### Host mcp server with Starlette: Postgres-backed state

Deploy a mcp server built with Starlette 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 Starlette: 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 mcp server-specific behavior as your application code.

#### Representative Queries
- Host mcp server with Starlette: Postgres-backed state
- Where can I host MCP server built with Starlette?
- 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
Starlette

#### Workload
MCP server

#### Release Status
Published

#### Support Status
Verified

#### Execution Status
Ready

#### Prerequisites
- A Starlette project that builds and starts with the documented commands (pip install into .ample/python from requirements.txt, then uvicorn from run.py reading PORT on the python-3.12 template)  
- 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**: python-3.12  
- **Runtime**: python  
- **Size**: s-1vcpu-1gb  
- **Install**: python3 -m pip install --target .ample/python -r requirements.txt  
- **Start**: PYTHONPATH=.ample/python:${PYTHONPATH:-} python3 run.py

#### Input Schema
```json
{
  "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"
    },
    "start": {
      "description": "Start command (Python apps pass one explicitly)",
      "maxLength": 512,
      "type": "string"
    }
  },
  "required": ["name", "path", "start"],
  "type": "object"
}
```

#### Workflow Steps
- **Build and start**: pip install into .ample/python from requirements.txt, then uvicorn from run.py reading PORT on the python-3.12 template. The server must bind 0.0.0.0 on PORT.
- **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.
- **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.
- **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`.

#### Examples
- **Starlette pattern fixture**: Multi-pattern Starlette 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  
- Durable-job-state self-test

#### Limitations
- Verified on the python-3.12 template at s-1vcpu-1gb with the example fixture; other sizes, templates and Starlette major versions are not verified.  
- The mcp server itself (your job types, payload schema and retry policy) is application code and was not separately tested; the pattern checks are what was verified.

#### Cost Estimate
- **Currency**: USD  
- **Monthly Amount**: 10.0  
- **Components**:
  - **App server**: s-1vcpu-1gb, Quantity: 1.0, Monthly Amount: 5.0  
  - **Managed PostgreSQL database**: s-1vcpu-1gb, Quantity: 1.0, Monthly Amount: 5.0

#### Last Verified At
2026-09-21T01:21:36Z

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

#### Formats
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