👋

Hello, I'm Charlie Rios. I'm a Senior Full-Stack Software Engineer based in Amsterdam.
I build products end-to-end — from UI architecture to APIs, infra, and production deployments.

About me

I build products end-to-end: from UI architecture and design systems to APIs, infra, and production deployments. I've led frontend teams as Frontend Lead, owned features as a Product Engineer, and shipped across web, mobile, and cloud. Nowadays I'm growing into a native AI developer, building intelligent systems that reach real users.

What I bring: strong product sense · scalable React/TypeScript frontends · full-stack ownership · AI-native tooling

Featured projects

A selection of products and libraries I've designed, built, and shipped — from native macOS apps to npm packages and full-stack web platforms.

CookGPT - Gourmet Plan & Taste

iPhone/iPad native SwiftUI app — browse and edit recipes, plan meals by day or week, generate grocery lists from your schedule, and run step timers with Live Activities on the Lock Screen and Dynamic Island. Your recipes, meal plans, and shopping lists stay on device.

Swift
iOS
iPadOS

Live demo GitHub

Token Bar

Native macOS menu bar app that unifies AI usage across Cursor, OpenAI, Anthropic, and more — track tokens, credits, spend, and burn rate without juggling provider dashboards. Includes Notification Center widgets, usage alerts, and privacy-first credential storage in the Keychain.

Swift
macOS

Live demo GitHub

Pocket Agent

Open-source local AI assistant ecosystem — Python Pocket Node runs LLM routing, tools, memory, and Telegram on your machine; a macOS desktop app bundles the stack; a Cloudflare Worker API and React web UI handle chat, monitor, and settings.

Python
Cloudflare
React
macOS

Live demo GitHub

dropafile

Drop a file. Everyone gets it live. Ephemeral, live-session file sharing on Cloudflare Workers — spin up a room, share a link or QR code, and let connected peers download in real time. WebSocket signaling on the edge; file bytes flow peer-to-peer in the browser.

Cloudflare
Hono
React
TypeScript

Live demo GitHub

Email Signature Editor

Schema-driven email signature builder with a guided template flow, live HTML preview, and one-click copy into Gmail. Import your profile from LinkedIn to pre-fill fields, then customize in the visual template editor.

React
Vite
Tailwind CSS
shadcn/ui

Live demo GitHub

Lizard UI

React component library with shadcn-style primitives and Tailwind-native glass styling — 23 runtime-swappable color themes, light/dark/system modes, and tree-shakeable ESM + CJS builds with full TypeScript declarations.

React
TypeScript
Tailwind CSS
npm

Live demo GitHub

My skills

HTML
CSS
JavaScript
TypeScript
React
Next.js
Node.js
Git
Tailwind
Prisma
MongoDB
Redux
GraphQL
Astro
Express
tRPC
Python
Shadcdn
Framer Motion
Swift

My Experience

Frontend Lead | Product Engineer (React / Next.js)

Timbal AI

Barcelona, Cataluña, España

November 2025 - Present (8 months)

ReactNext.jsTypeScriptAI

Leading frontend development of a core AI product using React and Next.js.
Defining the product's look, feel, and user experience directly in code.
Collaborating with founders to shape product vision and strategy.
Building impactful, high-performance interfaces with autonomy and ownership.

Frontend Lead | Product Engineer (React / Next.js)

Timbal AI

Barcelona, Cataluña, España

November 2025 - Present (8 months)

ReactNext.jsTypeScriptAI

Leading frontend development of a core AI product using React and Next.js.
Defining the product's look, feel, and user experience directly in code.
Collaborating with founders to shape product vision and strategy.
Building impactful, high-performance interfaces with autonomy and ownership.

Development and maintenance of modern web applications using React 19, Node.js 23, React Router v7, React Bootstrap, Vite, and Axios.
Creation and integration of RESTful APIs with CRUD architecture.
Implementation of Server-Side Rendering (SSR) using Next.js and advanced React Router.
Collaboration with multidisciplinary teams to deliver scalable, accessible, and high-performance solutions, applying WebSockets and the latest WCAG accessibility guidelines.

Frontend Lead Developer (React)

Aplicaciones Web Mardo

Mataró, Cataluña, España

November 2024 - November 2025 (1 year 1 month)

React 19Node.jsReact Router v7Next.jsViteAxiosWebSocketsWCAG

Frontend Lead Developer (React)

Aplicaciones Web Mardo

Mataró, Cataluña, España

November 2024 - November 2025 (1 year 1 month)

React 19Node.jsReact Router v7Next.jsViteAxiosWebSocketsWCAG

Development and maintenance of modern web applications using React 19, Node.js 23, React Router v7, React Bootstrap, Vite, and Axios.
Creation and integration of RESTful APIs with CRUD architecture.
Implementation of Server-Side Rendering (SSR) using Next.js and advanced React Router.
Collaboration with multidisciplinary teams to deliver scalable, accessible, and high-performance solutions, applying WebSockets and the latest WCAG accessibility guidelines.

Fullstack Developer & UI/UX Designer

Pixelimperium

Eivissa/Ibiza, Islas Baleares, España

August 2023 - September 2024 (1 year 2 months)

ReactNext.jsTypeScriptNode.jsPythonJavaSolidityEther.jsAWSVercelNetlifyCloudflareSQL

Full-stack development using React, Next.js, TypeScript, Node.js, Python, and Java.
Design and deployment of eCommerce platforms on AWS, Vercel, Netlify, and Cloudflare Pages.
Creation of UI/UX interfaces, custom APIs, and solutions with SQL databases.
Experience in Blockchain and Web3 (Solidity, Ether.js) for decentralized applications.

Fullstack Developer & UI/UX Designer

Pixelimperium

Eivissa/Ibiza, Islas Baleares, España

August 2023 - September 2024 (1 year 2 months)

ReactNext.jsTypeScriptNode.jsPythonJavaSolidityEther.jsAWSVercelNetlifyCloudflareSQL

Full-stack development using React, Next.js, TypeScript, Node.js, Python, and Java.
Design and deployment of eCommerce platforms on AWS, Vercel, Netlify, and Cloudflare Pages.
Creation of UI/UX interfaces, custom APIs, and solutions with SQL databases.
Experience in Blockchain and Web3 (Solidity, Ether.js) for decentralized applications.

Architecting high-performance, accessible web applications with React, Next.js, and TypeScript for robust code quality.
Led development of complex UI/UX interfaces and component libraries, ensuring WCAG accessibility compliance.
Optimized frontend performance and state management by leveraging Vite for rapid bundling and defining efficient RESTful API consumption via Axios.
Implemented WebSockets for real-time data flow, significantly enhancing application responsiveness and user experience.
Managed seamless deployment and hosting of applications on platforms including Vercel, Netlify, and Cloudflare Pages.

Senior Frontend Web Developer

Pixelimperium

Eivissa/Ibiza, Islas Baleares, España

September 2022 - August 2023 (1 year)

ReactNext.jsTypeScriptViteAxiosWebSocketsWCAGVercelNetlifyCloudflare Pages

Senior Frontend Web Developer

Pixelimperium

Eivissa/Ibiza, Islas Baleares, España

September 2022 - August 2023 (1 year)

ReactNext.jsTypeScriptViteAxiosWebSocketsWCAGVercelNetlifyCloudflare Pages

Architecting high-performance, accessible web applications with React, Next.js, and TypeScript for robust code quality.
Led development of complex UI/UX interfaces and component libraries, ensuring WCAG accessibility compliance.
Optimized frontend performance and state management by leveraging Vite for rapid bundling and defining efficient RESTful API consumption via Axios.
Implemented WebSockets for real-time data flow, significantly enhancing application responsiveness and user experience.
Managed seamless deployment and hosting of applications on platforms including Vercel, Netlify, and Cloudflare Pages.

IT Consultant & Web 3.0 / Apps Developer

DR FINANTRUST

Barcelona, Cataluña, España

May 2022 - September 2022 (5 months)

ReactReact NativeNode.jsJavaAWSOracle CloudCloudflareEther.js

Development of trading software for currency and stock markets using React, React Native, Node.js, and Java.
Work with AWS, Oracle Cloud, Cloudflare, and Ether.js to build secure and scalable systems.
Training and mentorship of the junior team, improving productivity and adoption of internal tools.

IT Consultant & Web 3.0 / Apps Developer

DR FINANTRUST

Barcelona, Cataluña, España

May 2022 - September 2022 (5 months)

ReactReact NativeNode.jsJavaAWSOracle CloudCloudflareEther.js

Development of trading software for currency and stock markets using React, React Native, Node.js, and Java.
Work with AWS, Oracle Cloud, Cloudflare, and Ether.js to build secure and scalable systems.
Training and mentorship of the junior team, improving productivity and adoption of internal tools.

Responsible for a 5-person IT team, managing client applications, websites, and systems using React, Angular, Node.js, PHP, Java, and Swift.
Delivery of B2B solutions, strengthening client relationships and generating add-on sales for IT services.
Full-stack development and management within cloud environments (AWS).

IT Consultant & Web Developer

Businessprinter, S.L.

Barcelona, Cataluña, España

November 2020 - May 2022 (1 year 7 months)

ReactAngularNode.jsPHPJavaSwiftAWS

IT Consultant & Web Developer

Businessprinter, S.L.

Barcelona, Cataluña, España

November 2020 - May 2022 (1 year 7 months)

ReactAngularNode.jsPHPJavaSwiftAWS

Responsible for a 5-person IT team, managing client applications, websites, and systems using React, Angular, Node.js, PHP, Java, and Swift.
Delivery of B2B solutions, strengthening client relationships and generating add-on sales for IT services.
Full-stack development and management within cloud environments (AWS).

Web Developer (Junior)

Businessprinter, S.L.

Barcelona, Cataluña, España

June 2020 - November 2020 (6 months)

ReactAngularNode.jsPHPJavaSwiftAWS

Assisted in the development of client websites and applications using React, Angular, and Node.js under the guidance of senior developers.
Focused on front-end feature implementation and bug resolution, contributing to the deployment of new B2B solutions.
Maintained and updated legacy code in PHP, Java, and Swift to ensure system stability and cross-platform compatibility.
Gained foundational experience in full-stack development principles and contributed to basic cloud environment tasks on AWS.

Web Developer (Junior)

Businessprinter, S.L.

Barcelona, Cataluña, España

June 2020 - November 2020 (6 months)

ReactAngularNode.jsPHPJavaSwiftAWS

Assisted in the development of client websites and applications using React, Angular, and Node.js under the guidance of senior developers.
Focused on front-end feature implementation and bug resolution, contributing to the deployment of new B2B solutions.
Maintained and updated legacy code in PHP, Java, and Swift to ensure system stability and cross-platform compatibility.
Gained foundational experience in full-stack development principles and contributed to basic cloud environment tasks on AWS.

Development and maintenance of websites, evolving toward React with strong foundations in JavaScript, HTML/CSS, and SQL.

Software Engineer (Junior)

Magnum Object, S.L.

Cornellà de Llobregat, Cataluña, España

July 2018 - June 2020 (2 years)

ReactJavaScriptHTMLCSSSQL

Software Engineer (Junior)

Magnum Object, S.L.

Cornellà de Llobregat, Cataluña, España

July 2018 - June 2020 (2 years)

ReactJavaScriptHTMLCSSSQL

Development and maintenance of websites, evolving toward React with strong foundations in JavaScript, HTML/CSS, and SQL.

Systems & Networks Admin

Magnum Object, S.L.

Cornellà de Llobregat, Cataluña, España

August 2017 - July 2018 (1 year)

WindowsmacOSLinuxSAPNetworking

Comprehensive IT department support: system configuration, server/network management, hardware maintenance, SAP and RMA.
Multi-platform support (Windows, macOS, Linux) for B2B clients.

Systems & Networks Admin

Magnum Object, S.L.

Cornellà de Llobregat, Cataluña, España

August 2017 - July 2018 (1 year)

WindowsmacOSLinuxSAPNetworking

Comprehensive IT department support: system configuration, server/network management, hardware maintenance, SAP and RMA.
Multi-platform support (Windows, macOS, Linux) for B2B clients.