Jan Rzewucki
Frontend Mentor
Experience
Frontend Mentor
TeachMeSkills
- 150 hours of frontend lectures
- Two tracks of lecturing: "HTML & CSS" and "JS Basics"
- More than 30 students overall.
Senior Frontend Engineer
Goldman Sachs
Led solo refactoring and strategic redesign of a core application, ensuring longevity, cost efficiency, and improved business operations.
Led a major uplift of a core monorepo used across the entire GS organisation.
Delivered a new budget planning automation application in two weeks, demonstrating project management and coding skills under pressure.
Directed technical aspects of a central dashboard redesign, ensuring smooth delivery within a 7-day timeframe, showcasing leadership and efficiency.
Mentored developers of all levels, fostering a collaborative learning environment and promoting skill development.
Implemented CI/CD pipelines for frontend projects, ensuring seamless integration, automated testing, and efficient deployment.
Frontend Engineer
Oomnitza
Managed to improve app loading speed by two times by successfully delivering major tech stack improvements.
Provided top-score accessibility of a large application by leading the redesign.
Improved static analysis flow so that all formatting is done and checked automatically.
Regularly mentored junior-to-mid developers.
Managed the tech debt backlog.
Developed new features using React, JavaScript, TypeScript, and Redux.
Frontend Engineer
Net2Phone
Internationalized a large application.
Developed frontend feature flags architecture.
Established static analysis flow from git hooks to CI/CD checks.
Managed the tech debt backlog.
Participated in architecture discussions.
Mentored junior developers.
Developed new features using Angular and TypeScript.
Industries Experience
See where this freelancer has spent most of their professional time. Longer bars indicate deeper hands-on experience, while shorter ones reflect targeted or project-based work.
Experienced in Banking and Finance (4.5 years), Telecommunication (2 years), Information Technology (1 year), and Education (0.5 years).
Business Areas Experience
The graph below provides a cumulative view of the freelancer's experience across multiple business areas, calculated from completed and active engagements. It highlights the areas where the freelancer has most frequently contributed to planning, execution, and delivery of business outcomes.
Experienced in Information Technology (7.5 years) and Project Management (4.5 years).
Summary
Senior Frontend Engineer with seven years of experience. Founder of the best Chess Calendar App out there.
Skills
- Next.js
- React
- Typescript
- Tailwind
- Graphql
- Tanstack-query
- Jotai
- Javascript
- Html5
- Css3
- Sass
- Angular
- Node.js
- Headless Cms
- Redux
- Webpack
- Cra
- Vite
Languages
Education
Belarusian State University of Informatics and Radioelectronics
Bachelors · Minsk, Belarus
Certifications & licenses
Polish B2
Polish State Commission for Polish Language assessments
FCE - Grade A (C1)
Cambridge University Press & Assessment
Profile
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