# Host ai chat application with Gin: Postgres-backed state

Deploy a ai chat application built with Gin 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 Gin: 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 Gin: Postgres-backed state
- Where can I host AI chat application built with Gin?
- I need a durable state schema and retry/recovery semantics implemented by application code.

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

## Infrastructure Requirements
### Compute
- **Label:** 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
- **Label:** 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.

## Framework
Gin

## Workload
AI chat application

## Release Status
published

## Support Status
verified

## Execution Status
ready

## Prerequisites
1. A Gin 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))
2. A PostgreSQL driver reading DATABASE_URL at runtime (auto-provisioned when omitted, or supplied with --env)
3. An Ample account token with servers:write, databases:read

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

## Input Schema
- **Type:** object  
- **Required:** name, path  
- **Properties:**  
  - **name**:  
    - **Type:** string  
    - **MaxLength:** 63  
    - **MinLength:** 1  
    - **Pattern:** ^[a-z0-9-]+$  
  - **path**:  
    - **Type:** string  
    - **MaxLength:** 512  
    - **MinLength:** 1  
  - **env**:  
    - **Type:** array  
    - **Items:**  
      - **Type:** string  
      - **Pattern:** ^[A-Z][A-Z0-9_]*=.*$  
    - **MaxItems:** 50  
  - **release_command**:  
    - **Type:** string  
    - **MaxLength:** 512

## 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
1. **App responds on its public URL**  
   - **Kind:** http_get  
   - **Path:** /  
   - **Expect:** ample canary gin patterns
2. **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 Gin 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.

## Cost Estimate
- **Currency:** USD
- **Monthly Amount:** 10.0
- **Components:**  
  - App server:  
      - Size: s-1vcpu-1gb  
      - Quantity: 1.0  
      - Monthly Amount: 5.0
  - 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.

## Evidence Summary
1. **Kind:** canary_run  
   - **Summary:** Gin pattern fixture deployed on Ample; checks passed for durable-job-state and configuration-secrets.
   - **Observed At:** 2026-09-21T01:15:54Z  
2. **Kind:** canary_run  
   - **Summary:** The same Gin app deployed with a --release-command migration; the marker it created was readable after activation.
   - **Observed At:** 2026-09-20T02:43:30Z

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

## Formats
- **HTML:** [Link](/content/recipes/ai-chat-application/gin/persistent-state/index.html)  
- **Markdown:** [Link](/content/recipes/ai-chat-application/gin/persistent-state.md)  
- **JSON:** [Link](https://api.ample.computer/v1/catalog/recipes/page%3Arecipes%3Aai-chat-application%3Agin%3Apersistent-state)

## Next Actions
1. **Browse the catalog index**  
   - **Method:** GET
   - **Relative Path:** /v1/catalog
2. **Search published recipes by intent, stack and constraints**  
   - **Method:** POST  
   - **Relative Path:** /v1/catalog/search
   - **Parameters:**  
     - **Body:** { "limit": 5, "query": "Host ai chat application with Gin: Postgres-backed state" }  
3. **Prepare a side-effect-free deployment plan for an authorized project**  
   - **Method:** POST  
   - **Relative Path:** /v1/catalog/plan  
4. **Read the existing agent authentication setup**  
   - **Method:** GET  
   - **Relative Path:** /mcp/setup  
5. **Browse AI chat application**  
   - **Method:** GET  
   - **Relative Path:** /v1/catalog/nodes/workload%3Aai-chat-application  
6. **Browse Gin**  
   - **Method:** GET  
   - **Relative Path:** /v1/catalog/nodes/stack%3Aframework-gin  
7. **Browse Durable job state**  
   - **Method:** GET  
   - **Relative Path:** /v1/catalog/nodes/pattern%3Adurable-job-state  
8. **Browse Deploy AI app**  
   - **Method:** GET  
   - **Relative Path:** /v1/catalog/nodes/intent%3Adeploy-ai-app