# Custom Ecommerce Development | Headless Storefronts on Next.js | Alher Tech > Headless ecommerce on Next.js with Shopify, Saleor or Medusa. Sub-second LCP, multi-currency checkout, ERP/PIM sync, B2B portals. 8-14 weeks. - Canonical page: https://alhertech.com/en/solutions/ecommerce-development/ - Site: Alher Tech (custom software, AI agents and SEO engineering, https://alhertech.com/) - Contact: https://alhertech.com/en/contact/ --- Headless ecommerce on Next.js with Shopify, Saleor or Medusa as the engine: sub-second LCP, custom checkout, ERP and PIM wired in. Live in 8-14 weeks. ## What Ecommerce Delivers - **Storefront That Loads Like a Static Site**: Off-the-shelf themes peak around €1-3M GMV. Past that, the bottleneck is conversion (slow PDPs, generic checkout), data flow (manual stock updates, broken returns) or assortment complexity (B2B tiers, made-to-order, configurators). Headless storefronts with the commerce engine kept clean fix exactly those three, without rebuilding the catalogue or the order management you already trust. - **Checkout Designed Around Your Best Buyer**: Single-step checkout for repeat buyers, guest path for first-timers, Apple Pay and Google Pay surfaced from the cart, address autocomplete, real-time tax. We measure the funnel field by field and rip out anything that costs more than 0.3 points of conversion. - **PIM and ERP Stay the Source of Truth**: Akeneo, Pimcore, SAP, Odoo or your homegrown tool keeps owning the data; the storefront syncs through queues, not through the PIM hitting a public web request. Stock, prices and product copy update without anyone editing two places. - **B2B and B2C on the Same Codebase**: Customer-specific catalogues, negotiated prices, payment-by-invoice, approval workflows, quote-to-order. Login flips the storefront into B2B mode; same checkout component, different rules, and no separate site to maintain. - **Abandoned-Cart and Re-Engagement Built In**: Persistent cart across devices, abandoned-cart emails through Klaviyo or Customer.io with deep-linked recovery URLs, browse-abandonment for high-intent product views. The flows live in code and are A/B-testable, not hand-held in a marketing tool. - **International Without a Second Site**: Multi-currency pricing tied to country detection, multilingual content from your PIM, geo-aware shipping rules, IOSS/OSS-compliant VAT in the EU, fraud rules tuned per market. Adding Germany or Mexico is a config change, not a project. ## How We Build Your Ecommerce - **Commerce Engine Decision**: Day one we choose between Shopify (fastest path, payments included), Saleor (open-source, GraphQL-native, best for complex catalogues) or Medusa (Node-native, fully self-hosted). The pick locks pricing, payouts and roadmap. - **Catalogue and Data Migration**: We pull products, variants, customers and historical orders from your old platform with a re-runnable script. Redirect map for SEO is built at the same time so no URL gets lost when you cut over. - **Storefront Sprint**: Home, PLP, PDP, cart, checkout, all built in Next.js with your design system, component-tested, published behind a preview URL daily. Performance budget enforced on every PR. - **Operational Wiring**: ERP/PIM sync, OMS, payment gateways, shipping carriers, returns portal, customer support deep-links. The first real order that ships in a brown box on the warehouse floor is the milestone we celebrate, not the deploy. - **SEO + CRO Hardening**: Schema.org for products and breadcrumbs, hreflang for multi-region, Core Web Vitals locked under thresholds, GA4 + server-side conversion tracking, A/B test framework on key pages. We launch knowing the next twenty experiments. - **Cutover Weekend**: Final delta migration, DNS swap, redirect map active, monitoring on. We sit in your war room until first-day metrics confirm conversion is at least flat. Usually it is up. ## High-performance stack used by global leaders React/Next.js/Angular on the frontend and Java 21 + Spring Boot + PostgreSQL 14 on the backend: the same stack that BBVA, ING, and Netflix use for their security and performance. **We are Shopify Partners.** And we do not stop at the theme: we build the storefront in code, so you depend on no third party and the store is 100% yours. [Shopify](https://www.shopify.com) ## Ecommerce: FAQ ### How much does a custom ecommerce build cost? A headless Shopify storefront with custom design, 1-2 integrations and a clean migration runs €30,000 to €70,000. A self-hosted Saleor or Medusa build with full B2B, multi-region and ERP sync lands at €70,000 to €160,000. We always quote a fixed first phase after a discovery call so the number is anchored to scope. ### How long until we cut over from the old store? Eight to fourteen weeks for a typical migration. The variability is almost always in catalogue cleanup and integration count, not in the storefront itself. We start the redirect map and SEO audit in week one so the cutover does not torpedo organic traffic. ### Shopify, Saleor or Medusa: which one do we pick? Shopify if you want payments and tax solved out of the box and your catalogue is under ~50k SKUs without exotic rules. Saleor if you need a GraphQL-native engine, complex pricing tiers and full ownership. Medusa when self-hosted Node alignment matters and you want to extend the engine itself. We pick during the discovery, not after the contract. ### Can you migrate without losing SEO? Yes, and it is the part most agencies underplay. We crawl your old site, generate a 1:1 URL redirect map, preserve canonical URLs, port hreflang clusters, keep schema markup and run pre-launch synthetic crawls against staging. Most clients see no organic dip past week two. ### Do you support B2B portals and quote-to-order? Yes. Customer-specific pricelists, MOQ enforcement, payment terms (net 30/60/90), purchase-order numbers in checkout, quote requests, sales-rep dashboards. Built on the same storefront, switched on by the logged-in user role, with no parallel site. ### How are abandoned carts handled? Cart state lives in our backend, not just the browser, so it survives device switches and re-logins. Klaviyo or Customer.io fires a configurable flow (1h, 24h, 72h emails plus an SMS for high-AOV carts) with deep-linked recovery URLs that re-hydrate the exact cart, even after stock changes. ### What stays with us after launch? You own the Next.js repo, the deployment infrastructure, the database, the domain and every third-party account. We deliver a runbook for operational tasks (refunds, edge-case orders, festive traffic prep), a Looker Studio dashboard pinned to your KPIs, and a 30/60/90 retainer if you want one. ### Do you work with clients globally? Yes. We work fully remote with clients across Spain, Europe, the US and LATAM. Time zones, video calls and live demos at every milestone.