# Configure build and start for Spring Boot

## Summary

Build and start for a Spring Boot app on Ample. Verified on Spring Boot: the app built and started with the documented commands and answered on its public HTTPS URL. Build and start: `./mvnw -q -DskipTests package` (or the Gradle wrapper) producing one application jar, then `java -jar` on the jvm-21 template (Temurin JDK 21) with `server.port` read from `PORT`.

## Infrastructure requirements

- [Compute](/discover/primitive/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 Spring Boot project (`./mvnw -q -DskipTests package` (or the Gradle wrapper) producing one application jar, then `java -jar` on the jvm-21 template (Temurin JDK 21) with `server.port` read from `PORT`)
- An Ample account token with `servers:write`

## Exact tested configuration

- template: `jvm-21`
- runtime: `java`
- size: `s-1vcpu-2gb`
- build: `./mvnw -q -DskipTests package`
- start: `java -jar $(ls target/*.jar | grep -v -- '-plain' | head -n 1)`

## Steps

1. **Build and start.** `./mvnw -q -DskipTests package` (or the Gradle wrapper) producing one application jar, then `java -jar` on the jvm-21 template (Temurin JDK 21) with `server.port` read from `PORT`; the server must bind `0.0.0.0` on `PORT`.
2. **Deploy.** Run the synchronous deploy once and read the result.
   
   ```
   ample deploy . --name <app-name> --public
   ```
3. **Verify.** Fetch the live URL on the example; on failure read the build and runtime logs.
   
   ```
   ample logs <deployment_id> --kind build
   ```

## Tested examples

- **Spring Boot pattern fixture** (tests/deploy-canaries/spring-boot-patterns): Verified build and start on Spring Boot.

## Success checks

- app responds on its public URL (`/` on the live URL, expect ample canary spring boot patterns)

## Limitations

- Verified on the jvm-21 template at `s-1vcpu-2gb`; other sizes and Spring Boot major versions are not verified.
- Region, compliance attestations and request-duration limits are unknown and not claimed.

## 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

Always-on monthly price of the tested sizes; apps auto-pause when idle. Buckets are allocation-priced per quota and not included.

## Verification evidence

- canary_run on 2026-09-21T02:34:39Z at revision `1d28ae0-dirty (CLI 0.1.21)`: Spring Boot pattern fixture deployed on Ample (`./mvnw -q -DskipTests package` (or the Gradle wrapper) producing one application jar, then `java -jar` on the jvm-21 template (Temurin JDK 21) with `server.port` read from `PORT`); for this guide: the app built and started with the documented commands and answered on its public HTTPS URL. (expires 2027-03-20T02:34:39Z)

Last verified: 2026-09-21T02:34:39Z

## Execution binding

MCP tool `ample_deploy` (registry `mcp:ample_deploy`), schema hash `876465fce906da0c` observed 2026-09-21T03:19:59.461917+00:00 at revision `49962bcade4f`, binding state `current`, required scopes: `servers:write`.

## Input schema

```json
{
  "additionalProperties": false,
  "properties": {
    "env": {
      "description": "Encrypted environment variables",
      "items": {
        "pattern": "^[A-Z][A-Z0-9_]*=.*$",
        "type": "string"
      },
      "maxItems": 50,
      "type": "array"
    },
    "name": {
      "description": "App name",
      "maxLength": 63,
      "minLength": 1,
      "pattern": "^[a-z0-9-]+$",
      "type": "string"
    },
    "path": {
      "description": "Project directory or ample.toml service",
      "maxLength": 512,
      "minLength": 1,
      "type": "string"
    },
    "release_command": {
      "description": "Migration command run before activation",
      "maxLength": 512,
      "type": "string"
    }
  },
  "required": [
    "name",
    "path"
  ],
  "type": "object"
}
```