# Host Subscription Content with SvelteKit: Relational Catalog Data

Deploy a subscription content built with SvelteKit on Ample using the transactional workflows 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 SvelteKit: an optimistic version check and an event row written in the same transaction, a stale update rejected, and a history query over the application-owned events (history=2 conflict=rejected). Not separately tested: your domain records, validation rules and concurrency policy; treat the subscription content-specific behavior as your application code.

## Representative Queries
- Host subscription content with SvelteKit: relational catalog data
- Where can I host Subscription content built with SvelteKit?
- I need catalog tables, transactional update logic and application-level access boundaries.

## Resource Requirements
- Primitive: Compute
- Primitive: Postgres

## Infrastructure Requirements
1. **Compute**  
   Managed x86_64 Firecracker microVMs that auto-pause when idle.  
   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**  
   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
SvelteKit

## Workload
Subscription content

## Release Status
Published

## Support Status
Verified

## Execution Status
Ready

## Prerequisites
- A SvelteKit project that builds and starts with the documented commands (vite build with @sveltejs/adapter-node then node build on the node-22 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**: node-22  
- **Runtime**: node  
- **Size**: s-1vcpu-1gb  
- **Install**: npm install  
- **Build**: npm run build --if-present  
- **Start**: npm run start

## Workflow Steps
1. **Build and start**  
   vite build with @sveltejs/adapter-node then node build on the node-22 template. The server must bind 0.0.0.0 on PORT.

2. **Implement the pattern on PostgreSQL**  
   The fixture's module implements transactional workflows: an optimistic version check and an event row written in the same transaction, a stale update rejected, and a history query over the application-owned events (history=2 conflict=rejected). 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/transactional-workflows) from the example; then run your own checks. On failure read `ample logs  --kind build` then `--kind runtime`.  
   Command: ample logs  --kind build

## Examples
- **SvelteKit pattern fixture**  
  Multi-pattern SvelteKit app whose transactional workflows module was checked live; the module is under tests/deploy-canaries/_pattern-modules.  
  Source Reference: tests/deploy-canaries/sveltekit-patterns

## Limitations
- Verified on the node-22 template at s-1vcpu-1gb with the example fixture; other sizes, templates and SvelteKit major versions are not verified.
- The subscription content itself (your domain records, validation rules and concurrency 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  
- **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. Buckets are allocation-priced per quota and not included.

## Evidence Summary
1. **Canary Run**  
   SvelteKit pattern fixture deployed on Ample; checks passed for transactional-workflows and configuration-secrets.  
   Observed At: 2026-09-20T03:31:44Z

2. **Canary Run**  
   The same SvelteKit app deployed with a --release-command migration; the marker it created was readable after activation.  
   Observed At: 2026-09-20T02:16:51Z

## MCP Binding
- **Registry Ref**: mcp:ample_deploy  
- **Tool Name**: ample_deploy  
- **Required Scopes**: servers:write, databases:read  
- **Binding State**: current

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

## Formats
- [HTML](/content/recipes/subscription-content/sveltekit/relational-catalog/index.html)  
- [Markdown](/content/recipes/subscription-content/sveltekit/relational-catalog.md)  
- [JSON](https://api.ample.computer/v1/catalog/recipes/page%3Arecipes%3Asubscription-content%3Asveltekit%3Arelational-catalog)

## Next Actions
1. **Browse the catalog index**: GET /v1/catalog
2. **Search published recipes by intent, stack, and constraints**: POST /v1/catalog/search
3. **Prepare a side-effect-free deployment plan for an authorized project**: POST /v1/catalog/plan
4. **Read the existing agent authentication setup**: GET /mcp/setup
5. **Browse Subscription content**: GET /v1/catalog/nodes/workload%3Asubscription-content
6. **Browse SvelteKit**: GET /v1/catalog/nodes/stack%3Aframework-sveltekit
7. **Browse Transactional workflows**: GET /v1/catalog/nodes/pattern%3Atransactional-workflows
8. **Browse Deploy web app**: GET /v1/catalog/nodes/intent%3Adeploy-web-app