01Custom software and integrations
New software with AI
When nobody sells what you need, it gets built. Internal applications, customer portals and process tools designed from day one with AI as part of them—not bolted on at the end—on infrastructure that belongs to you.
TypeScript · React · Node · .NET · AWS serverless · Claude
What we do
Internal applications
What you now do with three spreadsheets and an email. A tool that does exactly your process and nothing else.
Customer and supplier portals
Customers look things up, place requests and download on their own, and the AI answers what a person used to answer.
Process tools with AI built in
Classifying, extracting, drafting, deciding: AI as one piece of the workflow, with a person approving where needed.
Digital products
If what you want to build is a product to sell, that too. Sanfeliu has two in production.
What it looks like in practice
- A case file application where every incoming document arrives already classified, with its data extracted.
- A portal where customers track their order and ask questions, and the answer comes from the real data.
- Two products of our own that we use as a lab: taula.ai, reservations for restaurants, and Guestproof, review websites for vacation rentals.
A real example
On a Tuesday afternoon, a shop in Sabadell gets in touch: they want customers to put together their Christmas gift box on the website, and to accept orders from a dashboard.
By Tuesday evening there’s a demo deployed, with orders and PDF invoices that are generated on their own. Wednesday morning, the 3D box with their products. Thursday, the proposal with the fixed price.
Eight days after the first contact, the tool is in production on their own domain, and the improvements that come from using it go in day by day.
It’s path A in How we work: a prototype before the price, a fixed-price proposal and, if they want one, a continuity plan for campaign months only. How we work
What you need
- A problem worth a project, not a screen.
- Someone at the company who owns it and has time to look at progress every week.
- Wanting the code and the accounts to be yours. They will be.
A case
Vacation rental agency
- What was there
- Nearly two thousand verified reviews scattered across about a hundred listings on a portal, invisible to Google and to AI assistants.
- What we did
- A review site of their own in three languages that collects, verifies and publishes them so they can be found and cited.
Who develops custom software with artificial intelligence in Barcelona?
Sanfeliu develops new software for companies—internal applications, customer and supplier portals, process tools, and digital products—designed from day one with artificial intelligence as part of it: sorting, extracting, drafting, or deciding as steps in the workflow, with a person approving where needed. We build in phases, showing working software every week, on cloud infrastructure the client owns, with the code and the accounts in the client’s name.
- Technology: TypeScript, React, Node, .NET, AWS serverless, Claude, and Amazon Bedrock.
- The code, the accounts, and the infrastructure belong to the client from day one.
- Built in phases, with working software delivered every week.
- First step: a free fit session; then an audit with a fixed quote.
- Sanfeliu has its own products in production: taula.ai, reservations for restaurants, and Guestproof, review websites for vacation rentals.
Questions we get asked
- How much does a custom application cost?
- It depends on what it has to do. After the free fit session, the audit ends in a fixed quote for each feature: you choose which ones get built and in what order. Once accepted, the figure doesn’t change.
- How long does it take?
- A first useful version—not a demo—is usually in production within a few weeks, and then it grows in phases. The audit gives the timeline for each phase.
- Who owns the code?
- You do. The repository, the cloud accounts, and the domains are set up in the company’s name. If you ever want to continue with another provider, you can.
- Can we start with something small?
- That is what we recommend: one feature that solves a real problem, in production, and then expand from there. The audit helps you choose where to start.
- What does “designed for AI from day one” mean?
- It means the data is structured so the AI can read and write it, there is a human approval step where needed, and the cost of the AI is measured from the start. Adding AI to an application that wasn’t designed for it usually costs more than rebuilding it properly.
How we work
Let’s start by seeing if we’re a fit.
Eight questions and a call. Free, and we tell you what we think even if the answer is no.
It’s a call with the engineer who would lead the project, not with a salesperson.