SANFELIU
Custom software on AWS for companies that already run systems: applications, integrations and automations, plus a monthly plan to keep it running.
Barcelona · software engineer
Joan Sanfeliu Vilarrasa
Founder of SANFELIU, a studio building custom software on AWS. I build my own products and teach others to build theirs.
Most companies I talk to do not need artificial intelligence. They need the software they already pay for every month to actually be useful.
01The problem
It is almost always the same.
A CRM nobody fills in, three tools that do not talk to each other, a fifteen-year-old ERP, and someone on the team losing two hours a day copying data from one place to another. And this year, on top of that, the pressure to “do something with AI”.
I go and look first.
Sometimes you need real AI, and then we build it. Sometimes connecting two tools you already have is enough and the problem goes away. And sometimes the right thing is to tell you that you do not need it, which is the conversation I least like having and the one that saves you the most.
At SANFELIU, the studio I founded, we do three things:
02How I work
Three rules and six steps.
- 1
Fixed price per feature, never by the hour.
- 2
The first conversation is free.
- 3
If I cannot help you, I tell you on that same call.
The process
The full process, at SANFELIU- 01FitA call or a visit: what is going wrong, what you already have and what must not change.
- 02PrototypeA working demo with your own data, within one to three days and before any talk of price.
- 03ProposalA document with screenshots of your demo and a fixed price per feature.
- 04ProjectIn short phases, over weeks, with a real delivery at the end of each one.
- 05HandoverA handover record, the code in your name and the first month of minor changes included.
- 06ContinuityA support plan with no lock-in, or none.
03Why you can believe me
I build it, pay for it and fix it myself.
I spend half my time building my own software, in production on AWS (today, taula.ai, Guestproof and Canasta), which I pay for and fix myself when it breaks. The other half, inside small and mid-sized companies that already run their own software and need someone who really understands it. And, since 2023, I have taught frontend development at TecnoCampus in Mataró.
I have ten years of engineering experience and have worked for Allianz Direct, NTT Data and MONEI, among others. I held the AWS Solutions Architect Associate and Cloud Practitioner certifications (2022–2025), and I am an advisor accredited by ACCIÓ, the Catalan Government’s business agency. That means I know ACCIÓ’s funding programmes for SMEs and, when one that fits your project is open, I’ll tell you.
04The three branches
The studio, the products and the teaching.
Three things, each in its place. Go in through the one that fits.
Products
My own products, in production.
Teaching
Frontend classes at TecnoCampus in Mataró, notes and courses in Catalan at formacio.joansanfeliu.com, and AI workshops for schools.
05Right now
What is in progress.
Dated, so it can be checked.
- September 2026
taula.ai, bookings for restaurants: in production, with real restaurants. taula.ai
- September 2026
Guestproof, review websites for vacation rentals built from Airbnb, Booking and Vrbo reviews: in production. getguestproof.com
- September 2026
At the studio: the four-language website of a group of three hotels in Cerdanya and Porto, in production; integrations and a management dashboard for a logistics software company, ongoing. sanfeliusoftware.com/casos
- September 2026
Development classes at TecnoCampus in Mataró, two evenings a week, and AI workshops for schools for the 2026-27 school year. formacio.joansanfeliu.com/escoles
Latest articles
From the blog, in Catalan, at formacio.joansanfeliu.com. All articles
El correu l'havia escrit una IA: l'entrevista d'un estudi universitari, resposta a respostaUna investigadora m'ha entrevistat per a un estudi sobre com decidim els fundadors. El correu l'havia enviat una IA. Les preguntes i el que hi vaig respondre.
On hi posem la IA i on no: l'alta de taula.ai per dinsL'alta de taula.ai per dins: on fa feina la IA, on no n'hi deixem fer i per què. Amb el diagrama de l'arquitectura i el vídeo.
M'han trobat per ChatGPT: què diuen els registres de la webUn propietari d'un pis turístic em va trobar preguntant a ChatGPT. Als registres d'accés es veu la visita, quins robots d'OpenAI llegeixen la web de debò i quins se'n fan passar per buscar contrasenyes.
06Career
One line per stage.
In short
Joan Sanfeliu Vilarrasa is a software engineer based in Barcelona and the founder of SANFELIU, which builds custom software on AWS for companies that already run their own systems. He has three products in production, taula.ai (restaurant bookings), Guestproof (review websites for vacation rentals) and Canasta (the card game, online and free), and teaches frontend development at TecnoCampus in Mataró. He has ten years of engineering experience and has worked for Allianz Direct, NTT Data and MONEI, among others.
Certifications and accreditations
- AWS Solutions Architect Associate and Cloud Practitioner certifications (2022–2025)
- Advisor accredited by ACCIÓ (Catalan Government)
- 2026 – present
SANFELIU · Founder. Custom software on AWS, Barcelona.
- 2023–2026
MONEI · Senior full-stack engineer. Payments platform.
- 2023
Bloome · Full-stack engineer. Sole engineer on two production applications.
- 2021–2023
NTT Data · Solutions analyst: frontend and data.
- 2020–2021
Wepelopers · Co-founder and lead engineer. Web agency for small businesses.
- —
Allianz Direct · Software engineering projects.
Companies and projects I have worked on
07Contact
If you plan to change something in your software this year and want the opinion of someone who builds software every day, write to me.
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