Hi, I'm Sergi

I build web applications focusing on performance, clean code, and developer-friendly architectures.

Featured Projects

Fintreo

Screenshot of Fintreo app

A personal finance app with real-time sync and secure authentication. Built with a modular, type-safe architecture and responsive UI.

Next.jsTypeScriptFirebaseTailwind CSS

Design System

Screenshot of Design System Storybook

A reusable component library with accessible React primitives and design tokens. Makes it easy to build consistent, flexible UIs across projects.

ReactTypeScriptStorybookAccessibility

3Good

Screenshot of 3Good app

A privacy-first app for daily gratitude. Record three things you’re grateful for, track your streaks, and reflect on your progress with a simple, distraction-free interface.

ReactTypeScriptVitePrivacy

SiteBlockr

Screenshot of SiteBlockr extension

A Chrome extension for privacy-conscious browsing. Lets users control site access while keeping memory and CPU usage minimal.

Chrome APIsTypeScriptPrivacyPerformance

Retro Portfolio

Screenshot of Retro Portfolio website

My old portfolio reimagined with retro aesthetics, built using pure HTML, CSS, BEM, and JavaScript. Showcases past projects.

HTMLCSSJavaScriptBEM

Technical Expertise

Core Front-End

  • JavaScript (ES6+)
  • TypeScript
  • React
  • Next.js
  • HTML5 & CSS3
  • Responsive Design

Architecture & Performance

  • Modular Architecture
  • Component Libraries
  • Design Systems & UI Patterns
  • Code Splitting & Lazy Loading
  • Performance Optimization
  • State Management (Redux)

Quality & Tooling

  • CI/CD
  • Testing (Jest, Cypress)
  • Web Accessibility
  • Build Tools: Webpack / Vite
  • APIs: REST / GraphQL
  • Code Quality: ESLint / Prettier

Latest Writing

Predictability beats specificity when writing CSS.

cssarchitectureprinciples
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Exploring the promise and the hidden costs of micro-frontends.

architecture
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Get in Touch

I’m based in Barcelona 🇪🇸 and open to remote collaboration.