page:guides:express:deployment diagnostics

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.

Representative Queries

• Diagnose deployment failures for Express
• Where can I host Diagnose deployment failures built with Express?
• I need framework-specific failure signatures and validation checks using only actual available observability interfaces.

Resource Requirements

• primitive:compute

Infrastructure Requirements

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

Framework

Express

Workload

Diagnose deployment failures

Release Status

Published

Support Status

Verified

Execution Status

Unbound

Docs Only

true

Prerequisites

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

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

Workflow 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.
   Command: ample logs --kind build
3. Read the runtime log
   For a live-but-misbehaving app the runtime log shows the process output.
   Command: ample logs --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.

Examples

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

Success Checks

• Expectation: ample logs --kind build shows the failure line Description: build log contains the failing command output
  Kind: manual

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.

Evidence Summary

• Canary Run:
  Summary: An intentionally failing build was rejected synchronously with build_failed and the failure line was readable in the build log.
  Observed At: 2026-09-19T23:55:33Z
  Implementation Revision: 1764076-tls-account-903d345
  Expires At: 2027-03-18T23:55:33Z
  Scope:

  • CLI Version: 0.1.20
  • Platform: hosted-beta
  • Template: node-22

• Canary Run:
  Summary: Express app with npm install and npm run start deployed on the node-22 template; the public URL served the expected response.
  Observed At: 2026-09-19T23:55:33Z
  Implementation Revision: 1764076-tls-account-903d345
  Expires At: 2027-03-18T23:55:33Z
  Scope:

  • CLI Version: 0.1.20
  • Platform: hosted-beta
  • Template: node-22

Last Verified At

2026-09-19T23:55:33Z

Unknowns

• Pricing for this recipe is unknown.
• Region availability is unknown until a verified region fact is recorded.
• Compliance attestations are unknown; none are claimed.