Experience | Roman Onishchenko

Experience

Professional experience shaped by frontend depth and full-stack delivery

A curated view of roles, responsibilities, and engineering work across product development, maintainable architecture, and production-ready systems.

Improved codebase maintainability by aligning implementation with modern best practices and clean architecture principles
Developed UI components and migrated legacy forms to a Figma-based design system
Introduced and configured code quality tools (ESLint, Prettier, Husky), improving consistency and developer experience
Built and extended frontend features using React and Redux Toolkit, with a focus on maintainability and testability
Improved data fetching strategy by introducing React Query, reducing backend load through caching and query invalidation
Participated in system architecture and technical decisions across frontend and backend
Integrated AWS services (e.g., S3, EC2) into application development and deployment workflows
Increased system reliability by adding test coverage for critical application flows

Developed and maintained a CMS platform for data collection and analysis
Refactored legacy React/JavaScript code, improving maintainability
Built reusable UI components, reducing duplication and speeding up feature delivery
Improved code quality through refactoring

Developed and maintained a web-based reading platform, focused on usability and performance of content-heavy pages
Built and maintained frontend features using React and TypeScript, improving user experience and functionality of the application
Optimized rendering and interaction patterns for a smoother reading experience across devices
Wrote unit tests and performed manual testing to ensure stability of core user flows
Contributed to ongoing improvements of code quality and maintainability within the frontend codebase

Worked on complex product features, frontend quality improvements, and system evolution in a collaborative engineering environment.

Developed and maintained a fundraising platform used for managing donation flows and user interactions
Improved stability of a legacy React/TypeScript codebase and extended existing functionality
Implemented UI enhancements, improving usability and overall consistency of the application
Performed minor backend updates in Python to support feature delivery

Developed and maintained company websites and product landing pages, supporting multiple software products and marketing initiatives
Built frontend functionality using JavaScript and jQuery, including development of custom plugins to extend UI behavior
Contributed to backend development using PHP and MySQL, supporting data-driven features and integrations
Improved maintainability of legacy code by refactoring existing implementations and introducing more structured approaches
Collaborated with design and marketing teams to deliver user-facing features aligned with business goals