### Host AI Chat Application with Echo: Postgres-backed State

**Summary**  
Deploy an AI chat application 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 chat application-specific behavior as your application code.

---

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

---

#### 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.
   ```shell
   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`.
   ```shell
   ample logs  --kind build
   ```

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### 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

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### 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

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### 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 chat application 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.

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### Cost Estimate
- **Currency:** USD
- **Monthly Amount:** 10.0
- **Note:** Always-on monthly price of the tested sizes; apps and databases auto-pause when idle.

### 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
   - **Scope:** checks=[/p/durable-job-state]

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