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Hi, I’m Josef Žemlička, a Full-Stack Developer with 3+ years of experience building scalable web applications in PHP, React, and TypeScript. I love automating workflows, boosting performance, and turning ideas into production-grade software. I’m starting an MSc in Information Security at Stockholm University in September 2025. I’ve delivered across EU clients, collaborated in agile teams, and earned a 1st place in the 2022 Chamelearn Hackathon.…Hi, I’m Josef Žemlička, a Full-Stack Developer with 3+ years of experience building scalable web applications in PHP, React, and TypeScript. I love automating workflows, boosting performance, and turning ideas into production-grade software. I’m starting an MSc in Information Security at Stockholm University in September 2025. I’ve delivered across EU clients, collaborated in agile teams, and earned a 1st place in the 2022 Chamelearn Hackathon.

Josef Žemlička

Full Stack Developer, Web Developer, Programmer, +1

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Hi, I’m Josef Žemlička, a Full-Stack Developer with 3+ years of experience building scalable web applications in PHP, React, and TypeScript. I love automating workflows, boosting performance, and turning ideas into production-grade software. I’m starting an MSc in Information Security at Stockholm University in September 2025. I’ve delivered across EU clients, collaborated in agile teams, and earned a 1st place in the 2022 Chamelearn Hackathon.…Hi, I’m Josef Žemlička, a Full-Stack Developer with 3+ years of experience building scalable web applications in PHP, React, and TypeScript. I love automating workflows, boosting performance, and turning ideas into production-grade software. I’m starting an MSc in Information Security at Stockholm University in September 2025. I’ve delivered across EU clients, collaborated in agile teams, and earned a 1st place in the 2022 Chamelearn Hackathon.

Available to hire

Hi, I’m Josef Žemlička, a Full-Stack Developer with 3+ years of experience building scalable web applications in PHP, React, and TypeScript. I love automating workflows, boosting performance, and turning ideas into production-grade software.

I’m starting an MSc in Information Security at Stockholm University in September 2025. I’ve delivered across EU clients, collaborated in agile teams, and earned a 1st place in the 2022 Chamelearn Hackathon.

Skills

Experience Level

Expert

Expert

Expert

Expert

Expert

Intermediate

Intermediate

Intermediate

Intermediate

Language

English

Advanced

Work Experience

Software Developer Intern at Carelli

August 1, 2024 - October 2, 2025

Modernized customs software across EU clients: migrated JS to TypeScript. Built accessible, country-specific React components. Collaborated daily in Agile sprints with cross-functional teams (React, Jest, TypeScript, Python (Flask), Azure). Automated multilingual content with DeepL API, cutting manual work by 50%. Boosted website performance by ~40% using caching & query optimization. Created internal tools via Zendesk API, raising business team productivity by 15%. Built a shoppable images feature with hover-activated product details and navigation. Tech stack included PHP, JavaScript, HTML/CSS; used Bitbucket and Jira.