Can I vibe code Appstle?

Build a production-ready Node.js/TypeScript and React subscription app for Shopify using the official Shopify App Remix framework and Storefront API.

The system must handle three core entities:
1. Subscription Plans (SellingPlanGroups, SellingPlans, billing policies, delivery policies, and pricing policies synced directly to Shopify's GraphQL Admin API).
2. Subscription Contracts (Customer subscriptions, payment method tokens, active status, billing attempt histories, next delivery dates).
3. Customer Portal (App Proxy endpoints allowing buyers to pause, resume, skip, swap products, and update delivery frequencies).

TECHNICAL ARCHITECTURE & INTEGRATIONS:
- Use Prisma ORM with PostgreSQL to store local sync copies of SellingPlanGroups and SubscriptionContracts.
- Integrate directly with Shopify's GraphQL Admin API to issue `sellingPlanGroupCreate`, `subscriptionContractUpdate`, and `subscriptionDraftCommit` mutations.
- Build a Shopify App Proxy route at `/apps/subscriptions/portal` returning a Liquid-compatible HTML string or React-hydrated UI for the buyer portal.
- Implement webhooks using Shopify Webhook Handlers for `SUBSCRIPTION_CONTRACTS_CREATE`, `SUBSCRIPTION_CONTRACTS_UPDATE`, and `SUBSCRIPTION_BILLING_ATTEMPTS_FAILURE`.

RECURRING BILLING & DUNNING ENGINE:
- Create a background worker (using BullMQ or Redis) that polls for due subscription contracts daily.
- For contracts where `nextBillingDate <= NOW()`, issue the `subscriptionBillingAttemptCreate` GraphQL mutation against Shopify's API.
- If a billing attempt fails, execute a dunning schedule (Retry at Day +1, Day +3, Day +7). Send transactional email notifications via Postmark or SendGrid API on failure.
- Update contract status to 'PAUSED' or 'CANCELLED' if all retries fail.

PRODUCT SWAP & BUILD-A-BOX LOGIC:
- Implement an endpoint allowing buyers to swap an active subscription variant for a different product variant ID via `subscriptionContractProductChange`.
- Validate inventory levels using the Shopify Admin API (`inventoryItems`) before confirming swaps or upcoming recurring charges.

FAILURE MODES & EDGE CASES TO HANDLE:
- Race conditions when a customer pauses a subscription seconds before an automated billing cron runs. Use atomic database locks or Redis locks on the `subscriptionContractId`.
- Out-of-sync payment tokens when a customer updates their card on file in Shopify Customer Accounts. Ensure the `paymentMethodId` is dynamically fetched before generating a billing attempt.

OUT OF SCOPE:
- Native iOS/Android mobile SDKs.
- Custom invoicing outside of Shopify's checkout payment gateway.
- In-house credit card vaulting (delegate entirely to Shopify Payments/Stripe).

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