# Host REST API with ASP.NET Core: Postgres-backed state

Deploy a REST API built with ASP.NET Core 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 ASP.NET Core: 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 REST API-specific behavior as your application code.

## Representative Queries
- Host REST API with ASP.NET Core: Postgres-backed state
- Where can I host REST API built with ASP.NET Core?
- I need a durable state schema and retry/recovery semantics implemented by application code.

## Resource Requirements
- Compute
- Postgres

## Infrastructure Requirements
1. **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.
2. **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
ASP.NET Core

## Workload
REST API

## Execution Status
Ready

## Prerequisites
- A ASP.NET Core project that builds and starts with the documented commands (dotnet publish -c Release -o out in the builder, then dotnet .dll on the dotnet-10 template with ASPNETCORE_URLS bound to PORT)
- 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**: dotnet-10  
- **Runtime**: dotnet  
- **Size**: s-1vcpu-1gb  
- **Build**: dotnet publish -c Release -o out  
- **Start**: ASPNETCORE_URLS=http://0.0.0.0:$PORT dotnet out/$(basename $(ls out/*.runtimeconfig.json | head -n 1) .runtimeconfig.json).dll

## Workflow Steps
1. **Build and start**  
   - Command: dotnet publish -c Release -o out in the builder, then dotnet .dll on the dotnet-10 template with ASPNETCORE_URLS bound to PORT. 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**  
   - Command: ample deploy . --name [app_name] --public  
   - 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.
4. **Verify**  
   - Command: ample logs --kind build  
   - 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`.

## Examples
- **ASP.NET Core pattern fixture**  
  Description: Multi-pattern ASP.NET Core 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 asp net core 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 dotnet-10 template at s-1vcpu-1gb with the example fixture; other sizes, templates, and ASP.NET Core major versions are not verified.
- The REST API 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  
- **Authoritative**: true  
- **Basis**: size prices from pricing.toml (loaded by the API) at build revision 1ac5595375130d45290090e82ed0f554ccd45405-dirty
- **Components**:
  1. **App server**  
      - Size: s-1vcpu-1gb  
      - Quantity: 1.0  
      - Monthly Amount: 5.0
  2. **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: ASP.NET Core pattern fixture deployed on Ample. All checks passed for durable-job-state and configuration-secrets.
- **Last Verified At**: 2026-09-21T01:15:54Z

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

## Formats
- HTML: [Link](/content/recipes/rest-api/asp-net-core/persistent-state/index.html)  
- Markdown: [Link](/content/recipes/rest-api/asp-net-core/persistent-state.md)  
- JSON: [Link](https://api.ample.computer/v1/catalog/recipes/page%3Arecipes%3Arest-api%3Aasp-net-core%3Apersistent-state)

## Next Actions
- Browse the catalog index
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- Read the existing agent authentication setup
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