Denis Marushchak

Denis Marushchak

Front End Developer & Designer

About

As a Frontend Developer and UI Designer with 6 years of experience, I specialize in building complex, dynamic React applications and have experience with real-time features, drag-and-drop interfaces, and design systems.

I work with React, TypeScript, and frameworks like Next.js, Remix, and Astro. I've worked on No-Code application builders with real-time collaboration, event management systems, and design systems. I also create marketing websites powered by headless CMSes such as PayloadCMS and WordPress.

My portfolio includes drag-and-drop interfaces with WebSocket integration, design systems that bridge Figma and code, and internal tools that improve team workflows.
I'm passionate about web technology and build AI-powered side projects in my free time.

Work Experience

6+ years
2024 — Now
Remote
ReactTypeScriptAIRemixFeathers.jsWebSocketsMobXZustandTurborepoPlaywrightJestSWRRollup
Working on two primary projects:

Lead developer for a No-Code Web Application Builder platform (pre-release). Designed and built the core functionality including:

• Advanced drag-and-drop component system with nested container support
• Metadata management system for component properties and styling
• Dynamic page creation and routing system
• Custom component library with state management integration
• Real-time preview and publishing workflow using WebSockets and Feathers.js
• Real-time collaboration features with conflict resolution
• AI-assisted component and whole section generation

Contributed to Puck Editor, an open-source visual editor for React, while developing the drag-and-drop functionality for the application builder.

Contributing developer on Kvarum, an event scheduling service, focusing on UX improvements and feature implementation.
2020 — 2025
Talinn, Estonia
ReactTypeScriptAWSFigmaDesign SystemGatsbyNext.jsAstroPayloadCMSWordPressTailwindCypressPHPJest
Early years focused on building custom WordPress themes and internal plugins, including tools for tracking 404 errors, identifying broken/missing links, and managing reusable content templates.

• Transitioned into designing and developing marketing websites using headless WordPress, Gatsby, and Next.js — handled everything from design in Figma to frontend development and CMS setup.
• Created and maintained the company's internal wiki platform from scratch using Next.js (without templates), including layout, architecture, and component system.
• Led the development of an internal design system — contributed to both Figma libraries and React implementation, introducing scalable patterns and reusable components.

Contributed to several enterprise tools:
• Service and POS applications
• Scheduling tracker for employees
• Other ERP-related internal apps and utilities
2019 — 2020
Auckland, New Zealand
ReactStorybookDesign SystemComponent LibraryUI DevelopmentFigmaCSS
• Worked on internal event management tool for the admin team
• Maintained internal React UI Kit and component libraries
• Designed new component patterns and contributed to UX decisions
• Worked across both frontend dev and product/visual design
2019 — Present
Frontend Developer / UI Engineer at Freelance
Remote
ReactTypeScriptNext.jsAstroPayloadCMSSCSSTailwindStyled ComponentsFigmaFramer MotionAI
Delivered custom web solutions for clients like Hours.ee, Shoproller.com, PDFGenerator, and more.
Working across development and UI/UX design

Education

2018 — 2020
Diploma In Software Development at Cornell Institute of Business & Technology
Auckland, New Zealand

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