E-commerce development, connected to the rest of your business

What does e-commerce development cover beyond the shop?

The storefront is the visible part of an online shop, and often the smaller part of the work. The rest is data flow: orders reaching the warehouse and accounting, stock and prices staying in sync, customers arriving in the CRM with their purchase history, and the right message reaching a buyer at the right moment. We build the shop and those connections as one project, because most e-commerce problems sit between systems, not on the product page.

Shopify, WooCommerce or custom?

Platform	Fits when	Trade-offs
Shopify	You want a hosted platform, a fast launch and a large app ecosystem	Deeper checkout customization requires Shopify Plus; payment providers other than Shopify Payments add Shopify transaction fees
WooCommerce	You already run WordPress or want full control of hosting and data	Plugin updates, security and performance are your responsibility
Custom or headless	Pricing, product configuration or B2B logic doesn’t fit a standard shop	Higher build and running cost; every feature is yours to maintain

For most retailers a standard platform with a few well-chosen integrations is the right start. We recommend custom development where the platform genuinely stops, and we prefer a small custom app to bending a theme until it breaks.

How we build and connect a shop

Product data first. Variants, languages, price lists, tax categories and media are modeled before the theme, so filters, product feeds and translations all work from one clean source.

Checkout on the payment provider. Card data is handled by the platform’s payment provider, never by your servers, which keeps your PCI DSS scope small. The payment methods you can offer depend on that provider, so we confirm the combination before committing to it.

Integrations that tolerate duplicates. Platforms such as Shopify deliver webhooks at least once, so the same order event can arrive twice. We verify each webhook’s HMAC signature, record its ID and process it idempotently in a job queue with retries, so a repeated event never creates a second order in your ERP.

One owner per field. For stock, prices and customer data we decide which system is authoritative and in which direction data flows. Most sync bugs come from two systems editing the same field.

Messages based on real events. Order, shipping and account emails are transactional. Abandoned-cart, review and win-back messages are marketing: they require consent and re-check the order status right before sending, so nobody gets a reminder for a cart they already paid for.

What goes wrong in e-commerce projects

• Overselling. Stock syncs every hour while orders arrive every minute. Event-driven stock updates and a safety buffer on low-stock items prevent it.
• Revenue counted twice. A reloaded thank-you page fires the purchase event again. We track orders server-side from the order event itself.
• Rankings lost after a platform change. Product and category URLs change and old links break. We map and redirect every URL, including category and filter pages that earned traffic.
• App sprawl. A dozen apps each add scripts and slow the shop down. We audit overlapping apps and replace them with one integration where that pays off.

Compliance for online shops

For customer data processed in Switzerland, the revised FADP (Art. 19) requires the privacy notice to name the countries to which the data is disclosed, which matters when the shop platform and marketing tools run abroad; the GDPR has a similar duty for transfers out of the EU. Under the Swiss Unfair Competition Act (UCA Art. 3 para. 1 let. o), marketing emails and SMS sent in bulk need prior consent, correct sender identification and an easy opt-out, and EU countries set similar rules; we treat abandoned-cart reminders as marketing and ask for consent at checkout. If you sell to consumers in the EU, the European Accessibility Act has applied to e-commerce services since 28 June 2025, with an exemption for microenterprises. We build storefronts to WCAG 2.1 AA.

What drives cost and timeline

Driver	Effect on effort
Catalog size and variants	Import, data cleanup and filter logic grow with the catalog.
Languages and markets	Each language and currency needs content, SEO and checkout testing.
Payments and shipping	Providers, rates and rules differ by market.
Integrations	ERP, inventory, CRM and accounting connections are usually the largest block.
Custom apps	Behavior the platform lacks needs its own development and upkeep.
Migration	Products, customers, orders and URLs from an old shop must be moved and checked.
Message flows	Each automated sequence needs copy, rules, consent handling and tests.

After discovery we send a fixed-price proposal for a defined scope, or a phased plan that launches the shop first and adds integrations and automation in order of payback. The general cost drivers of web projects are covered in our website cost guide.

How it connects to the rest of your system

A shop produces the most useful customer data you have. We connect it to CRM and sales automation, to email and SMS automation for post-purchase flows, to chatbots that answer order questions on WhatsApp, and to accounting and logistics through API integrations. The end-to-end setup is described under e-commerce automation.

Why Sensaria

Our e-commerce work sits where platforms meet other systems. We have built a Shopify app on Remix and Polaris with 11 Shopify Flow extensions, a theme app extension, app billing and Shopify’s mandatory GDPR webhooks. It sends WhatsApp messages through a provider’s Business API, with message templates, chatbot triggers and cart recovery. We have also built a WooCommerce integration inside a WordPress plugin that turns new orders into CRM deals. Sensaria AG is based in Lugano, Switzerland, and works in English, Italian, German and French.