Description

Hello, I’m Sergio Balaguer, a Freelance Fullstack Developer based on Barcelona.

I’m passionate about building scalable, high-quality web applications. By following principles like Clean Code and Clean Architecture, I deliver solutions that are maintainable, modular, and built to last.

What can I bring to the table?

Backend: Secure and optimized APIs developed with Node.js and Express.

Frontend: Modern, dynamic, and responsive user interfaces crafted with React.

TypeScript: Robust, clean, and maintainable code as a standard.

Infrastructure: Scalable environments orchestrated with Docker, ready for high availability.

Integrations: Tailored solutions integrating with services like S3, Redsys, or Brevo.

I’m confident my focus on best development practices can add value to your current or future projects. If you’re working on something exciting or have an idea in mind, let’s connect and explore how I can help.

Looking forward to hearing from you!

Best regards,

Sergio Balaguer

Languages

Spanish
Native or bilingual
Catalan
Native or bilingual
English
Fluent

Workplace preferences

Remote only

Primarily works remotely

Inetum
Frontend Developer
March 2025 - July 2025 (4 months)
I led the acceleration of the first phase of the Plataforma d’Usuaris de les Aigües frontend application for Gencat’s Centre de Telecomunicacions i Tecnologies de la Informació (CTTI), ensuring alignment with the company's architectural guidelines.

The platform is structured into three independent frontend applications forming a unified portal:
- Admin: Manages administrative features such as inviting users to the employee
portal or managing role assignments.
- Employee: Supports internal operations like water-point management and citizen
portal invitations.
- Citizen: Provides access for citizens to view and, depending on permissions, update
water-point information.

One of the most notable features is an interactive map powered by MapLibre,
displaying geospatial elements across different layers, filtered through a hierarchical tree-based interface.
React.js Typescript Jest Clean Architecture Clean Code
Escenit
Fullstack Developer
September 2024 - December 2024 (3 months)
I worked on the new Cementos Molins website, focusing on refactoring legacy application features and integrating them into a modern and scalable application.

I contributed across both frontend and backend in order to achieve my sprint goals.
PHP 8 Angular Symfony
Manuel Fdez.
Frontend Developer
June 2024 - September 2024 (3 months)
I created an scalable frontend app architecture which is designed for managing generically api request states, modals, toasts and route permissions, visualizing PDF and rendering a generic view for lists and details. The project is tested, covered at 100%.

That architecture was used to create two applications:
FacturApp: An invoice Facturae compliant generator
GestionGranjas: A farm animals manager. It’s designed to be used on daily work gathering inputs from a RFID reader in order to track different actions such as assist births, report casualties and apply healthcare treatment.
React.js Clean Code Clean Architecture Domain Driven Design Typescript