django.md
Home services: order tracking using Django
Summary
A order tracking blueprint for home services built with Django on Ample. Domain schema: services (sku, name, category, price_from, duration_estimate): service catalog as SKUs; parts_stock (sku, delta, reason, moved_at): parts and consumables movements; jobs (job_no, service_area, status, scheduled_for): jobs as orders with status transitions; job_lines (job_no, sku, qty): services and parts on a job; events (seq, record_type, record_id, kind, at): application-owned history written in the same transaction. Public information: service catalog and pricing from, service areas and hours, licensing and insurance summary. Kept out of scope until handling is reviewed: customer addresses and access notes, payment details. Customer addresses and access instructions are personal data; keep them out until handling is reviewed. Technical basis verified on Django: an optimistic version check and an event row written in the same transaction, a stale update rejected, and a history query over the application-owned events (history=2 conflict=rejected).
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.)
- Postgres: verified (Managed PostgreSQL 16 runs in its own microVM and is auto-provisioned when an app needs a database and no DATABASE_URL is supplied.)
- S3-compatible object storage: verified (Buckets are S3-compatible with issued credentials; PutObject and GetObject are verified by canary. Other S3 operations are not verified.)
Prerequisites
- A Django project (pip install into .ample/python from requirements.txt, then waitress serving project.wsgi from run.py reading PORT on the python-3.12 template)
- A PostgreSQL driver reading DATABASE_URL (auto-provisioned when omitted)
- Bucket credentials from
ample bucket createpassed as encrypted S3_* environment variables - A review of which home services data classes may be handled at all; this blueprint models public information only
Exact 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 run.py
Steps
- Model the home services domain. Create the tables services, parts_stock, jobs, job_lines, events. Service catalog as skus lives in services; keep the sensitive classes (customer addresses and access notes, payment details) out of this schema.
- Workflow step 1. Model orders with explicit status transitions and order lines
- Workflow step 2. Apply status changes transactionally and record an event per change
- Workflow step 3. Expose status history to authorized callers only
- Workflow step 4. Deploy and verify history and conflict rejection
- Deploy. Run the synchronous deploy once and read the result. Re-running with no change is a no-op.
ample deploy . --name <app-name> --public --start "python3 run.py" --env S3_ENDPOINT=... --env S3_REGION=... --env S3_BUCKET=... --env S3_ACCESS_KEY_ID=... --env S3_SECRET_ACCESS_KEY=...
- Verify. Run the pattern self-test(s) from the example (/p/transactional-workflows) and your own acceptance checks for the home services workflow.
ample logs <deployment_id> --kind build
Tested examples
- Django pattern fixture (tests/deploy-canaries/django-patterns): Verified transactional workflows basis for this blueprint.
Success checks
- app responds on its public URL (
/on the live URL, expect ample canary django patterns) - transactional-workflows self-test from the example (
/p/transactional-workflowson the live URL, expect see the pattern fixture checks)
Limitations
- The technical basis (transactional workflows on Django) was verified with the pattern fixture; the home services schema and workflow are an original design for this blueprint and were not executed as a separate application.
- No health, financial, privacy or other compliance claim is made. Customer addresses and access instructions are personal data; keep them out until handling is reviewed.
- Public content and synthetic examples only until actual data-handling requirements have been reviewed.
- Verified on the python-3.12 template at s-1vcpu-1gb; region, request-duration limits and other sizes are unknown or unverified.
- Managed PostgreSQL 16 only; extensions, connection limits and backup or restore procedures are not verified.
- PutObject and GetObject with path-style addressing are verified; other S3 operations and CDN cache rules are not.
Cost estimate
Estimated 10.00 USD per month (size prices from pricing.toml at build revision a1b8c38919e59cd035ebabaced73cf84ece24371).
- app server x1
s-1vcpu-1gb: 5.00 USD - managed PostgreSQL database x1
s-1vcpu-1gb: 5.00 USD
Always-on monthly price of the tested sizes; apps and databases auto-pause when idle. Buckets are allocation-priced per quota and not included.
Verification evidence
- canary_run on 2026-09-20T03:31:44Z at revision
03b6402b1b3e19178985f08ea4033804521d85d4-dirty (CLI b75e104): Django pattern fixture deployed on Ample (pip install into .ample/python from requirements.txt, then waitress serving project.wsgi from run.py reading PORT on the python-3.12 template); the transactional workflows checks passed: an optimistic version check and an event row written in the same transaction, a stale update rejected, and a history query over the application-owned events (history=2 conflict=rejected). The blueprint's Home services schema and workflow below build on that verified basis and were not separately executed. (expires 2027-03-19T03:31:44Z)
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, databases:read, buckets:read.