# Host ai workflow runner with Echo: Postgres-backed state

## Summary
Deploy a ai workflow runner built with Echo on Ample using the durable job state 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 Echo: a jobs table with a state and attempts counter, processing inside a row-locked transaction, and a second run that is a no-op (job=done attempts=1 idempotent=true). Not separately tested: your job types, payload schema and retry policy; treat the ai workflow runner-specific behavior as your application code.

## Representative Queries
- Host ai workflow runner with Echo: Postgres-backed state
- Where can I host AI workflow runner built with Echo?
- I need a durable state schema and retry/recovery semantics implemented by application code.

## Resource Requirements
- primitive:compute
- primitive:postgres

## Infrastructure Requirements
### Compute
- **Status**: Verified  
- **Summary**: Apps run in isolated x86_64 Firecracker microVMs that auto-pause when idle and wake on request; sizes are the priced VM sizes.

### Postgres
- **Status**: Verified  
- **Summary**: 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 Echo project that builds and starts 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))
- A PostgreSQL driver reading DATABASE_URL at runtime (auto-provisioned when omitted, or supplied with --env)
- An Ample account token with servers:write, databases:read

## Tested Configuration
- **Template**: ubuntu-24.04  
- **Runtime**: go  
- **Size**: s-1vcpu-1gb  
- **Build Command**: CGO_ENABLED=0 go build -o app ./...  
- **Start Command**: ./app

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

## Workflow Steps
1. **Build and start**  
   CGO_ENABLED=0 go build -o app ./... then ./app on the ubuntu-24.04 template (go.sum committed for a reproducible build). The server must bind 0.0.0.0 on PORT.  
2. **Implement the pattern on PostgreSQL**  
   The fixture's module implements durable job state: a jobs table with a state and attempts counter, processing inside a row-locked transaction, and a second run that is a no-op (job=done attempts=1 idempotent=true). 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/durable-job-state) from the example; then run your own checks. On failure read `ample logs --kind build` then `--kind runtime`.  
   Command: ample logs --kind build

## Success Checks
- **App responds on its public URL**  
  - **Kind**: http_get  
  - **Path**: /  
  - **Expect**: ample canary echo patterns  
- **Durable-job-state self-test**  
  - **Kind**: http_get  
  - **Path**: /p/durable-job-state  
  - **Expect**: job=done attempts=1 idempotent=true

## Limitations
- Verified on the ubuntu-24.04 template at s-1vcpu-1gb with the example fixture; other sizes, templates and Echo major versions are not verified.
- The ai workflow runner itself (your job types, payload schema and retry 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**:  
  - **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**: Echo pattern fixture deployed on Ample; checks passed for durable-job-state and configuration-secrets.  
  - **Observed At**: 2026-09-21T02:34:39Z  
- **Kind**: canary_run  
  - **Summary**: The same Echo app deployed with a --release-command migration; the marker it created was readable after activation.  
  - **Observed At**: 2026-09-20T02:43:30Z

## Formats
- **HTML**: https://ample.computer/recipes/ai-workflow-runner/echo/persistent-state  
- **Markdown**: https://ample.computer/recipes/ai-workflow-runner/echo/persistent-state.md  
- **JSON**: https://api.ample.computer/v1/catalog/recipes/page%3Arecipes%3Aai-workflow-runner%3Aecho%3Apersistent-state

## Next Actions
- **Browse the catalog index**  
- **Search published recipes by intent, stack and constraints**  
- **Prepare a side-effect-free deployment plan for an authorized project**  
- **Read the existing agent authentication setup**  
- **Browse AI workflow runner**  
- **Browse Echo**  
- **Browse Durable job state**  
- **Browse Deploy AI app**