Hi, I'm Sasa, a Full Stack Web Developer based in Valencia, Spain. I specialize in building SaaS platforms end-to-end, including user authentication, API integration, PDF reporting, and responsive web apps. I love crafting mobile-first interfaces and scalable backends with Next.js, React, and FastAPI. Over the last 3 years, I shipped production platforms serving ~18,000 users, built admin dashboards, AI-powered analysis features, and automated reporting, and I always strive for clean documentation and handover-ready code.

SAŠA PAJIĆ

Hi, I'm Sasa, a Full Stack Web Developer based in Valencia, Spain. I specialize in building SaaS platforms end-to-end, including user authentication, API integration, PDF reporting, and responsive web apps. I love crafting mobile-first interfaces and scalable backends with Next.js, React, and FastAPI. Over the last 3 years, I shipped production platforms serving ~18,000 users, built admin dashboards, AI-powered analysis features, and automated reporting, and I always strive for clean documentation and handover-ready code.

Available to hire

Hi, I’m Sasa, a Full Stack Web Developer based in Valencia, Spain. I specialize in building SaaS platforms end-to-end, including user authentication, API integration, PDF reporting, and responsive web apps. I love crafting mobile-first interfaces and scalable backends with Next.js, React, and FastAPI.

Over the last 3 years, I shipped production platforms serving ~18,000 users, built admin dashboards, AI-powered analysis features, and automated reporting, and I always strive for clean documentation and handover-ready code.

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Experience Level

Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Intermediate
Intermediate
Intermediate
Intermediate
Intermediate
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Work Experience

Full Stack Web Developer at Pragmatic Labs AI
March 1, 2025 - Present
Built and launched a SaaS platform (S.A.F.E.T.Y.™) serving ~18,000 users with user registration, authentication, and role-based access; implemented automated PDF report generation and asynchronous email delivery; optimized database operations and admin dashboards, reducing load times by 95% with sub-5ms query responses; delivered a mobile-first, responsive UI across desktop and mobile with Vite-optimized production bundles.
Full Stack Developer at Totema
May 1, 2024 - February 1, 2025
Built a FastAPI REST API with token-based authentication serving 20 endpoints for AI-powered data processing; integrated third-party AI APIs (OpenAI GPT, Anthropic Claude) via LangChain for document extraction and analysis; designed and developed a data-driven advisory platform enabling recruiters to process hundreds of CVs per cycle.
Web Developer & Designer at Freelance
February 1, 2023 - January 1, 2024
Developed reusable, responsive UI components using HTML, SCSS, TypeScript, and Angular for GitWorks - an open platform for collaborative model-based engineering; built accessible design system components using Angular Material, ensuring consistent user experience across devices.

Education

Bachelor's degree in Computer Science and Automation at Faculty of Technical Sciences, University of Novi Sad
January 1, 2016 - January 1, 2022

Qualifications

Add your qualifications or awards here.

Industry Experience

Software & Internet, Professional Services, Media & Entertainment

Experience Level

Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Intermediate
Intermediate
Intermediate
Intermediate
Intermediate
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