### Host AI Workflow Runner with Echo: Worker Execution and Job State

#### Summary
Deploy an AI workflow runner built with Echo as a public web service plus a dedicated worker process on Ample. `ample plan --write` discovers both services and their shared database and writes ample.toml; `ample up` reconciles the topology: a managed PostgreSQL 16 database, a public web microVM and a private worker microVM (kind worker, no public URL), both reading DATABASE_URL. Verified on Echo: a separately deployed worker service (kind worker, no public URL) sharing a declared managed PostgreSQL database with the web service, consuming a jobs table with row locks and marking jobs done once (worker=done attempts=1). Not separately tested: your job payloads, retry policy and scheduling; treat the AI workflow runner-specific behavior as your application code.

#### Main Content
##### Representative Queries
- Host AI workflow runner with Echo: worker execution and job state
- Where can I host AI workflow runner built with Echo?
- I need a separately runnable worker, durable job records and idempotent retries; not a managed queue.

##### 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.
- **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.

##### Prerequisites
- A repository with the web app and the worker as separate service directories (the fixture uses apps/web and apps/worker), each building and starting with the documented commands (CGO_ENABLED=0 go build -o app ./... then ./app on the ubuntu-24.04 template (go.sum committed for a reproducible build); the worker starts with ./worker and binds no port).
- Both services read DATABASE_URL at runtime and share one jobs table; the worker claims rows with SELECT ... FOR UPDATE SKIP LOCKED and marks them done once.
- An Ample account token with servers:write and databases:write (ample up creates the database).

##### Workflow Steps
1. **Plan the topology**: Run the planner once. It discovers the web and worker services, infers kind = "worker" for the process without a port, declares the database each service needs, and writes ample.toml. Exit 2 means it left questions in the manifest; answer them with --answer or by editing the file.
   - Command: `ample plan --write .`

2. **Share one database**: Keep a single [databases.main] with engine = "postgres", drop any per-service database the planner added, and set DATABASE_URL = { database = "main" } under both [services.web.env] and [services.worker.env].
   - Command: `ample plan --offline .`

3. **Apply**: Reconcile the whole manifest in dependency order: the database first, then both services. It is idempotent and never destructive; exit 0 means everything applied, 2 needs input, 1 a failed resource (independent siblings still proceed and re-running resumes).
   - Command: `ample up .`

4. **Verify**: Fetch the web service URL and its worker status route (/p/worker-queue/status in the example) and confirm the worker processed the enqueued job; on failure read the worker service's runtime logs.
   - Command: `ample logs  --kind runtime`

##### Examples
- **Echo web + worker fixture**: A Echo web app (apps/web) and a worker process (apps/worker) sharing one managed PostgreSQL database; the queue module is under tests/deploy-canaries/_pattern-modules.
  
#### Success Checks
- Web service responds on its public URL.
  - Kind: http_get
  - Path: /
  - Expect: ample canary echo patterns

- Worker consumed the enqueued job.
  - Kind: http_get
  - Path: /p/worker-queue/status
  - Expect: worker=done attempts=1 result=processed-by-worker

##### Limitations
- Verified on the ubuntu-24.04 template at s-1vcpu-1gb for both services with the example fixture; other sizes, templates and Echo major versions are not verified.
- The AI workflow runner itself (your job payloads, retry policy and scheduling) is application code and was not separately tested; the worker-queue check is what was verified.
- The worker is a single long-running process supervised in its own microVM; there is no scheduler, cron or horizontal worker scaling in this recipe, and the check ran immediately after deploy so idle behavior of the worker VM is not verified.
- Managed PostgreSQL 16 only; extensions, connection limits and backup or restore procedures are not verified; apps and their databases are placed together.
- Region, compliance attestations and request-duration limits are unknown and not claimed.

##### Cost Estimate
- **Currency**: USD
- **Monthly Amount**: 15.0
- **Basis**: Size prices from pricing.toml (loaded by the API) at build revision 1ac5595375130d45290090e82ed0f554ccd45405-dirty
- **Components**:
  - Web server: size=s-1vcpu-1gb, quantity=1.0, monthlyAmount=5.0
  - Worker server: size=s-1vcpu-1gb, quantity=1.0, monthlyAmount=5.0
  - Managed PostgreSQL database: size=s-1vcpu-1gb, quantity=1.0, monthlyAmount=5.0
  - Note: Always-on monthly price of the tested sizes for the web service, the worker service and the database; apps auto-pause when idle.

##### Evidence Summary
- **Kind**: canary_run
  - **Summary**: Echo web service plus a separate Echo worker process deployed on Ample with `ample plan --write` then `ample up` (CGO_ENABLED=0 go build -o app ./... then ./app on the ubuntu-24.04 template (go.sum committed for a reproducible build)); the web service enqueued a job that the private worker service consumed from the shared managed PostgreSQL database.
  - **Observed At**: 2026-09-20T03:56:46Z
  - **Implementation Revision**: 03b6402b1b3e19178985f08ea4033804521d85d4-dirty (CLI b75e104)
  - **Expires At**: 2027-03-19T03:56:46Z
  - **Scope**: 
    - Checks: ["/","/p/worker-queue/status"]
    - Pattern: pattern:dedicated-worker-process
    - Services: ["web","worker"]
    - Template: ubuntu-24.04
    - Tool: ample_up

##### Last Verified At
2026-09-20T03:56:46Z

##### Unknowns
- Region availability is unknown until a verified region fact is recorded.
- Compliance attestations are unknown; none are claimed.

##### Formats
- [HTML](/content/recipes/ai-workflow-runner/echo/worker-state/index.html)
- [Markdown](/content/recipes/ai-workflow-runner/echo/worker-state.md)
- [JSON](https://api.ample.computer/v1/catalog/recipes/page%3Arecipes%3Aai-workflow-runner%3Aecho%3Aworker-state)

##### Next Actions
- **Browse the catalog index**: 
  - Operation: catalog_index
  - Method: GET
  - Relative Path: /v1/catalog.

- **Search published recipes by intent, stack and constraints**: 
  - Operation: search_recipes
  - Method: POST
  - Relative Path: /v1/catalog/search
  - Parameters: {"body":{"limit":5,"query":"Host ai workflow runner with Echo: worker execution and job state"}}

- **Prepare a side-effect-free deployment plan for an authorized project**: 
  - Operation: plan_deployment
  - Method: POST
  - Relative Path: /v1/catalog/plan
  - Parameters: {"body":{"inputs":{},"projectId":"","recipeId":"page:recipes:ai-workflow-runner:echo:worker-state","recipeRevision":"r1"}}

- **Read the existing agent authentication setup**: 
  - Operation: existing_auth_setup
  - Method: GET
  - Relative Path: /mcp/setup

- **Browse AI workflow runner**: 
  - Operation: browse_node 
  - Method: GET  
  - Relative Path: /v1/catalog/nodes/workload%3Aai-workflow-runner.

- **Browse Echo**: 
  - Operation: browse_node 
  - Method: GET
  - Relative Path: /v1/catalog/nodes/stack%3Aframework-echo.

- **Browse Dedicated worker process**: 
  - Operation: browse_node 
  - Method: GET
  - Relative Path: /v1/catalog/nodes/pattern%3Adedicated-worker-process.

- **Browse Deploy AI app**: 
  - Operation: browse_node 
  - Method: GET
  - Relative Path: /v1/catalog/nodes/intent%3Adeploy-ai-app.