Yersultan - Senior React.js Developer

Demonstrated experience with JavaScript (ES6+).

Demonstrated experience with TypeScript.

Demonstrated experience with Python.

Demonstrated experience with HTML5.

Demonstrated experience with CSS3.

Developing digital products for Sky Bank. Migrated 8 frontend applications into a Turborepo monorepo, centralizing shared libraries and UI components and cutting initial page load time from 2.5-5s to 0.5-1.5s.. Designed and implemented a modular frontend architecture across multiple banking products.. Built and maintained a shared design system based on shadcn/ui, standardizing UI development across all 8 applications.. Optimized API interactions with RTK Query, eliminating redundant network calls through caching and deduplication, and standardized validation using Zod.. Implemented OTP verification and an interactive Leaflet map for region/property selection.. Implemented multilingual support (i18n) across multiple products (RU, UA, EN).. Improved CI/CD pipelines, reducing manual deployment effort and accelerating releases.. Built an auto loan platform from scratch using Next.js and TypeScript, including a multi-step application flow with dynamic step switching based on backend status and a credit calculator visualized with ECharts Gauge Charts.. Integrated external APIs and managed application state with Redux Toolkit.. Conducted code reviews and contributed to frontend development standards.

Optimized SSR and client-side hydration in a Next.js application, reducing initial page load time and improving the user experience.. Developed an employee self-service portal for managing corporate documentation with search, filtering, change history, and version control using React and Redux Toolkit, simplifying document handling for the entire team.. Structured the frontend codebase using Feature-Sliced Design (FSD), improving code organization, scalability, and long-term maintainability.

Participated in building a trading equipment sales platform with React.js and Next.js, contributing to a 2.5x revenue increase in 6 months.. Migrated legacy vanilla JavaScript code to React, improving codebase maintainability and simplifying project scaling.. Optimized SEO and the technical foundation of the websites, increasing organic traffic by 40%.. Refactored the component architecture and extracted reusable logic into custom hooks, reducing code duplication.. Implemented lead-generation forms with automatic submission delivery to the sales team's CRM, eliminating the manual processing step.

Migrated the backend from Laravel to Node.js, speeding up performance and simplifying development.. Developed and maintained the frontend and backend for the e-commerce platforms "Meloman" and "Marwin" — serving a catalog of 200,000+ products and the PRIME loyalty program used by hundreds of thousands of active customers — using Laravel.. Implemented real-time features to enhance user experience.