonight", cron for "run every night"
• Single tmux session name: All tiers use nightshift session — prevents parallel runs
• Lock file: ~/.auto-dev/nightshift.lock prevents overlapping runs across tiers

Files

File	Purpose
nightshift/nightshift.zsh	Add --at, --in to start; add schedule and cron subcommands
nightshift/scripts/nightshift-launcher.sh	Wrapper for launchd (env setup, lock check, logging)
nightshift/templates/com.autodev.nightshift.plist	Template for launchd recurring plist

Verification

1. nightshift start --at 2:00 → tmux session created with correct sleep
2. nightshift schedule 2:00 → plist loaded, launchctl list | grep autodev
3. nightshift cron 2:00 → plist loaded, persists after reboot
4. Parallel run prevention: start nightshift, try starting again → blocked by lock