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Cron Jobs

Hydra uses a long-running supervisor daemon for build + review dispatch. A small number of cron jobs keep the daemon alive and handle periodic housekeeping.

Setup​

# Install the crontab
(crontab -l 2>/dev/null; cat <<'CRON'
* * * * * /path/to/hydra/scripts/watchdog-supervisor.sh >> /path/to/hydra/logs/watchdog.log 2>&1
*/10 * * * * /path/to/hydra/scripts/reconcile.sh >> /path/to/hydra/logs/reconcile.log 2>&1
*/30 * * * * /path/to/hydra/scripts/cron-audit.sh >> /path/to/hydra/logs/audit-cron.log 2>&1
*/10 * * * * /path/to/hydra/scripts/cron-spec-from-issue.sh >> /path/to/hydra/logs/spec-from-issue.log 2>&1
15 * * * * /path/to/hydra/scripts/cron-update-prs.sh >> /path/to/hydra/logs/update-prs-cron.log 2>&1
CRON
) | crontab -

Replace /path/to/hydra with the actual path (e.g., /home/wilco/hydra).

Cron Jobs​

ScriptIntervalWhat it does
watchdog-supervisor.shEvery minuteStarts hydra-supervisor.sh if the daemon is not running
reconcile.shEvery 10 minLabel validation + auto-recovery sweep
cron-audit.shEvery 30 minFull codebase audits on ready-for-audit issues
cron-spec-from-issue.shEvery 10 minConverts needs-spec issues into OpenSpec changes
cron-update-prs.shEvery hourMerges development into open feature/<issue>/* PRs that are BEHIND

scripts/cron-hydra.sh is retained for manual dispatch runs but is not scheduled — the supervisor replaces it.

Logs​

FileContent
logs/cron.logBuild pipeline dispatch log
logs/review-cron.logReview dispatch log
logs/pipeline-{issue}-{timestamp}/Per-pipeline stage logs (builder, quality, reviewer, etc.)
logs/reviews/{repo}-{pr}-{type}-{timestamp}.jsonlPer-review JSONL output

Trigger Label Configuration​

The label that triggers the build pipeline is configurable via the HYDRA_TRIGGER_LABEL environment variable. Default: ready-to-build.

Set it in secrets/.env:

HYDRA_TRIGGER_LABEL=wilco-testing

Or pass it as an environment variable when running scripts directly:

HYDRA_TRIGGER_LABEL=my-custom-label ./scripts/orchestrate.sh --poll --repo-url https://github.com/ConductionNL/myapp

Or use the --trigger-label flag with orchestrate.sh:

./scripts/orchestrate.sh --issue-url ... --repo-url ... --trigger-label my-custom-label

This is useful for:

  • Testing: Use a separate label (e.g. wilco-testing) to avoid interfering with production pipelines
  • Multi-environment isolation: Run separate Hydra instances that each watch for different labels
  • Gradual rollout: Only process issues you explicitly opt in

Build cron (cron-hydra.sh)​

  • Searches all open issues with the trigger label (default: ready-to-build) across the org
  • Dispatches pipelines in background (detached), up to 5 parallel slots
  • Each slot gets an isolated NC port (8086-8090) and container namespace
  • Exits immediately — pipelines continue in background
  • Lock files in /tmp/hydra-slots/ prevent double-dispatch

Review dispatch (supervisor)​

Review dispatch is handled continuously by hydra-supervisor.sh, not a cron entry.

  • Supervisor scans open PRs for review labels across the org each cycle
  • Uses the shared slot pool (max 5 concurrent with builders)
  • Labels are on PRs (not issues) — this is how reviews work standalone
  • After a reviewer posts its verdict, the label is removed
  • Works independently from the build pipeline — any repo in the org can use it

Standalone review usage​

For a one-off manual review on a specific PR, use scripts/manual-review.sh:

./scripts/manual-review.sh \
    --pr-url https://github.com/ConductionNL/myapp/pull/42 \
    --review-type code

Results appear as PR comments.

Verify cron is running​

# Check crontab
crontab -l

# Check supervisor is alive
pgrep -f hydra-supervisor.sh

# Check recent logs
tail -20 /path/to/hydra/logs/supervisor.log
tail -20 /path/to/hydra/logs/watchdog.log
tail -20 /path/to/hydra/logs/reconcile.log

# Check active slots
ls /tmp/hydra-slots/slot-*.lock 2>/dev/null

Troubleshooting​

SymptomFix
Cron not runningCheck crontab -l, verify PATH in script header
No PRs with review labels foundExpected when no reviews are pending
Review label not removedCheck logs/reviews/ for container errors
Stale slot lockrm /tmp/hydra-slots/slot-N.lock (cron auto-detects dead PIDs)