Mateusz
Miszczak
Frontend Engineer building production fintech in React and Next.js. Realtime trading interfaces, multi-step financial flows and admin systems.
Bitcoin
End-to-end flows delivered in trading, withdrawals, tax, onboarding and account lifecycle
Live portfolio, order and operation states synchronized without manual refresh
CI/CD pipelines and Terraform-managed frontend infrastructure on AWS
Next.js and Strapi sites in any number of languages, sharing one consent and analytics package
Case Studies
Selected work
Key production areas I worked on across fintech applications, delivery and infrastructure, and CMS-driven websites.
Technical Focus
Technical focus
The technologies, patterns and tools I use every day.
Frontend Architecture
Component-driven React and Next.js apps with TypeScript, App Router and a scalable module structure.
Data and State
Redux Toolkit for UI state, React Query for server data, REST and GraphQL API integrations.
Realtime Systems
Event-driven interfaces and state synchronization using WebSockets.
UI, CMS and Delivery
Responsive layouts, CMS-managed content, analytics, SEO fundamentals and production-ready pages.
My Journey
From freelance work to production fintech
I started with client websites, photography portfolios and data tools, then joined a production fintech team. My scope has grown from single features to owning larger areas end to end, from trading interfaces and withdrawal flows to the CI/CD and frontend infrastructure behind them.
Freelance and commercial projects
Responsive websites for clients and agencies, including a photographer's portfolio scoring 99/100 Performance and 100/100 SEO in Lighthouse, plus marketing sites and data tools.
Production fintech applications
Trading interfaces, wallet views, withdrawal flows, admin systems and WebSocket data synchronization.
Broader scope and ownership
Owning larger features end-to-end: multi-step flows, realtime UI, CI/CD pipelines and frontend infrastructure work.