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I'm a passionate Full-Stack Developer with +3 years of hands-on experience building modern web applications. I specialize in Next.js, TypeScript, Node.js, and Web3, delivering responsive, scalable solutions for client and partner projects. I value people over processes, collaborate well in cross-functional teams, and welcome feedback to continuously improve. I'm open to learning new technologies and applying best practices to help teams grow.…I'm a passionate Full-Stack Developer with +3 years of hands-on experience building modern web applications. I specialize in Next.js, TypeScript, Node.js, and Web3, delivering responsive, scalable solutions for client and partner projects. I value people over processes, collaborate well in cross-functional teams, and welcome feedback to continuously improve. I'm open to learning new technologies and applying best practices to help teams grow.

Marc Toni Mas

Full Stack Developer, Back-End Developer, Front-End Developer, +3

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I'm a passionate Full-Stack Developer with +3 years of hands-on experience building modern web applications. I specialize in Next.js, TypeScript, Node.js, and Web3, delivering responsive, scalable solutions for client and partner projects. I value people over processes, collaborate well in cross-functional teams, and welcome feedback to continuously improve. I'm open to learning new technologies and applying best practices to help teams grow.…I'm a passionate Full-Stack Developer with +3 years of hands-on experience building modern web applications. I specialize in Next.js, TypeScript, Node.js, and Web3, delivering responsive, scalable solutions for client and partner projects. I value people over processes, collaborate well in cross-functional teams, and welcome feedback to continuously improve. I'm open to learning new technologies and applying best practices to help teams grow.

Available to hire

I’m a passionate Full-Stack Developer with +3 years of hands-on experience building modern web applications. I specialize in Next.js, TypeScript, Node.js, and Web3, delivering responsive, scalable solutions for client and partner projects.

I value people over processes, collaborate well in cross-functional teams, and welcome feedback to continuously improve. I’m open to learning new technologies and applying best practices to help teams grow.

Skills

Experience Level

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Intermediate

Intermediate

Intermediate

Intermediate

Intermediate

Language

Spanish; Castilian

Fluent

Catalan; Valencian

Fluent

English

Advanced

German

Beginner

Work Experience

Full-Stack Developer at FREELANCE

November 1, 2024 - Present

Built several fully functional web applications for personal and client projects, integrating AI-powered features and working on both front-end and back-end functionality. Delivered client web applications using React, Next.js, and Node.js, focusing on responsive design and cross-browser compatibility. Developed full-stack solutions from requirements gathering to deployment, implementing RESTful APIs, PostgreSQL databases, and Docker containerization. Built blockchain-enabled applications with smart contract integration and wallet connectivity using Ethereum and Metamask. Collaborated with clients to determine requirements, propose solutions, and feedback iterations to ensure satisfaction. Continuously learned and applied new technologies and best practices, staying up-to-date with the latest trends in web development.

Software Lead & Solar Innovation at EFIWATT

November 1, 2024 - September 5, 2025

Led development of custom JavaScript applications that increased team productivity by 60% through workflow automation. Architected and implemented data pipelines integrating multiple APIs to automate reporting processes for 200+ solar projects. Designed and implemented database solutions for solar project data management and retrieval. Enhanced solar design software, streamlining workflows and improving user experience. Managed cross-functional technical projects, ensuring on-time delivery while mentoring junior technicians. Created data visualization dashboards using Excel, Power BI, and TypeScript to drive data-informed decision making.