Custom E-commerce, Shopify or PrestaShop

The hard part of an online store is rarely the store

Almost anyone can open a Shopify or PrestaShop store with a decent theme. The trouble is everything around it: the stock customers see matching the warehouse, orders landing in the back-office system on their own, shipping costing what it should when a basket mixes suppliers, or search finding a spare part by its reference.

That is where we work. At Electrotodo, which sells appliance spare parts across several Shopify stores, almost everything we built lives outside the theme. At Boticasur, an online pharmacy in Málaga running PrestaShop, we moved the store to its own server and added an AI agent and a search engine.

If you need a back-office application rather than a store, see custom software. To cut manual work between the store and your other systems, see AI process automation.

Shopify Partner

Shopify, when it is the right call

We are a Shopify Partner. We set up stores, connect them to your ERP and logistics, and build what Shopify does not ship with, such as shipping rates calculated at checkout or search for large catalogues.

We also publish apps. Ittstocks connects a Shopify store to the ITTStocks warehouse management system: orders go to the warehouse, stock flows back to the store and every shipment is closed with its tracking number. It has been on the Shopify App Store since 7 September 2026, and to get it approved we cut the permissions it requested down to the ones the code actually uses: from 16 to 10.

Tell us about your project See Ittstocks on the Shopify App Store

Shopify, PrestaShop, WooCommerce or custom: when each one pays off

There is no best platform in the abstract. What decides it is the shape of the catalogue, how much the store has to talk to other systems and who will maintain it two years from now.

Option	A good fit if…	Watch out for…
Shopify	You want to sell soon without looking after servers, and a theme plus a few apps covers what you need. Also for several stores or countries.	Plan and apps are monthly costs. With an external payment gateway instead of Shopify Payments there is a transaction fee, from 2% on Basic to 0.2% on Plus, and live third-party shipping rates start on Advanced (Shopify pricing, 14 Sep 2026).
PrestaShop	You want the code and data on your own server with no platform fee, and your back-office system already talks to PrestaShop, like Boticasur's pharmacy software.	Upgrades are on you, and with thousands of products shared hosting falls short. Bots too: at Boticasur, a crawler working through filter combinations left the store unresponsive for hours.
WooCommerce	Your site already runs on WordPress, the catalogue is small and someone on the team knows their way around the admin panel.	Every plugin has a different author, and an update can affect checkout.
Custom	Your model does not fit a platform: customer-specific pricing, configurators, B2B sales with their own rules, or a store that is part of a larger application.	Checkout, taxes, order emails and returns have to be built and maintained. We do not recommend it for getting started.

When custom is the answer, we usually start from Medusa, an open-source commerce engine, with the storefront in Next.js. We have built three small stores this way. The lesson one of them taught us: Medusa stores prices in euros and the Stripe connector multiplies them by 100 when charging. They had been loaded in cents, and the first test charge came out at €1,900 instead of €19. Stripe's test mode caught it, which is what it is there for.

Two stores, from the inside

Both are in production. Where they started, what we built and what took the most work, which is the most useful part when sizing a similar project.

Electrotodo: several Shopify stores and one central catalogue

Appliance spare parts · Shopify Plus

Starting point: Their main store, electrotodo.es, runs on Shopify Plus and mixes their own stock with products from suppliers who ship straight to the customer. They also run specialist stores, such as Top Spares.
What we built: A central dashboard (AppCentral) that pulls products from each source, generates each store's content with AI and publishes it. Around it, AgentBot serves customers on electrotodo.es and top-spares.com, AgentSearch powers search on both, an in-house service calculates shipping at checkout, and AgentPrice compares prices with competitors and suggests changes that a person approves.
What took the most work: Deciding who writes what. On one of the specialist stores, thousands of product pages once went live with the supplier's original text, in Italian, because publishing read the wrong field. Since then only each store's own content gets published, and there are control queries that must return zero. On the main store, our systems only read unless a specific change is requested.

Shopify PlusMulti-storePer-store AI contentShipping calculated at checkout

Boticasur: PrestaShop moved to its own server

Online pharmacy · PrestaShop

Starting point: An online pharmacy in Málaga with around 4,800 active products on PrestaShop 1.7.8, on shared hosting. Catalogue and stock come from Farmatic, its pharmacy management software, and the warehouse system marks orders as shipped with their tracking.
What we built: The store on its own server with the same PrestaShop version, so that only the location changed. The cutover took place on 4 September 2026, from 18:07 to 19:10, with the final database from the old host. On top: AgentSearch as the search engine, an Agentbot that searches with it and adds products to the basket, and product pages completed every night with a description, FAQs and attributes.
What took the most work: The things that only show up with real data. Testing had always used products with photos; with the real database, the 602 active products without a cover photo threw a 500 error because of one template line. Then came speed: with images finally served as WebP, fonts hosted on the store and reCAPTCHA loaded after the page, Lighthouse on mobile went from 57 to 91 on the home page and from 56 to 90 on product pages (5 Sep 2026). When we reran it on 14 September, the home page scored 89.

PrestaShop 1.7.8Server moveFarmatic and WMSLighthouse mobile 57 → 91

How the store connects to your ERP and warehouse

It nearly always comes down to four flows. The first thing we agree on is not the technology but which system owns each piece of data.

Catalogue, prices and stock
From the ERP to the store. At Boticasur, Farmatic sends them through the PrestaShop webservice, and each system uses its own key and permissions: the store's agent can only read.
Orders
From the store to the ERP or warehouse, ideally two ways: the platform's notification (webhook) as it happens and a periodic check, because notifications fail too.
Shipments and tracking
From the warehouse to the store. Boticasur's warehouse system writes tracking and order status into PrestaShop; Ittstocks does the same in Shopify.
Order history
A Shopify gotcha: without the read_all_orders scope, the API only returns orders from the last 60 days, and it does so without an error, as an empty list. We found out through a history import full of zeros.

When two systems write the same data, one ends up overwriting the other. When we moved Boticasur, we deliberately stopped its PIM, because it would have pushed April's staging prices over Farmatic's real ones: the catalogue is re-imported first, then the PIM starts. If your ERP has no API, custom software explains how we read its database without writing to it.

Migrating a store without losing search rankings

A migration loses traffic when URLs change and nobody prepares for it. Boticasur's new store uses URLs with the product ID and the old one did not: around 5,700 addresses known to Google would have returned 404 the next day.

URL inventory

Every URL of the old store, taken from its database, each one assigned its new URL.

301 redirects in a single hop

Straight to the final URL, with https and without www. With the server behind a proxy, the first 301s pointed to http:// and added a hop: the destination has to be absolute.

A rehearsal with real data

A recent copy of production in the new environment, going through the ugly cases too: products without photos, out of stock or with odd names.

A short cutover with a way back

Maintenance mode, final dump, DNS change and tests. The previous database is kept for a few weeks.

After the cutover

Sitemap, Search Console, Bing Webmaster Tools, the Merchant Center feed on the same URL, and patience: for weeks Google holds on to the old URLs and some categories show as crawled but not indexed.

E-commerce FAQs

Shopify or a custom online store?

If Shopify and a few apps cover what you sell and how you sell it, Shopify: it saves you servers, checkout, taxes and upgrades. Custom pays off when your model does not fit the platform or the store is part of a larger application. Often the answer is Shopify with custom work around it, as at Electrotodo.

Can Shopify or PrestaShop be connected to my ERP?

Yes, as long as the ERP lets data in and out somehow: an API, a webservice, files or reading its database. Usually the ERP owns catalogue, prices and stock, and the store owns orders. That gets agreed before writing any code.

How do you migrate an online store without losing SEO?

With a map of every indexed URL to its new address, 301 redirects in a single hop, a rehearsal with real data and monitoring in Search Console afterwards. At Boticasur around 5,700 URLs were redirected on the same day the store changed servers.

What does it mean that Nexttia is a Shopify Partner?

We are part of Shopify's programme for agencies and developers who work for other businesses. We set up stores, build on Shopify and publish apps such as Ittstocks, available on the Shopify App Store since 7 September 2026.

Can you work on the store I already have?

Yes, that is the most common case. Electrotodo's main store already existed when we started: we work around it and our systems only read from it unless a specific change is requested.

Do I need to change platforms to add an AI agent or a search engine?

No. AgentBot and AgentSearch load with a script, on Shopify and PrestaShop alike. That is how they run today on electrotodo.es, top-spares.com and boticasur.es.

Custom e-commerce, on Shopify or PrestaShop