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: 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

{
  "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"
}