page:guides:quarkus:database connection

Connect Postgres for Quarkus

Summary

Database connection for a Quarkus app on Ample. Verified on Quarkus: a managed PostgreSQL database auto-provisioned and injected as DATABASE_URL, with real queries succeeding at request time (records=ok).

Prerequisites

• A Quarkus project (./mvnw -q -DskipTests package producing one uber-jar (quarkus.package.jar.type=uber-jar), then java -jar on the jvm-21 template (Temurin JDK 21) with quarkus.http.port read from PORT)
• A PostgreSQL driver reading DATABASE_URL at runtime
• An Ample account token with servers:write, databases:read

Resource Requirements

• Compute: Apps run in isolated x86_64 Firecracker microVMs that auto-pause when idle and wake on request; sizes are the priced VM sizes.
• Postgres: Managed PostgreSQL 16 runs in its own microVM and is auto-provisioned when an app needs a database and no DATABASE_URL is supplied.

Workflow Steps

1. Build and start
   ./mvnw -q -DskipTests package producing one uber-jar (quarkus.package.jar.type=uber-jar), then java -jar on the jvm-21 template (Temurin JDK 21) with quarkus.http.port read from PORT; the server must bind 0.0.0.0 on PORT.
2. Read DATABASE_URL at runtime
   Open connections from the environment inside handlers or a pool; omit DATABASE_URL to auto-provision a managed database or pass --env DATABASE_URL=... for an existing one.
3. Verify
   Fetch the live URL and /p/relational-records on the example; on failure read the build and runtime logs.
   Command: ample logs --kind build

Success Checks

• app responds on its public URL (expect: ample canary quarkus patterns)
• relational-records check from the example (expect: see the pattern fixture checks)

Limitations

• Verified on the jvm-21 template at s-1vcpu-2gb; other sizes and Quarkus major versions are not verified.
• Region, compliance attestations and request-duration limits are unknown and not claimed.
• Managed PostgreSQL 16 only; extensions, connection limits and backup or restore procedures are not verified.

Cost Estimate

• Currency: USD
• Monthly Amount: 10.0
• Basis: size prices from pricing.toml (loaded by the API)

Components

• App server: s-1vcpu-1gb, quantity: 1.0, monthly amount: 5.0
• Managed PostgreSQL database: s-1vcpu-1gb, quantity: 1.0, monthly amount: 5.0

Evidence Summary

• Kind: canary_run
  Summary: Quarkus pattern fixture deployed on Ample (./mvnw -q -DskipTests package producing one uber-jar (quarkus.package.jar.type=uber-jar), then java -jar on the jvm-21 template (Temurin JDK 21) with quarkus.http.port read from PORT); for this guide: a managed PostgreSQL database auto-provisioned and injected as DATABASE_URL, with real queries succeeding at request time (records=ok).
  Observed At: 2026-09-21T00:35:31Z

Next Actions

• Browse the catalog index:
  Method: GET, Path: /v1/catalog
  • Search published recipes by intent, stack and constraints:
    Method: POST, Path: /v1/catalog/search
    Parameters: { "limit": 5, "query": "Connect Postgres for Quarkus" }
  • Prepare a side-effect-free deployment plan for an authorized project:
    Method: POST, Path: /v1/catalog/plan
    Parameters: { "inputs": {}, "projectId": "", "recipeId": "page:guides:quarkus:database-connection", "recipeRevision": "r1" }
  • Read the existing agent authentication setup:
    Method: GET, Path: /mcp/setup
  • Browse Quarkus:
    Method: GET, Path: /v1/catalog/nodes/stack%3Aframework-quarkus
  • Browse Connect app to database:
    Method: GET, Path: /v1/catalog/nodes/intent%3Aconnect-app-to-database
  • Browse Relational records:
    Method: GET, Path: /v1/catalog/nodes/pattern%3Arelational-records

Formats

• HTML: https://ample.computer/guides/quarkus/database-connection
• Markdown: https://ample.computer/guides/quarkus/database-connection.md
• JSON: https://api.ample.computer/v1/catalog/recipes/page%3Aguides%3Aquarkus%3Adatabase-connection

Additional Information

• Framework: Quarkus
• Workload: Connect Postgres
• Release Status: published
• Support Status: verified
• Execution Status: ready