Commands

prewarm

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prewarm

crabbox prewarm leases a reusable box and prepares it for test runs. For SSH-backed providers it runs the same configured GitHub Actions hydration that crabbox run would otherwise do on first use; for delegated providers such as Blacksmith Testbox, hydration stays provider-owned.

crabbox prewarm
crabbox prewarm --provider azure --probe-command 'node -v && pnpm -v'
crabbox prewarm --pool example/app/main/aws/linux/c6i.2xlarge
crabbox prewarm --dry-run

The command prints the lease id and keeps the box running. Stop it with crabbox stop <id> when the test burst is done.

If Actions hydration, the optional probe, or ready-pool registration fails, prewarm automatically releases a newly created SSH lease. If automatic release cannot resolve or stop the lease, the error output prints the exact crabbox stop command to run; delegated-run providers retain their provider-owned lifecycle behavior.

#Reuse

Run follow-up commands against the printed lease id or slug:

crabbox run --id <id-or-slug> --no-sync -- pnpm test
crabbox run --id <id-or-slug> -- pnpm test

Use --no-sync when the prewarmed checkout already contains the code you want to test. Omit it when local edits must be copied; fingerprint sync should skip the upload quickly when nothing changed.

#Behavior

  • Creates a fresh lease with the normal warmup flags.
  • Runs actions hydrate when actions.workflow is configured and the provider is SSH-backed.
  • Skips hydration for delegated-run providers and reports hydration=provider-owned.
  • Optionally runs --probe-command without source sync to prove the hydrated runtime is usable.
  • Optionally registers the hydrated lease in a broker ready pool with --pool.
  • --timing-json includes hydrateMs and probeMs.

#Flags

Common lease flags such as --provider, --target, --class, --type, --market, --ttl, --idle-timeout, --slug, and --cache-volume work the same way they do on warmup.

--no-hydrate                 skip Actions hydration
--github-runner              hydrate with a GitHub self-hosted runner
--repo owner/name            GitHub repository for hydration
--workflow <file|name|id>    hydration workflow
--job <name>                 expected hydration job
--ref <ref>                  workflow ref
--wait-timeout <duration>    hydration wait timeout
--keep-alive-minutes <n>     GitHub-runner keep-alive window
--probe-command <command>    shell probe to run after hydration
--pool <key>                 register the hydrated lease in a broker ready pool
--dry-run                    print planned commands
--timing-json                print machine-readable timing

#See Also