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Dmytro Kosianchuk

Frontend Engineer · Vue / TypeScript

Professional summary

Frontend Engineer with 5+ years shipping production web products in fintech and enterprise. Primary stack: Vue 3, Nuxt, and TypeScript — with a strong focus on SSR / hybrid rendering, predictable UX on critical flows, and performance as a product metric.

I build interfaces where money, documents, and compliance meet the browser: payment journeys, admin and internal tools, and document-heavy UIs. Comfortable working from product requirements through code review to release — with security-aware patterns and measurable Core Web Vitals improvements.

Core stack · SSR & product

  • Frameworks Vue 3 (Composition API), Nuxt 3 — SSR, SSG, hybrid routes, server/client boundaries, hydration
  • Languages TypeScript (strict, production-first), modern JavaScript (ES6+)
  • State & data Pinia, REST, WebSockets, integration with backend contracts
  • UI & quality HTML5, SCSS/CSS, responsive layouts, Figma-to-code, a11y awareness, unit & E2E testing
  • Delivery Git & code review, CI/CD, monitoring (e.g. Sentry), Agile / Scrum

Professional experience

Frontend Developer — Checkbox.ua

Fintech · March 2023 — February 2026
  • Delivered Nuxt-based product surfaces for fintech: SSR where it matters, fast client transitions elsewhere, predictable loading states on payment and admin flows.
  • Implemented complex, validation-heavy forms and transaction-related UI; defensive patterns around sensitive operations.
  • Built reusable components for checkout, dashboards, and internal tools; aligned with design system and code review culture.
  • Improved Core Web Vitals on conversion-critical pages (e.g. LCP improvements through profiling and refactors).
  • Contributed to document-management flows (e.g. Dubidoc — Checkbox product) as part of the frontend team: routing, UI states, drag-and-drop, PDF preview — within shared architecture.

Frontend Developer — EPAM Systems

Enterprise · 2021 — March 2023
  • Enterprise SPAs with Vue.js and React; dense business UIs with UX and accessibility requirements.
  • Strict TypeScript standards, shared patterns, documentation and knowledge sharing.

Layout Developer — Freelance

2019 — 2021
  • Semantic HTML/CSS, responsive layouts, JavaScript for UI behaviour and integrations; pixel-accurate delivery from design.

Education & courses

  • EPAM University — Frontend Development (Vue / React), 2021
  • EPAM University — Software Testing / QA Manual, 2021
  • Udemy — Advanced JavaScript & TypeScript, 2019

Languages

  • English — Intermediate (technical communication)
  • Ukrainian — Native

Strengths

  • Product mindset: UI defects and slowness treated as business risk
  • Ownership from spec to production; clear communication with backend & QA
  • Deep experience with payments, e-commerce, and regulated flows