Diagnose deployment failures for Express

Summary

Diagnose a failed Express deployment on Ample. Deploy is synchronous: a build failure returns build_failed with the deployment id, and ample logs exposes the build log and then the runtime log so the cause is read, not guessed.

Infrastructure requirements

• Compute: verified (Apps run in isolated x86_64 Firecracker microVMs that auto-pause when idle and wake on request; sizes are the priced VM sizes.)

Prerequisites

• A deployment id from a failed ample deploy
• An Ample account token with servers:read

Exact tested configuration

• template: node-22
• runtime: node
• size: s-1vcpu-1gb
• install: npm install
• build: printf 'ample-build-failure-probe' >&2 && false
• start: npm run start

Steps

1. Read the failure code. Exit 1 with build_failed means the isolated build failed; exit 2 means a required preflight action is blocking.
2. Read the build log. The last lines name the failing command.

   ample logs <deployment_id> --kind build

3. Read the runtime log. For a live-but-misbehaving app the runtime log shows the process output.

   ample logs <deployment_id> --kind runtime

4. Fix and redeploy once. Change the source or the command override, then run ample deploy again. Do not loop deploys to poll status.

Tested examples

• Intentional build failure canary (tests/deploy-canaries/node-package-no-lock (build-and-list-failure)): A failing build command is rejected synchronously and its stderr line appears in the build log.

Success checks

• build log contains the failing command output

Limitations

• Verified on the node-22 template at s-1vcpu-1gb; other templates and sizes are not verified by this recipe.
• Region, compliance attestations and request-duration limits are unknown and not claimed.
• Apps auto-pause when idle and wake on the next request; always-on is an operator setting, not a plan feature.
• This guide is documentation only; diagnosis is reading logs, and no tool is executed automatically by the catalog.

Cost estimate

Unknown. No price is claimed for this recipe.

Verification evidence

• canary_run on 2026-09-19T23:55:33Z at revision 1764076-tls-account-903d345: An intentionally failing build was rejected synchronously with build_failed and the failure line was readable in the build log. (expires 2027-03-18T23:55:33Z)
• canary_run on 2026-09-19T23:55:33Z at revision 1764076-tls-account-903d345: Express app with npm install and npm run start deployed on the node-22 template; the public URL served the expected response. (expires 2027-03-18T23:55:33Z)

Last verified: 2026-09-19T23:55:33Z

Execution binding

No execution binding. This recipe is documentation only; nothing is executed automatically.