Contact information

You can get this candidate's contact information from https://www.work.ua/resumes/6973043/

Work experience

Front-end програміст

from 05.2020 to 08.2026 (6 years 4 months)
Unicsoft (IT)

Additional information

CV

**Osypenko Kostyantyn Serhiiovych**

Schedule: Full-time, Remote
Phone: [open contact info](look above in the "contact info" section)
E-mail: [open contact info](look above in the "contact info" section)
LinkedIn: [open contact info](look above in the "contact info" section)

**Professional Summary**

Senior Frontend Developer with 6 years of commercial experience building complex web and mobile applications. Specialized in React, TypeScript, fintech platforms, data-intensive interfaces, role-based access control, and frontend performance optimization. Experienced in frontend architecture, API integrations, security-sensitive workflows, and end-to-end product development.

**Education**

2019 — 2023
Vinnytsia National Technical University
Bachelor's Degree in Computer Science

2023 — 2025
Vinnytsia National Technical University
Master's Degree in Computer Science

**Technical Experience**

2021 — 2026
Unicsoft / Helpware.tech
Software Developer (Frontend / Full-stack)

- Developed React, Vue.js, and Nuxt applications for fintech and business platforms.
- Built complex administrative systems with CRM, wallet management, transaction monitoring, financial dashboards, and compliance workflows.
- Designed configurable role-based access control (RBAC) with granular permissions and dynamic navigation.
- Developed financial reporting interfaces with advanced filtering, aggregations, calculations, and CSV/Excel exports.
- Implemented KYC/AML workflows, secure authentication, two-factor authentication, and approval processes.
- Integrated internal and third-party REST APIs.
- Developed reusable UI components, drag-and-drop interfaces, rich text editors, and interactive experiences.
- Improved onboarding UX, contributing to a 30% increase in completed registrations and purchases.
- Optimized frontend performance, caching, and SEO.
- Modernized frontend tooling using Vite and TypeScript, reducing build time from 5 minutes to 1 minute.
- Participated in code reviews, mentoring, CI/CD, and production troubleshooting.
- Contributed to a React Native fintech application with wallet, payment card, trading, and authentication features.

05.2020 — 04.2021
Upwork
Frontend / Full-stack Developer

- Developed web applications using Vue.js, Nuxt.js, JavaScript, and Node.js.
- Implemented responsive interfaces, REST APIs, authentication, and database integrations.
- Managed application development from requirements analysis to deployment.
- Optimized application performance, improving content rendering time by approximately 2 seconds.
- Delivered SEO improvements and resolved production issues.

**Professional Skills:**

Programming Languages: JavaScript (ES6+), TypeScript

Frontend Development: React, Next.js, Vue.js, Nuxt.js, React Native, Vanilla JavaScript

Web Technologies: HTML5, CSS3, SASS/SCSS, LESS, Tailwind CSS, Bootstrap, Responsive Design, PWA

State Management: MobX, Redux Toolkit, React Query

Routing: React Router

UI Development: Data Grids, Formik, Yup, DnD Kit, Slate/Plate, Animations, Accessibility

Backend Development: Node.js, Express.js, Fastify

Databases: PostgreSQL, MongoDB, Redis

ORM/ODM: Prisma, Mongoose

API Development: RESTful APIs, Axios, Third-party API Integrations

Security: OAuth, JWT, RSA, RBAC, CORS, Two-Factor Authentication

Cloud Services: AWS, Firebase, Vercel, Supabase

DevOps & CI/CD: Docker, GitLab CI/CD, Jenkins

Build Tools: Vite, Webpack

Version Control: Git

Additional Skills: Frontend Architecture, Performance Optimization, Code Reviews, Mentoring, Product Development, Cross-functional Collaboration

**Languages**

- English — Upper Intermediate
- Ukrainian — Native