# Host AI Workflow Runner with Axum: Postgres-backed State

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

## 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.

## Framework
- Axum

## Workload
- AI workflow runner

## Release Status
- Published

## Support Status
- Verified

## Execution Status
- Ready

## Prerequisites
- A Axum project that builds and starts with the documented commands (`cargo build --release` in the Rust builder image (stable toolchain, Cargo.lock committed, pure-Rust dependencies), then the release binary on the `ubuntu-24.04` template reading `PORT` and `DATABASE_URL`)
- 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**: rust  
- **Size**: s-1vcpu-2gb  
- **Build**: `cargo build --release`  
- **Start**: `./$(ls target/release/*.d | grep -v '/lib' | head -n 1 | sed 's/\.d$//')`

## Workflow Steps
1. **Build and Start**  
   `cargo build --release` in the Rust builder image (stable toolchain, Cargo.lock committed, pure-Rust dependencies), then the release binary on the `ubuntu-24.04` template reading `PORT` and `DATABASE_URL`. 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`

## Examples
- **Axum Pattern Fixture**  
  Multi-pattern Axum app whose durable job state module was checked live; the module is under `tests/deploy-canaries/_pattern-modules`.

## Success Checks
- **App responds on its public URL**  
   Kind: `http_get`  
   Path: `/`  
   Expect: `ample canary axum 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-2gb` with the example fixture; other sizes, templates and Axum 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
- **Monthly Amount**: 10.0 USD
- **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: Axum pattern fixture deployed on Ample (cargo build --release in the rust builder image (stable toolchain, Cargo.lock committed, pure-Rust dependencies), then the release binary on the `ubuntu-24.04` template reading `PORT` and `DATABASE_URL`); checks passed for durable-job-state and configuration-secrets. Pattern proof: 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).
  Observed At: `2026-09-21T02:46:37Z`  
  Implementation Revision: `1d28ae0-dirty (CLI 0.1.21)`  
  Expires At: `2027-03-20T02:46:37Z`

## 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-workflow-runner/axum/persistent-state/index.html)
- Markdown: [Link](/content/recipes/ai-workflow-runner/axum/persistent-state.md)
- JSON: [Link](https://api.ample.computer/v1/catalog/recipes/page%3Arecipes%3Aai-workflow-runner%3Aaxum%3Apersistent-state)