Configure build and start for Express

Summary

Configure build and start for an Express app on Ample. Ample detects Node, runs npm install and npm run build --if-present, and starts the app with npm run start on the node-22 template; the app only has to bind 0.0.0.0 on PORT.

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 package.json with a start script
• A server that listens on process.env.PORT and 0.0.0.0
• An Ample account token with servers:write

Exact tested configuration

• template: node-22
• runtime: node
• size: s-1vcpu-1gb
• install: npm install
• build: echo no build needed
• start: npm run start

Steps

1. Pin what detection cannot infer. If the start command is not in package.json, pass --start, or write it into ample.toml with ample plan --write.

2. Deploy. Run the existing synchronous deploy once from the project directory and read the result. Exit 0 is live, 1 is failed, 2 is blocked on a required preflight action. Re-running with no change is a content-addressed no-op.

   ample deploy . --name <app-name> --public --format json
   

3. Verify. Fetch the live URL and run the success checks below. On failure read the build log, then the runtime log, fix the cause and deploy again; do not blind-retry.

   ample logs <deployment_id> --kind build
   

Tested examples

• Express basic canary (tests/deploy-canaries/express-basic): Minimal Express server deployed with the detected npm install / npm run start commands.

Success checks

• root route responds (/ on the live URL, expect ample canary express basic)

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.
• A missing package-lock.json produces a warning and a slower, non-reproducible install.

Cost estimate

Estimated 5.00 USD per month (size prices from pricing.toml at build revision a1b8c38919e59cd035ebabaced73cf84ece24371).

• app server x1 s-1vcpu-1gb: 5.00 USD

Apps and managed databases auto-pause when idle; the estimate is the always-on monthly price of the tested sizes. Plan quotas and budgets apply.

Verification evidence

• 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

MCP tool ample_deploy (registry mcp:ample_deploy), schema hash 876465fce906da0c observed 2026-09-20T01:55:48.667900+00:00 at revision 199ff1dfd526, binding state current, required scopes: servers:write.