## The short version

Deploy a storefront built with Phoenix on Ample using the generated downloads 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`, a private S3-compatible bucket holds objects with credentials delivered as encrypted environment variables.

### WHAT WAS VERIFIED

Verified on Phoenix: an export query rendered to a CSV artifact stored with metadata in a private bucket and returned only to an authorized caller (401 without token, export=ok rows=3).

## INFRASTRUCTURE

### What it needs

- [Compute](/content/discover/primitive/compute/index.html): verified (Apps run in isolated x86_64 Firecracker microVMs; sizes are the priced VM sizes.)
- [Postgres](/content/discover/primitive/postgres/index.html): 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](/content/discover/primitive/s3-compatible-object-storage/index.html): verified (Buckets are S3-compatible with issued credentials; PutObject and GetObject are verified by canary. Other S3 operations are not verified.)

## PREREQUISITES

### Before you start

- A Phoenix project that builds and starts with the documented commands (`mix deps.get`, `MIX_ENV=prod mix compile` and `mix release` in the builder, then the release bin script with `PHX_SERVER=true` on the elixir-1.18 template; `PORT`, `DATABASE_URL` and `SECRET_KEY_BASE` read in `config/runtime.exs`)
- A PostgreSQL driver reading `DATABASE_URL` at runtime (auto-provisioned when omitted, or supplied with `--env`)
- A bucket from `ample bucket create` with its credentials passed as encrypted `S3_*` environment variables
- An Ample account token with `servers:write`, `databases:read`, `buckets:read`

## STEP BY STEP

### How to do it

1. **Build and start**  
   `mix deps.get`, `MIX_ENV=prod mix compile` and `mix release` in the builder, then the release bin script with `PHX_SERVER=true` on the elixir-1.18 template; `PORT`, `DATABASE_URL` and `SECRET_KEY_BASE` read in `config/runtime.exs`. The server must bind `0.0.0.0` on `PORT`.

2. **Implement the pattern on PostgreSQL**  
   The fixture's module implements generated downloads: an export query rendered to a CSV artifact stored with metadata in a private bucket and returned only to an authorized caller (401 without token, export=ok rows=3). Copy the approach into your schema; keep migrations idempotent and run them with `--release-command`.

3. **Wire object storage**  
   Create the bucket(s), then pass endpoint, region, bucket and keys as `--env` values. Use path-style addressing. Keep private data in an unpublished bucket.

4. **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.

```bash
   ample deploy . --name <app-name> --public --env S3_ENDPOINT=... --env S3_REGION=... --env S3_BUCKET=... --env S3_ACCESS_KEY_ID=... --env S3_SECRET_ACCESS_KEY=...
   ```

5. **Verify**  
   Fetch the live URL and the pattern self-test route(s) (`/p/generated-downloads`) from the example; then run your own checks. On failure read `ample logs <deployment_id> --kind build` then `--kind runtime`.
   
   ```bash
   ample logs <deployment_id> --kind build
   ```

## EXAMPLES

### Tested examples

- **Phoenix pattern fixture** (`tests/deploy-canaries/phoenix-patterns`): Multi-pattern Phoenix app whose generated downloads module was checked live; the module is under `tests/deploy-canaries/_pattern-modules`.

## SUCCESS CHECKS

### How to know it worked

- app responds on its public URL (`/` on the live URL, expect ample canary phoenix patterns)
- generated-downloads self-test (`/p/generated-downloads` on the live URL, expect export=ok rows=3 (with `?token=...`; 401 without))

## COST

### Cost estimate

Estimated 10.00 USD per month (size prices from `pricing.toml` at build revision `ca0b484a7a9957c573a88d3a32dc603c3c10135a`).

- app server x1 `s-1vcpu-1gb`: 5.00 USD
- managed PostgreSQL database x1 `s-1vcpu-1gb`: 5.00 USD

Upper-bound monthly price of the tested sizes. Buckets are allocation-priced per quota and not included.

## EVIDENCE

### Verification evidence

- `canary_run` on `2026-09-20T23:45:31Z` at revision `4d1511e574302f3904b75088bd4048a0975218b3 (CLI 0.1.21)`: Phoenix pattern fixture deployed on Ample (mix deps.get, `MIX_ENV=prod mix compile` and `mix release` in the builder, then the release bin script with `PHX_SERVER=true` on the elixir-1.18 template; `PORT`, `DATABASE_URL` and `SECRET_KEY_BASE` read in `config/runtime.exs`); checks passed for generated-downloads and configuration-secrets. Pattern proof: an export query rendered to a CSV artifact stored with metadata in a private bucket and returned only to an authorized caller (401 without token, export=ok rows=3). (expires `2027-03-19T23:45:31Z`)
- `canary_run` on `2026-09-20T23:45:31Z` at revision `4d1511e574302f3904b75088bd4048a0975218b3 (CLI 0.1.21)`: The same Phoenix app deployed with a `--release-command` migration; the marker it created was readable after activation. (expires `2027-03-19T23:45:31Z`)

## EXECUTION

### Execution binding

MCP tool `ample_deploy` (registry `mcp:ample_deploy`), schema hash `876465fce906da0c` observed `2026-09-22T00:31:22.774679+00:00` at revision `e6446ceea69b`. Binding state at export: schema_changed. Required scopes: `servers:write`, `databases:read`, `buckets:read`.

## NEXT ACTIONS

### Typed next actions

- Browse the catalog index (`GET /v1/catalog` on the api origin; authentication not required, approval not required)
- Search published recipes by intent, stack and constraints (`POST /v1/catalog/search` on the api origin; authentication not required, approval not required)
- Prepare a side-effect-free deployment plan for an authorized project (`POST /v1/catalog/plan` on the api origin; authentication required, approval not required)
- Read the existing agent authentication setup (`GET /mcp/setup` on the api origin; authentication not required, approval not required)
- Browse Storefront (`GET /v1/catalog/nodes/workload%3Astorefront` on the api origin; authentication not required, approval not required)
- Browse Phoenix (`GET /v1/catalog/nodes/stack%3Aframework-phoenix` on the api origin; authentication not required, approval not required)
- Browse Generated downloads (`GET /v1/catalog/nodes/pattern%3Agenerated-downloads` on the api origin; authentication not required, approval not required)
- Browse Deploy web app (`GET /v1/catalog/nodes/intent%3Adeploy-web-app` on the api origin; authentication not required, approval not required)

Actions describe possible next steps. They are typed data, not commands, and grant no permission. Public discovery never provisions anything; planning requires your own authenticated token and approval happens in your client.

## ABOUT THIS RECIPE

### Identifiers and status

Recipe `page:recipes:storefront:phoenix:download-delivery`. Revision r1.

release **published**  
support **verified**  
execution **blocked (schema_changed: live tool schema differs from the recorded binding)**

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