Руслан

RUSLAN RASTEHAIEV
9 years experience

Frontend Engineer | React.js | Next.js | TypeScript

Email: [open contact info](look above in the "contact info" section)
LinkedIn: [open contact info](look above in the "contact info" section)
GitHub: https://github.com/markupchef
Location: Germany, Cologne

Professional Summary
Senior Frontend Engineer with 9+ years of experience building scalable web applications
and 5+ years specializing in React.js, Next.js, and TypeScript. Skilled in designing clean
architectures, optimizing performance, and ensuring accessibility (WCAG 2.1 AA).
Experienced across startups, outsourcing, and enterprise environments with proven
leadership as a mentor and Head of Development.

Key Skills
Core: React.js, Next.js (SSR SSG, ISR), TypeScript, JavaScript (ES6+), REST API, HTML5,
CSS3/SCSS, Accessibility (WCAG AA), Web Performance Optimization, PWA (PWA
Studio), GraphQL (Apollo Client)
Secondary: Redux Toolkit, RTK Query, WebSockets, Tailwind CSS, Material UI (MUI), Ant
Design,Testing (Jest), CI/CD (GitHub Actions), Stripe (Payments Integration), MongoDB, AI
(OpenAI API)
Tools: Git, Docker, Copilot, Cursor (Coding boosting), Figma, Agile / Scrum workflows
Soft: Responsible and tactful, Problem-solving, Result and details oriented, Communication,
Teamwork skills, Great initiative, High social adaptability

Professional Experience

Senior Frontend Engineer (React.js) — Decima Digital Inc.
04.2024 – 06.2025 | Remote | Full-time

●​ Developed and launched a global e-commerce PWA platform for a pharmaceutical
company with operations in 59 cities.
●​ Optimized performance and configured Content Security Policy (CSP), ensuring
stable, secure, and fast user experience.
●​ Ensured WCAG 2.1 AA accessibility compliance, making the platform inclusive for a
worldwide customer base.
 ●​ Collaborated with cross-functional teams (security, SEO) to align product delivery
with business and compliance goals.
●​ Delivered the first project phase to production on schedule, meeting all performance
and accessibility requirements.
Tech Stack: PWA Studio, React.js, GraphQL (Apollo Client), Tailwind CSS, Informed.js, Jest

Senior Frontend Engineer (React.js / TypeScript) —
YozmaTech-Empowering Tech Entrepreneurs
07.2023 – 04.2024 | Remote | Full-time

●​ Led the frontend architecture and development from scratch for a SaaS platform
enabling restaurants to manage staff, menus, inventory, and real-time orders.
●​ Built MVP within strict deadlines, mentoring a junior developer and ensuring code
quality through reviews and knowledge-sharing sessions.
●​ Implemented real-time order tracking via WebSockets (pusher.js, laravel-echo),
enabling instant updates across restaurant dashboards.
●​ Designed and delivered multi-tenant subdomain architecture, allowing each
restaurant to operate under its unique domain within a single app.
●​ Developed secure role and plan-based access control, scaling the product for
different subscription tiers (staff limits, inventory features, etc.).

Tech Stack: React.js, TypeScript, Redux Toolkit, RTK Query, Ant Design, Tailwind CSS

Senior Frontend Engineer ( Next.js / TypeScript) — Project Job
02.2023 – 04.2024

●​ Created and launched MVP of an AI-powered platform helping IT professionals
prepare for interviews through test-style questions generated dynamically based on
role and seniority level.
●​ Owned end-to-end delivery: architecture, frontend and backend implementation,
CI/CD setup, Stripe payments integration, and database design.
●​ Collaborated with a UI/UX designer, transforming business requirements into a
working B2C product.
●​ Leveraged Next.js, TypeScript, RTK Query, MongoDB, and OpenAI API to build a
scalable and fast prototype.
●​ Implemented secure payment flow (Stripe API + MongoDB tracking) and real-time
access validation for paid sessions.
●​ Gained hands-on experience with server setup and CI/CD pipelines (GitHub Actions
+ Next.js deployment).
●​ Achieved 100+ user registrations in free mode within the first release phase.

Teach Stack: Next.js, TypeScript, Redux Toolkit, RTK Query, Ant Design, Tailwind CSS,
MongoDB (Mongoose), CI/CD
Middle Frontend Engineer (Next.js / TypeScript) — Altamira
05.2022 – 01.2023 | Remote | Full-time

●​ Contributed to the migration of a high-traffic sports events platform (200k+ concurrent
users) to a modern stack (Next.js).
●​ Delivered performance-optimized search experience using memoization, lazy
loading, virtual lists, and pagination to ensure stability under heavy loads.
●​ Recreated the SEO-critical URL and content structure by auditing the legacy site
(Screaming Frog) and implementing a matching routing system in Next.js.
●​ Collaborated closely with backend and SEO teams to balance scalability, user
experience, and search ranking preservation.

Tech Stack: Next.js, TypeScript, Material-UI, REST API, React Hook Form, Yup

Five4dog
04.2020 – 05.2022 | Hybrid | Full-time

Head Of Development Department
10.2021 – 05.2022 | Hybrid | Full-time

●​ Led and mentored a team of engineers: conducted interviews, distributed tasks,
managed workloads.
●​ Oversaw project evaluation and architecture decisions for client solutions.
●​ Introduced best practices in frontend workflows (reusable patterns, optimization,
code reviews).
●​ Balanced leadership with hands-on coding, ensuring delivery quality under deadlines.

Tech stack (hands-on work): React.js, Redux Toolkit, Tailwind CSS, SCSS, BEM, Git

Frontend Engineer
04.2020 – 10.2021 | Hybrid | Full-time

●​ Worked as the core Frontend engineer in a web studio, responsible for delivering
client projects end-to-end.
●​ Built responsive, cross-browser layouts and reusable UI components using HTML5,
SCSS, JS (ES6), BEM, Bootstrap.
●​ Developed dynamic functionality for WordPress and OpenCart projects.
●​ Delivered first SPA prototypes using React.js,, Redux Toolkit, Axios, React Hook
Form, Tailwind CSS.
●​ Focused on performance optimization (Lighthouse audits, lazy loading, asset
bundling) and analytics (Google GTM event tracking).

Tech stack: React.js, Redux Toolkit, Tailwind CSS, HTML5, SCSS, BEM, Git
Full-stack Web Developer — Safari Concern
06.2015 – 07.2019 | Remote | Part-time

●​ Developed and maintained multiple websites for fitness clubs across different cities,
covering both frontend (HTML5, CSS3/SCSS, JavaScript, Bootstrap) and backend
(PHP, MySQL) parts.
●​ Built custom admin panels and user dashboards to support business operations.
●​ Integrated CRM systems and online payment solutions.
●​ Collaborated closely with the marketing team to quickly launch and optimize landing
pages for business campaigns.

Tech stack: HTML5, CSS, SCSS, Bootstrap, JavaScript, Git, Page Speed Optimization

This role gave me a broad technical foundation, after which I transitioned to focusing fully on
modern frontend development (React.js, TypeScript).

Junior Web Developer — Freelance
03.2013 – 05.2015 | Remote | Part-time

●​ Created websites and landing pages for small businesses (beauty salons, travel
agencies, service providers), implementing HTML5, CSS3, JS, jQuery.
●​ Designed layouts and basic functionality for client projects, adapting solutions to
business needs.
●​ Self-initiated learning of web technologies, building own small projects to explore
frontend development.

Tech stack: HTML5, CSS, Bootstrap, JavaScript

Education
Higher education, Bachelor, 2011 – 2015

Languages
English (B2), Ukrainian (native)

Interests
Gym, Healthy food, Electronic music festivals