## Host ai workflow runner with NestJS: stored input and output artifacts

### Summary
Deploy an ai workflow runner built with NestJS 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. Verified on NestJS: 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). Not separately tested: your export formats, retention policy and entitlement model; treat the ai workflow runner-specific behavior as your application code.

### Representative Queries
- Host ai workflow runner with NestJS: stored input and output artifacts
- Where can I host AI workflow runner built with NestJS?
- I need an input/output artifact contract, object metadata and access boundaries.

### Resource Requirements
- primitive:compute
- primitive:postgres
- primitive:s3-compatible-object-storage

### 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.

- **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.

- **S3-compatible object storage**: Buckets are S3-compatible with issued credentials; PutObject and GetObject are verified by canary. Other S3 operations are not verified.

### Framework
NestJS

### Workload
AI workflow runner

### Release Status
Published

### Support Status
Verified

### Execution Status
Ready

### Prerequisites
- A NestJS project that builds and starts with the documented commands (npm install, nest build (TypeScript) then node dist/main.js on the node-22 template)
- 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

### Tested Configuration
- **Template**: node-22
- **Runtime**: node
- **Size**: s-1vcpu-1gb
- **Install**: npm install
- **Build**: npm run build --if-present
- **Start**: npm run start

### Input Schema
```json
{
  "type": "object",
  "additionalProperties": false,
  "required": ["env", "name", "path"],
  "properties": {
    "env": {
      "type": "array",
      "maxItems": 50,
      "items": {
        "type": "string",
        "pattern": "^[A-Z][A-Z0-9_]*=.*$"
      },
      "description": "Encrypted environment variables (bucket credentials, secrets)"
    },
    "name": {
      "type": "string",
      "maxLength": 63,
      "minLength": 1,
      "pattern": "^[a-z0-9-]+$",
      "description": "App name"
    },
    "path": {
      "type": "string",
      "maxLength": 512,
      "minLength": 1,
      "description": "Project directory or ample.toml service"
    },
    "release_command": {
      "type": "string",
      "maxLength": 512,
      "description": "Migration command run before activation"
    }
  }
}
```

### Workflow Steps
1. **Build and start**: npm install, nest build (TypeScript) then node dist/main.js on the node-22 template. 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 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.  Command: `ample deploy . --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 --kind build` then `--kind runtime`. Command: `ample logs --kind build`

### Examples
- **Title**: NestJS pattern fixture
  **Description**: Multi-pattern NestJS app whose generated downloads module was checked live; the module is under tests/deploy-canaries/_pattern-modules.
  **Source Ref**: tests/deploy-canaries/nestjs-patterns

### Success Checks
- **App responds on its public URL**: Kind: `http_get`, Path: `/`, Expect: `ample canary nestjs patterns`.
- **Generated-downloads self-test**: Kind: `http_get`, Path: `/p/generated-downloads`, Expect: `export=ok rows=3 (with ?token=...; 401 without)`.

### Limitations
- Verified on the node-22 template at s-1vcpu-1gb with the example fixture; other sizes, templates and NestJS major versions are not verified.
- The ai workflow runner itself (your export formats, retention policy and entitlement model) 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.
- PutObject and GetObject with path-style addressing are verified; multipart upload, listing, presigned URLs and lifecycle rules are not.

### Cost Estimate
- **Currency**: USD
- **Monthly Amount**: 10.0
- **Authoritative**: true
- **Basis**: size prices from pricing.toml (loaded by the API) at build revision 1ac5595375130d45290090e82ed0f554ccd45405-dirty
- **Components**:
  - Name: app server, Size: s-1vcpu-1gb, Quantity: 1.0, Monthly Amount: 5.0
  - Name: managed PostgreSQL database, Size: s-1vcpu-1gb, Quantity: 1.0, Monthly 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
- **Kind**: canary_run
  **Summary**: NestJS pattern fixture deployed on Ample (npm install, nest build (TypeScript) then node dist/main.js on the node-22 template); 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).
  **Observed At**: 2026-09-21T02:34:39Z
  **Implementation Revision**: 1d28ae0-dirty (CLI 0.1.21)
  **Expires At**: 2027-03-20T02:34:39Z
- **Kind**: canary_run
  **Summary**: The same NestJS app deployed with a --release-command migration; the marker it created was readable after activation.
  **Observed At**: 2026-09-20T02:16:51Z
  **Implementation Revision**: 199ff1dfd52683832ae75d3f98b53a7a4bff7f96-dirty (CLI e3181f5)
  **Expires At**: 2027-03-19T02:16:51Z

### Last Verified At
2026-09-21T02:34:39Z