page:recipes:graphql api:flask:persistent state

Host GraphQL API with Flask: Postgres-backed state

Deploy a GraphQL API built with Flask 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 Flask: 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 GraphQL API-specific behavior as your application code.

Representative Queries

• Host GraphQL API with Flask: Postgres-backed state
• Where can I host GraphQL API built with Flask?
• I need a durable state schema and retry/recovery semantics implemented by application code.

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.

Framework

Flask
Workload: GraphQL API
Release Status: published
Support Status: verified
Execution Status: ready

Prerequisites

• A Flask project that builds and starts with the documented commands (pip install into .ample/python from requirements.txt, then waitress from app.py reading PORT on the python-3.12 template)
• 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

Tested Configuration

• Template: python-3.12
• Runtime: python
• Size: s-1vcpu-1gb
• Install: python3 -m pip install --target .ample/python -r requirements.txt
• Start: PYTHONPATH=.ample/python:${PYTHONPATH:-} python3 app.py

Workflow Steps

1. Build and start
   pip install into .ample/python from requirements.txt, then waitress from app.py reading PORT on the python-3.12 template. 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.
   ample deploy . --name --public --start "python3 app.py"
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.
   ample logs --kind build

Limitations

• Verified on the python-3.12 template at s-1vcpu-1gb with the example fixture; other sizes, templates and Flask major versions are not verified.
• The GraphQL API 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

Monthly Amount: 10.0 USD
Components:

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

• Canary Run: Flask pattern fixture deployed on Ample; checks passed for durable-job-state and configuration-secrets.
• Observed At: 2026-09-21T01:14:18Z

Next Actions

• Browse the catalog index
• Search published recipes by intent, stack and constraints
• Prepare a side-effect-free deployment plan for an authorized project
• Read the existing agent authentication setup
• Browse GraphQL API
• Browse Flask
• Browse Durable job state
• Browse Deploy API

For more detailed documentation and insights, visit the official documentation.