Shopify Node.js Backend Build

I’m building a custom Shopify app and need the entire server-side logic put in place. I need help with enhancing the storefront but mostly what’s missing is a solid Node.js backend that will run on Railway and persist data in PostgreSQL.

Here’s what I need from you:

• Spin up a clean Node.js project (Express or another lightweight framework is fine) and connect it to a Railway-hosted PostgreSQL instance.
• Implement the Shopify OAuth flow so shops can install the app and grant the required scopes.
• Expose REST endpoints that my frontend can call for product, order and customer data, plus a secure webhook handler so Shopify events are captured reliably.
• Use environment variables for all secrets, add simple logging and write a short README so I can reproduce the setup locally before we go live on Railway.

Acceptance criteria
– Install flow completes without errors and returns a valid access token.
– All endpoints respond with mock JSON when called with a test token.
– Webhook handler verifies HMAC and stores the payload in PostgreSQL.
– Project deploys on Railway with one click and passes a quick smoke test I’ll share.

If you’ve shipped Node.js apps on Railway before, this should be straightforward. Let me know your timeframe and any clarifying questions—looking forward to getting this backend online.