In progress
Programmer technician
ZSE Starogard Gdański, technical secondary school
- Also taking the IT technician vocational qualification course (KKZ) at the same school.
Mateusz Muszarski
Full-stack product engineer
Open to full-time and contract roles · remote or hybrid
Profile
Full-stack product engineer who builds web and mobile products end to end, from the business problem to the shipped app, since 2022. I work in TypeScript, React, Next.js, Astro, React Native (Expo), Node.js and Supabase/Postgres. I use AI agents (Claude Code) as leverage and keep the decisions and the verification: tests, accessibility and performance checks on every change.
Experience
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Intern, Cetuspro
June 2026 – now
Software house, remote
- Real commercial projects; built the public configurator of PstrykWeb, the online order form (Next.js, TypeScript, Vercel).
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Intern, Neoteric
2026 · 6 weeks
Software house, Poland
- Built Clockful, a role-based time tracker, with AI agents only, from a spec of 15 requirements in about 9 days (an estimate from the repo dates).
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Intern, KS Beniaminek 03
2025 · 1 month
Sports club
- Social projects at a sports club: work with people, communication and teamwork.
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Freelance and own projects
Since 2022
- Landing pages for businesses and organisations, such as a 3D site for Youth Work Synergy, a youth housing nonprofit in Luxembourg (React, React Three Fiber, GSAP).
- A mobile app for a local youth space; the principal of my technical secondary school gave me an award for it.
Selected projects
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2026
PstrykWeb
In collaboration with Cetuspro
- Bespoke websites for local businesses, ordered through one online form.
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2026
Linkoglot
Own product, founder and developer
- Designed, built and shipped an AI language-learning app to the App Store and Google Play, solo: snap a photo to get flashcards, quizzes and voice practice.
- Free trial, then monthly or yearly plans through RevenueCat; 30 languages with Lingui (Expo, React Native, Supabase).
App Store (opens in a new tab) Google Play (opens in a new tab)
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2026
Portfolio
- Astro, React and Lingui (en/pl/es); Lighthouse mobile 99–100, about 8 KB of JavaScript; built with a Claude Code setup: a project wiki, hooks and skills.
Skills and qualifications
Soft skills
- Teamwork and clients Software houses, hackathon teams
- Problem solving From business problem to shipped app
- Business thinking Solutions measured by business results
- Conversions and UX How people notice, trust and act
- User psychology Consumer psychology and UX courses
- Analytical thinking Marketing planned around goals and data
Technologies
- Web
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- TypeScript
- React
- Next.js
- Astro
- Tailwind CSS
- shadcn/ui
- WebGL
- Mobile
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- React Native
- Expo
- Back end and data
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- Node.js
- Supabase
- PostgreSQL
- TanStack Query
- Quality and UX
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- Playwright E2E testing
- Lighthouse MCP
- Mobbin
- AI and workflow
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- Claude Code
- GitHub
- GitLab
- Vercel API
Qualifications and training
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2024
INF.03 · Polish state vocational exams (CKE / OKE)
Websites, web applications and databases.
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2026
Hackathons · Team events
HackYeah 2026 in Kraków, Europe's biggest on-site hackathon; Hack4Change 2026 in Gdańsk, 48 hours for the Baltic Sea; Product Challenge 2026: Vibe the Future in Rzeszów.
Made me better at working under time pressure and in a team.
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2024–2025
International youth projects · Erasmus+, European Solidarity Corps, Visegrad Fund
Digital youth work in Latvia, youth entrepreneurship in Lithuania, alternative youth participation in Bakuriani (Georgia), two months with sea turtles in Demre (Türkiye).
Made me fluent in communicating with people, especially in English.
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2025
Three.js Journey (opens in a new tab) · Course by Bruno Simon
90+ hours of video and challenges: WebGL with three.js, GLSL shaders, physics, Blender models, post-processing, performance and React Three Fiber.
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2023
Full-stack development courses · Courses by Jonas Schmedtmann, Udemy
Education
Languages
- Polish: native
- English: fluent
Interests
Calisthenics, travel, motorcycles, films, music of every kind, gaming with friends.