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  1. Work
  2. Web and product engineering

Multi-vendor online shop with several payment methods (earlier work)

An earlier multi-vendor online shop with seller shops, checkout with several payment methods confirmed by asynchronous callbacks, a wallet, two-factor sign-in, identity verification and seller reputation scores.

Problem

Independent sellers wanted to open their own shops inside one online shop and accept payment by several methods, while buyers needed reasons to trust sellers they had never dealt with.

Goal

A shared online shop where sellers run their own shops and catalogues, buyers check out with the payment method they prefer, every payment is confirmed by the payment provider before an order moves forward, and trust is built through verified identities, strong sign-in and seller reputation scores.

My role

Contributed to the commerce core (cart, checkout, orders and transactions) and to the seller reputation feature, working alongside other developers on the wider codebase.

Solution

A server-rendered MVC web application with separate storefront and admin areas. The storefront covers seller shops, catalogue, cart, checkout and orders. Payment adapters handle several payment methods, each confirmed through asynchronous callbacks, and a wallet handles balances and transfers.

How it works

Sellers open a shop and manage products with attributes and variants, including bulk upload from a spreadsheet file.

Buyers add items from several shops to one cart and check out with the payment method they prefer.

The payment provider confirms each payment through an asynchronous callback, and only a confirmed payment moves the order forward; the order and its transactions are recorded against the buyer, the seller and the wallet.

Scheduled command-line jobs push listings to a search index and recalculate seller reputation scores.

Onboarding adds SMS and authenticator-app two-factor sign-in and document-based identity verification through a verification provider.

The admin area runs as a single-page shell with hash-based routing over AJAX, alongside messaging, support tickets and simple content pages.

Technical challenges

Order state driven by asynchronous payment callbacks from several providers, rather than by the buyer's browser returning from checkout.

Keeping wallet balances consistent across payments, orders and transfers.

Carts that span several sellers.

Layering identity verification and two-factor sign-in into onboarding.

Capabilities

  • Seller shops and catalogue management with bulk upload
  • Multi-seller cart, checkout and orders
  • Several payment methods confirmed by callbacks
  • Wallet with balances and transfers
  • SMS and authenticator-app two-factor sign-in
  • Document-based identity verification
  • Seller reputation scores
  • Search indexing
  • Messaging and support tickets
  • Single-page admin area

Technology

  • PHP with an MVC framework
  • MySQL
  • jQuery single-page admin with hash routing
  • Payment provider webhooks
  • OAuth social sign-in
  • TOTP and SMS two-factor authentication
  • Identity verification provider
  • Cloud object storage for images
  • Hosted search index

Impact

A working multi-vendor online shop that combined several payment methods with trust features, and early hands-on experience of payment callbacks, wallets and identity checks.

Skills demonstrated

  • E-commerce order and payment flows
  • Payment and webhook integration
  • Wallet and balance handling
  • Authentication and identity verification
  • Team development in a shared codebase

All work