## Diagnose deployment failures for Fastify

### Summary
Deployment diagnostics for a Fastify app on Ample. Verified on Fastify: the same app deployed with a deliberate boot failure (CANARY_FAIL=boot): `ample deploy` exited 1 with a coded failure (health_check_failed when the process dies at boot, public_ingress_failed when the framework boots but every request answers 500) and the app's own error line was readable with `ample logs  --kind runtime`, so the cause is read from the framework's output rather than guessed. Build and start: npm install, npm run build --if-present, npm run start on the node-22 template.

### Prerequisites
- A Fastify project (npm install, npm run build --if-present, npm run start on the node-22 template)
- An Ample account token with servers:write

### Resource Requirements
- **Primitive:** Compute

### 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.

### Workflow Steps
1. **Read the failure code**  
   Deploy is synchronous. Exit 1 with build_failed means the isolated build failed; health_check_failed means the app built but never answered on PORT (it crashed at boot or bound the wrong port); public_ingress_failed means it answered on PORT but the public URL returned an error status (a request handler or bootstrap failed); exit 2 means a required preflight action is blocking.

2. **Read the build log**  
   The last lines name the failing command and its output.  
   ```shell
   ample logs  --kind build
   ```

3. **Read the runtime log**  
   For health_check_failed the runtime log carries the Fastify process output: in the verified run the deliberate boot failure's own error line was there, followed by the platform's health-check verdict and the start command it ran.  
   ```shell
   ample logs  --kind runtime
   ```

4. **Fix and redeploy once**  
   Change the source, the environment or the command override, then run ample deploy again. Do not loop deploys to poll status; an unchanged redeploy is a no-op.

5. **Verify**  
   Fetch the live URL on the example; on failure read the build and runtime logs.  
   ```shell
   ample logs  --kind build
   ```

### Examples
- **Fastify pattern fixture**  
  Verified deployment diagnostics on Fastify.  
  Source Reference: `tests/deploy-canaries/fastify-patterns`

### Success Checks
- **failed deploy reports health_check_failed synchronously**  
  Expect: `ample deploy exits 1 with error.code health_check_failed`
- **runtime log carries the app's own error line**  
  Expect: `ample logs  --kind runtime shows the framework's error output before the health-check verdict`

### Limitations
- Verified on the node-22 template at s-1vcpu-1gb; other sizes and Fastify major versions are not verified.
- Region, compliance attestations and request-duration limits are unknown and not claimed.

### Cost Estimate
- **Currency**: USD  
- **Monthly Amount**: 5.00  
- **Basis**: size prices from pricing.toml (loaded by the API) at build revision 1ac5595375130d45290090e82ed0f554ccd45405-dirty
- **Components**:
  - **App Server**: s-1vcpu-1gb, Quantity: 1.0, Monthly Amount: 5.00  
- **Note**: Always-on monthly price of the tested sizes; apps auto-pause when idle.

### Evidence Summary
- **Kind**: Canary run  
  Summary: Fastify pattern fixture deployed on Ample with CANARY_FAIL=boot (npm install, npm run build --if-present, npm run start on the node-22 template); the same app deployed with a deliberate boot failure (CANARY_FAIL=boot): `ample deploy` exited 1 with a coded failure (health_check_failed when the process dies at boot, public_ingress_failed when the framework boots but every request answers 500) and the app's own error line was readable with `ample logs  --kind runtime`, so the cause is read from the framework's output rather than guessed.
- **Observed At**: 2026-09-21T02:23:07Z  
- **Expires At**: 2027-03-20T02:23:07Z

### Next Actions
- **Browse the catalog index**: `GET /v1/catalog`
- **Search published recipes by intent, stack and constraints**: `POST /v1/catalog/search`  
  Request Body: `{"limit":5,"query":"Diagnose deployment failures for Fastify"}`  
- **Prepare a side-effect-free deployment plan for an authorized project**: `POST /v1/catalog/plan`  
  Request Body: `{ "inputs":{}, "projectId":"", "recipeId":"page:guides:fastify:deployment-diagnostics", "recipeRevision":"r1" }`
- **Read the existing agent authentication setup**: `GET /mcp/setup`