E-Commerce Development

E-Commerce Development — questions and answers

How should a pricing page handle tax, currency and shipping display?

It depends on jurisdiction and audience. Consumer selling in much of Europe requires tax-inclusive display, while North American practice shows tax added at checkout, and business-to-business contexts often show figures excluding tax. Currency conversion needs a stated rate source and rounding rule, since a figure that shifts between listing and checkout erodes trust. Shipping is best surfaced early, because an unexpected charge at the final step is a common abandonment point.

How are product variants modelled without duplicating products?

As one product with option dimensions — size, colour, material — where each valid combination is a variant carrying its own stock keeping unit, stock level and sometimes weight or image. This keeps one page, one set of reviews and one canonical URL, while letting inventory and fulfilment work per variant. Modelling each colour as a separate product splits reviews and search signals and multiplies maintenance.

Why must payment webhooks be idempotent?

Providers retry delivery when they don't get a clean acknowledgement, so the same event can arrive more than once, sometimes out of order. Recording the provider's event identifier and ignoring events already processed keeps a retry from creating a second order, sending a second confirmation or subtracting stock twice. Verifying the signature against the raw request body matters too, since parsing first can invalidate the check.

What actually keeps card data out of scope for a store?

Never letting raw card details touch the merchant's own servers or code. Hosted fields or provider-supplied elements collect the number inside an iframe belonging to the payment provider and return a token, so the merchant stores a reference rather than a card. Building a custom card form that posts to the backend pulls the whole system into a far heavier compliance obligation for no functional gain.

How do stock levels stay accurate across several sales channels?

One system holds the authoritative quantity and every channel reads from it, rather than each keeping its own count. Updates flow through a single path, ideally with reservations held during checkout so two buyers can't claim the last unit. Where a channel only syncs periodically, a buffer quantity reduces oversells, at the cost of appearing out of stock while units remain.

What breaks during a platform migration, and what prevents it?

Order history, customer accounts with unusable password hashes, tax records, and URLs that external sites and search engines already point at. A migration plan maps old addresses to new ones with permanent redirects, exports and reconciles orders rather than starting fresh, and runs both systems against real data before switching. Verifying counts and totals after import catches silent truncation early.