Host mobile backend with Spring Boot: Postgres-backed state

Summary

Deploy a mobile backend built with Spring Boot on Ample using the durable job state pattern. Compute runs the app in an isolated microVM behind a public HTTPS URL, a managed PostgreSQL 16 database is auto-provisioned and injected as DATABASE_URL. Verified on Spring Boot: a jobs table with a state and attempts counter, processing inside a row-locked transaction, and a second run that is a no-op (job=done attempts=1 idempotent=true). Not separately tested: your job types, payload schema and retry policy; treat the mobile backend-specific behavior as your application code.

Representational Queries

• Host mobile backend with Spring Boot: Postgres-backed state
• Where can I host Mobile backend built with Spring Boot?
• I need a durable state schema and retry/recovery semantics implemented by application code.

Resource Requirements

• primitive:compute
• primitive:postgres

Infrastructure Requirements

Compute

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

Postgres

• Label: Postgres
• Status: verified
• Summary: Managed PostgreSQL 16 runs in its own microVM and is auto-provisioned when an app needs a database and no DATABASE_URL is supplied.

Prerequisites

• A Spring Boot project that builds and starts with the documented commands (./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)
• A PostgreSQL driver reading DATABASE_URL at runtime (auto-provisioned when omitted, or supplied with --env)
• An Ample account token with servers:write, databases:read

Workflow 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. Implement the pattern on PostgreSQL:
   The fixture's module implements durable job state: a jobs table with a state and attempts counter, processing inside a row-locked transaction, and a second run that is a no-op (job=done attempts=1 idempotent=true). Copy the approach into your schema; keep migrations idempotent and run them with --release-command.

3. Deploy:
   Run the synchronous deploy once and read the result (exit 0 live, 1 failed, 2 blocked). Re-running with no change is a no-op. Command: ample deploy . --name --public

4. Verify:
   Fetch the live URL and the pattern self-test route(s) (/p/durable-job-state) from the example; then run your own checks. On failure read ample logs --kind build then --kind runtime.
   Command: ample logs --kind build

Success Checks

• App responds on its public URL
  • Kind: http_get
  • Path: /
  • Expect: ample canary spring boot patterns
• Durable-job-state self-test
  • Kind: http_get
  • Path: /p/durable-job-state
  • Expect: job=done attempts=1 idempotent=true

Examples

• Title: Spring Boot pattern fixture
  Description: Multi-pattern Spring Boot app whose durable job state module was checked live; the module is under tests/deploy-canaries/_pattern-modules.
  Source Ref: tests/deploy-canaries/spring-boot-patterns

Limitations

• Verified on the jvm-21 template at s-1vcpu-2gb with the example fixture; other sizes, templates and Spring Boot major versions are not verified.
• The mobile backend itself (your job types, payload schema and retry policy) is application code and was not separately tested; the pattern checks are what was verified.
• 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.
• Managed PostgreSQL 16 only; extensions, connection limits and backup or restore procedures are not verified; apps and their databases are placed together.

Cost Estimate

• Currency: USD
• Monthly Amount: 10.0
• Basis: size prices from pricing.toml (loaded by the API) at build revision 1ac5595375130d45290090e82ed0f554ccd45405-dirty
• Components:
  • App server, size: s-1vcpu-1gb, quantity: 1.0, monthlyAmount: 5.0
  • Managed PostgreSQL database, size: s-1vcpu-1gb, quantity: 1.0, monthlyAmount: 5.0
• Note: Always-on monthly price of the tested sizes; apps and databases auto-pause when idle. Buckets are allocation-priced per quota and not included.

Evidence Summary

• Kind: canary_run
  Summary: Spring Boot pattern fixture deployed on Ample; checks passed for durable-job-state and configuration-secrets. Pattern proof: a jobs table with a state and attempts counter, processing inside a row-locked transaction, and a second run that is a no-op (job=done attempts=1 idempotent=true).
  Observed At: 2026-09-21T02:34:39Z
  Implementation Revision: 1d28ae0-dirty (CLI 0.1.21)
  Expires At: 2027-03-20T02:34:39Z

Next Actions

• Action ID: browse-catalog
  Label: Browse the catalog index
  Method: GET
  Relative Path: /v1/catalog

• Action ID: search-recipes
  Label: Search published recipes by intent, stack and constraints
  Method: POST
  Relative Path: /v1/catalog/search
  Parameters: {"body":{"limit":5,"query":"Host mobile backend with Spring Boot: Postgres-backed state"}}

• Action ID: plan:page:recipes:mobile-backend:spring-boot:persistent-state
  Label: Prepare a side-effect-free deployment plan for an authorized project
  Method: POST
  Relative Path: /v1/catalog/plan
  Parameters: {"body":{"inputs":{},"projectId":"","recipeId":"page:recipes:mobile-backend:spring-boot:persistent-state","recipeRevision":"r1"}}

• Action ID: auth-setup
  Label: Read the existing agent authentication setup
  Method: GET
  Relative Path: /mcp/setup

• Action ID: browse:workload:mobile-backend
  Label: Browse Mobile backend
  Method: GET
  Relative Path: /v1/catalog/nodes/workload%3Amobile-backend

• Action ID: browse:stack:framework-spring-boot
  Label: Browse Spring Boot
  Method: GET
  Relative Path: /v1/catalog/nodes/stack%3Aframework-spring-boot

• Action ID: browse:pattern:durable-job-state
  Label: Browse Durable job state
  Method: GET
  Relative Path: /v1/catalog/nodes/pattern%3Adurable-job-state

• Action ID: browse:intent:deploy-api
  Label: Browse Deploy API
  Method: GET
  Relative Path: /v1/catalog/nodes/intent%3Adeploy-api