What a custom online shop is
A custom online shop is an e-commerce site built around your catalogue, your pricing rules and your ERP, instead of the company adapting to an off-the-shelf platform. The ERP remains the main source of data on products, prices and stock, while the shop shows that data to customers and sends orders back to where your team already processes them. There is no double entry and no manual stock reconciliation after every sale.
When an off-the-shelf platform is enough and when you need a custom shop
Many companies do not need a custom online shop. An off-the-shelf e-commerce platform that you pay for by subscription is faster and cheaper if most of the following applies to you:
- the catalogue is small and rarely changes;
- all customers see the same price list;
- you do not keep stock in an ERP, or the ERP does not need to be connected to the shop;
- the usual payment and delivery options are enough for you.
A custom online shop makes sense when:
- the catalogue, prices and stock are already in the ERP, and copying them across by hand causes errors and wastes time;
- business customers have their own price lists, discounts or payment terms;
- stock is spread across several warehouses or branches;
- you sell to both consumers and businesses, with different rules for each group;
- your rules for delivery, packing or reserving goods do not fit into the add-ons of an off-the-shelf platform.
There is also a middle way. If you already have a shop on an off-the-shelf platform and the only problem is retyping data by hand, a reliable connection to the ERP is sometimes enough. We tell you which of these applies to you on the first call.
Connecting to the ERP: products, prices and stock
The ERP connection is the foundation of this kind of online shop. Before the estimate, we check how your ERP provides data: through an API, read-only database access or regular file exports. That determines how often the data can be refreshed and whether an order can be written to the ERP straight away. We describe our general approach to connecting business systems on our AI integration with CRM and ERP systems page.
Products
Product codes, names, categories and attributes such as colour or size come from the ERP. An ERP rarely has good descriptions and photos, so the shop has its own place for sales descriptions, images and documents, and the product code links them to the ERP.
Prices
Price lists, promotions and discounts per customer or customer group are taken from the ERP, together with VAT. A signed-in business customer sees their own prices, and other customers see the public price list. The pricing rules stay in the ERP, so the price in the shop and the price in the ERP do not diverge.
Stock
Stock levels per warehouse are refreshed as often as the ERP allows, and before an order is confirmed, the shop checks availability again where the ERP makes that possible. If the ERP is temporarily unavailable, the shop works with the last known stock levels, and orders wait and are transferred as soon as the connection is back.
Orders
Every order enters the ERP as a document your team already knows how to process, and the customer is linked to an existing business partner record or a new one is created. The delivery status is sent back to the shop, and the customer receives it by email.
Card payments and delivery
We connect card payments through an authorised payment service provider you have a contract with. The customer enters their card details on the provider's secure page or form, so they never pass through your online shop. Alongside cards, you can also offer cash on delivery or bank transfer.
We connect the delivery services for creating shipments and labels, and for the tracking number the customer receives by email. Delivery costs follow the rules you set, for example by weight, basket value or collection method, and the customer can also choose to collect from a branch or a parcel locker.
Speed and SEO of product pages
A product page needs to load quickly and be visible to search engines. That is why:
- pages are generated on the server, so the customer and Google get the full content straight away;
- images are resized automatically and served in modern formats;
- every product has a readable URL, its own title and description, and structured data on price and availability;
- variants of the same product do not create duplicates, and filter combinations are not indexed as separate pages;
- the sitemap updates itself when you add or remove a product;
- when you move from an old shop, we permanently redirect the existing URLs to the new ones, so that you do not lose your search rankings.
We measure page speed and stability with Google's Core Web Vitals, before and after launch.
How we build an online shop, step by step
- A free first call: what you sell, to whom, and where your data is today.
- An ERP check: how it provides data and what can be written back to it.
- Scope, cost estimate and a phased plan, so you know what you get in each phase.
- A first working version in 4–8 weeks: the catalogue from the ERP, the basket, payment and orders back into the ERP.
- Testing with real data and test orders before launch.
- Launch, redirects and monitoring of the first orders.
- Maintenance and upgrades in the next phases.
We build on the technologies we also use in our own products: Next.js and React for the shop, Node.js and PostgreSQL for the backend, Docker and GitLab CI for delivery. You follow progress in the client portal. If you also need an internal tool alongside the shop, see custom software development and web application development.
What the cost of building an online shop depends on
- the number of products, variants and attributes;
- how complex the rules for prices, discounts and promotions are;
- how the shop connects to the ERP, and the quality of the ERP documentation;
- the number of payment methods and delivery services;
- sign-in for business customers with their own price lists;
- a design made specially for you or one adapted from ready-made elements;
- moving from an old shop: content, customers and redirects.
You get the cost estimate after the first call, together with a phased plan.
What you need to prepare
- access to the ERP documentation, or a contact at its vendor;
- a contract with a card payment service provider and with delivery services;
- product descriptions and photos, or a decision on who will prepare them;
- terms of sale, a privacy notice and a cookie policy;
- a list of the URLs of your existing shop, if you have one.
Maintenance after launch
An online shop is not finished on launch day. Maintenance includes hosting on servers in the EU, security updates, backups, monitoring of the ERP synchronisation with an alert when prices or stock are not refreshed on time, and minor changes. New features, such as sign-in for business customers or a chatbot that answers questions about products from your catalogue, are added in later phases.