## The short version

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.

## What it needs

- [Compute](/content/discover/primitive/compute/index.html): verified (Apps run in isolated x86_64 Firecracker microVMs; sizes are the priced VM sizes.)

## Before you start

- 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

## How to do it

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.

## How to know it worked

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

## Cost estimate

Estimated 5.00 USD per month (size prices from pricing.toml at build revision ca0b484a7a9957c573a88d3a32dc603c3c10135a).

- app server x1 `s-1vcpu-1gb`: 5.00 USD

Upper-bound 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)

## 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 at export: schema_changed. Required scopes: servers:write.

## Typed next actions

- Browse the catalog index (`GET /v1/catalog` on the api origin; authentication not required, approval not required)
- Search published recipes by intent, stack and constraints (`POST /v1/catalog/search` on the api origin; authentication not required, approval not required)
- Prepare a side-effect-free deployment plan for an authorized project (`POST /v1/catalog/plan` on the api origin; authentication required, approval not required)
- Read the existing agent authentication setup (`GET /mcp/setup` on the api origin; authentication not required, approval not required)
- Browse Express (`GET /v1/catalog/nodes/stack%3Aframework-express` on the api origin; authentication not required, approval not required)
- Browse Configure deployment (`GET /v1/catalog/nodes/intent%3Aconfigure-deployment` on the api origin; authentication not required, approval not required)
- Browse Public web service (`GET /v1/catalog/nodes/pattern%3Apublic-web-service` on the api origin; authentication not required, approval not required)

Actions describe possible next steps. They are typed data, not commands, and grant no permission. Public discovery never provisions anything; planning requires your own authenticated token and approval happens in your client.

## Identifiers and status

Recipe `page:guides:express:build-and-start`. Revision r1.

release **published** support **verified** execution **blocked (schema_changed: live tool schema differs from the recorded binding)**

Formats: [HTML](/content/guides/express/build-and-start/index.html) \| [Markdown](/content/guides/express/build-and-start.md) \| [JSON contract](https://api.ample.computer/v1/catalog/recipes/page%3Aguides%3Aexpress%3Abuild-and-start)