Sebastian Kolbusz
Senior Frontend Engineer
Professional Summary
Senior Frontend Engineer with 6+ years of experience specialized in building high-performance SaaS products using React, TypeScript, and GraphQL. Expert in architectural optimization, having successfully reduced enterprise application bundle sizes by 50%. Proven track record in leading feature development from discovery to deployment, prioritizing developer experience (DX), scalability, and robust automated testing.
Professional Experience
Ready2Order
08/2019 – 12/2025Senior Frontend EngineerVienna (Remote)
Engineered and scaled a market-leading POS system serving 10,000+ European businesses.
- Reduced React application bundle size by 50%, significantly improving TTFB and user retention
- Architected and delivered the CashBook module using React, Apollo GraphQL, and TailwindCSS
- Optimized legacy backend APIs (PHP/MySQL) to support high-throughput frontend features
- Established engineering standards through comprehensive code reviews and mentoring
- Implemented enterprise-grade testing strategies using Jest, RTL, and Cypress
- Drove agile product cycles within a high-performance Scrum environment
Freelance Architect
2016 – PresentFrontend ConsultantZakopane, Poland
Delivering premium digital assets and technical strategy for international clients.
- Launched high-conversion platforms (zakofy.com, yourkrakowtravel.com) resulting in 400% organic traffic growth
- Developed interactive 3D and GSAP-powered experiences for premium lifestyle brands
- Engineered custom booking systems and search components specialized for the tourism sector
- Consulted on UX strategy and technical architecture for early-stage startups
Academic Background
University Of Economics
09/2016 – 09/2019Software Engineering | Bachelor in Applied InformaticsCracow
- Science-IT Club Member (KNI)
- Author of KNI Club website in years 2016-2019