### Host subscription content with Phoenix: relational catalog data

Deploy a subscription content built with Phoenix on Ample using the transactional workflows 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 Phoenix: 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). Not separately tested: your domain records, validation rules and concurrency policy; treat the subscription content-specific behavior as your application code.

#### Representative Queries
- Host subscription content with Phoenix: relational catalog data
- Where can I host Subscription content built with Phoenix?
- I need catalog tables, transactional update logic and application-level access boundaries.

#### Resource Requirements
- **Compute**
- **Postgres**

#### Infrastructure 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. (Status: verified)
- **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. (Status: verified)

#### Workflow Steps
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 transactional workflows: 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). 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/transactional-workflows) from the example; then run your own checks. On failure read `ample logs  --kind build` then `--kind runtime`.  
   Command: `ample logs  --kind build`

#### Limitations
- Verified on the elixir-1.18 template at s-1vcpu-1gb with the example fixture; other sizes, templates and Phoenix major versions are not verified.
- The subscription content itself (your domain records, validation rules and concurrency 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**: s-1vcpu-1gb, Quantity: 1.0, Monthly Amount: 5.0
- **Managed PostgreSQL database**: s-1vcpu-1gb, Quantity: 1.0, Monthly Amount: 5.0

#### Examples
- **Phoenix pattern fixture**  
  Multi-pattern Phoenix app whose transactional workflows module was checked live; the module is under tests/deploy-canaries/_pattern-modules.  
  Source Reference: tests/deploy-canaries/phoenix-patterns

#### Next Actions
- **Browse the catalog index**  
  Action ID: browse-catalog, Method: GET, Relative Path: /v1/catalog
- **Search published recipes by intent, stack and constraints**  
  Action ID: search-recipes, Method: POST, Relative Path: /v1/catalog/search  
  Parameters: {"body":{"limit":5,"query":"Host subscription content with Phoenix: relational catalog data"}}
- **Prepare a side-effect-free deployment plan for an authorized project**  
  Action ID: plan:page:recipes:subscription-content:phoenix:relational-catalog, Method: POST, Relative Path: /v1/catalog/plan  
  Parameters: {"body":{"inputs":{},"projectId":"","recipeId":"page:recipes:subscription-content:phoenix:relational-catalog","recipeRevision":"r1"}}