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PHP backend case study

ShopFlow E-commerce

Context: an e-commerce mock with checkout, payment, and backoffice order handling. The problem is that cart state, pricing, and payment status cannot depend on frontend state.

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Case study

Technical scope

Some repositories are private until the work is closed. Project scope, technical decisions, and operating scenarios are described on the page. I can discuss the code during a technical conversation.

01

Problem

  • The shop demo should show the complete commerce lifecycle, not only a checkout form: product discovery, cart state, customer account, payment, and backoffice order handling.
  • The key risks are inconsistent checkout pricing, duplicate payment attempts, webhook replay, inventory drift, and admin operations without auditability or permission checks.
02

Technical decision

  • Backend cart as the source of truth, server-side pricing, Idempotency-Key for checkout, signed webhooks, and an audit log for backoffice operations.
  • The backend is the source of truth for cart state, prices, discounts, shipping, and availability; the frontend displays the result but does not own the final order state.
  • Checkout, cart, customer account, payments, and webhooks are coordinated by separate application services, keeping controllers as a thin HTTP layer.
03

Result

  • The project shows design for a critical business flow: checkout, payment retry, order status, fulfillment, and operational reports.
  • Storefront: product catalog, search, filters, sorting, product pages, wishlist, recently viewed, mini cart, and customer help center.
  • Customer flow: registration, login, shipping profile, order history, checkout prefill, and guest cart merge after login.
  • Backoffice: products, inventory, orders, payments, fulfillment tracking, CSV/JSON reports, audit log, roles, and maintenance panel.
04

Stack

  • PHP / Checkout / Payments / Webhooks
  • composer install
  • composer serve
  • composer smoke-local