Olha S.
Senior Full-Stack Engineer React Next.js Shopify AI SaaS Typescript
Hey! You're here to find a Full-Stack Developer who delivers real results. I specialize in building scalable, high-performance web applications - SaaS platforms, Shopify storefronts, AI-powered apps, dashboards, and marketplaces. 5 years of experience, 20+ production projects shipped. Whether it's a greenfield build or an existing product to improve - I handle everything from frontend UX to backend architecture and deployment. I don't just write code - I take ownership of the result. Not every project needs full end-to-end ownership - I also take on frontend-only engagements when a team just needs strong React/Next.js execution without touching the backend. I use AI tools daily to deliver faster without sacrificing quality. Claude Code and Cursor are my core development environment - I write, review, and refactor code with them every day. For UI prototyping I use v0 and Bolt to go from idea to working interface in hours, not days. ChatGPT, Gemini, and Perplexity for research, debugging, and quickly exploring unfamiliar domains. GitHub Copilot for in-editor completions. Lovable and Replit Agent for rapid scaffolding when speed matters. This isn't a trend I follow - AI tooling has been part of how I work for the past year, and it shows in delivery speed. My backend work leans on secure API design, careful data handling, and proper auth (JWT, OAuth) - a foundation that fits compliance-sensitive domains like healthcare and fintech just as well as it fits a standard SaaS build. ✨ What I bring to the table 5 years of full-stack experience in real production projects 20+ shipped products - SaaS MVPs, marketplaces, Shopify apps, AI platforms Fluent English - clear, fast, and transparent communication Ownership mindset - I don't just code, I take responsibility for the result Reliable delivery - clean code, on time, no surprises Strong focus on performance, scalability, and user experience Experience working independently and in cross-functional teams (Scrum, Agile) 🛍️ Shopify Development Custom Shopify storefronts and theme development Shopify Storefront API and Admin API integrations Shopify app development (public and private apps) Hydrogen / Oxygen - headless Shopify with React Shopify Checkout customization and Checkout Extensions Third-party integrations: payments, inventory, CRM, logistics Migrations to Shopify from custom platforms 🎟️ Marketplaces & Booking Platforms Two-sided and multi-vendor marketplaces, booking/reservation flows, and ticketing systems - search and filtering, availability logic, and payment orchestration for platforms that connect buyers and sellers, or hosts and guests. 🛠️ Tech Stack Frontend React Next.js (SSR App Router) TypeScript Redux Zustand TanStack Query Tailwind CSS Material UI Shadcn UI Framer Motion styled-components React Hook Form Zod Yup Chart.js Recharts ApexCharts Backend Node.js Express.js NestJS REST APIs GraphQL WebSockets Socket io JWT Auth0 OAuth Databases & Storage PostgreSQL MongoDB Firebase Supabase Neo4j Pinecone Redis Integrations Stripe Twilio SendGrid OpenAI API Algolia ElasticSearch DevOps & Cloud Docker CI/CD GitHub Actions GitLab AWS (EC2 Lambda S3 RDS Cognito API Gateway) Vercel Netlify Testing & Quality Jest Mocha Supertest Postman ⭐️ Why clients choose me I solve business problems, not just technical tasks I think beyond code - suggesting better architecture, UX improvements, and scalable solutions before they become expensive problems. Fast and efficient development With 5 years of production experience and daily AI tooling, I deliver quickly without cutting corners - critical for MVPs and fast-moving products. Full-cycle development From idea - architecture - development - deployment - scaling. You don't need 3 different developers - I cover the whole process. Clean, maintainable code Well-structured, documented, and easy to scale - your next engineer will thank you, not curse you. Focus on results My goal isn't to close tickets. It's to help your product grow. Easy to work with Responsive, proactive, always aligned with your goals. I flag problems early and communicate before they become blockers. Have an idea, MVP, or existing product to improve? Let's talk - I'll help you define the right technical approach and deliver something that actually works 🚀
Earnings and projects
Last 6 months ÷ 6
Last 6 months: $10k
Billed in all: $35,955$36k
$2.1k in the last 6 months
Earnings, last 30 days
Skill rankings: Top 7% in Tailwind CSS
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