Getting search results back is easy; getting the right products in the right order is the real work. A deep-dive on relevance tuning for a store — boosting by business signals, synonyms, typo handling, zero-results, and measuring whether your changes actually help.
Checkout is where a store makes or loses the sale, and most carts are abandoned there. A deep-dive on the engineering and UX of a high-converting checkout — fewer steps, guest checkout, honest validation, and the friction that quietly costs you orders.
Taking money is the part of e-commerce you cannot afford to get wrong. A deep-dive on integrating a payment gateway correctly — tokenization, idempotency keys, webhooks as the source of truth, and modelling a payment as a state machine.
When a store needs search, the reflex is Elasticsearch — but Postgres full-text search has grown up. A head-to-head for the e-commerce case: ranking, facets, typo tolerance, and the operational cost that decides it.
A catalog page that's fast for ten users can fall over for ten thousand. A deep-dive on the layers of caching that keep it fast — fragment caching, HTTP/CDN caching, low-level caching — and the hard part: invalidation and stampedes.
Selling across countries means translating not just your interface but your data, your URLs, your formats, and your SEO. A deep-dive on Rails i18n at scale — locale files, translated content, locale routing, and the traps.
A product catalog is mostly images, and naive image handling will sink it. A deep-dive on building an image pipeline that scales — keeping originals, generating variants in the background, offloading to a CDN, and not melting your web servers.
Selling in more than one currency sounds like a display problem and turns out to be a data-modelling one. A deep-dive on representing money correctly, storing prices across currencies, exchange rates, rounding, and the mistakes that cost real money.