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Hi! I’m Matija, a frontend developer with solid experience building clean, responsive, and high-performing web interfaces. I specialize in React, JavaScript, HTML/CSS, and API integration, focusing on clarity, speed, and maintainable code. I take on project-based or part-time work, from debugging and improving existing sites to developing modern one-page websites or functional web apps. My goal is always to deliver efficient solutions that look great and work flawlessly. Whether you need a quick fix, a polished landing page, or a lightweight custom app, I’m available to help you bring your idea to life — reliably, on time, and with attention to detail.…Hi! I’m Matija, a frontend developer with solid experience building clean, responsive, and high-performing web interfaces. I specialize in React, JavaScript, HTML/CSS, and API integration, focusing on clarity, speed, and maintainable code. I take on project-based or part-time work, from debugging and improving existing sites to developing modern one-page websites or functional web apps. My goal is always to deliver efficient solutions that look great and work flawlessly. Whether you need a quick fix, a polished landing page, or a lightweight custom app, I’m available to help you bring your idea to life — reliably, on time, and with attention to detail.

MATIJA KOSMAC

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

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Hi! I’m Matija, a frontend developer with solid experience building clean, responsive, and high-performing web interfaces. I specialize in React, JavaScript, HTML/CSS, and API integration, focusing on clarity, speed, and maintainable code. I take on project-based or part-time work, from debugging and improving existing sites to developing modern one-page websites or functional web apps. My goal is always to deliver efficient solutions that look great and work flawlessly. Whether you need a quick fix, a polished landing page, or a lightweight custom app, I’m available to help you bring your idea to life — reliably, on time, and with attention to detail.…Hi! I’m Matija, a frontend developer with solid experience building clean, responsive, and high-performing web interfaces. I specialize in React, JavaScript, HTML/CSS, and API integration, focusing on clarity, speed, and maintainable code. I take on project-based or part-time work, from debugging and improving existing sites to developing modern one-page websites or functional web apps. My goal is always to deliver efficient solutions that look great and work flawlessly. Whether you need a quick fix, a polished landing page, or a lightweight custom app, I’m available to help you bring your idea to life — reliably, on time, and with attention to detail.

Available to hire

Hi! I’m Matija, a frontend developer with solid experience building clean, responsive, and high-performing web interfaces. I specialize in React, JavaScript, HTML/CSS, and API integration, focusing on clarity, speed, and maintainable code.

I take on project-based or part-time work, from debugging and improving existing sites to developing modern one-page websites or functional web apps. My goal is always to deliver efficient solutions that look great and work flawlessly.

Whether you need a quick fix, a polished landing page, or a lightweight custom app, I’m available to help you bring your idea to life — reliably, on time, and with attention to detail.

Skills

Experience Level

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Language

English

Fluent

Croatian

Fluent

Swedish

Advanced

Work Experience

Frontend Developer at AssaAbloy Global Web

May 1, 2021 - November 3, 2025

Built and maintained React components for AssaAbloy Global websites used by B2B companies. Collaborated within a large Agile Kanban team using JIRA and Slack. Developed with JavaScript, React, TypeScript, CSS, and Styled Components. Implemented components for Adobe AEM OneCMS with bi-weekly releases. Used Git and CI/CD workflows; designs from Figma integrated.