Nikolay S.Private profile: Upwork shows its earnings only to signed-in members, so we check it every few weeks, not daily. MRR here is a rough estimate (Upwork's six-month earnings ÷ months active). Last read Nov 5, 2026.

E-commerce | AI-Driven Platforms | Web3 | SaaS Architect | Shopify | WordPress | CMS I’m a Principal Engineer who has led and delivered projects across the full spectrum from early business requirement gathering and architecture design to frontend/back-end development, deployment, and long-term maintenance. Over the past 10+ years, I’ve built complex E-commerce systems, AI-powered platforms, and Web3 applications, always owning the full SDLC (Software Development Life Cycle). My focus is turning business ideas into scalable, maintainable, and high-performing digital products that directly drive growth and customer success. ⚙️ Core Technical Expertise Frontend / Web - React.js, Next.js (SSR/SSG/ISR), Redux, Zustand, Recoil - TypeScript, JavaScript (ES6+), TailwindCSS, SCSS, Material UI, Ant Design - Vue.js, Nuxt.js, SvelteKit, Astro - Pixel-perfect UI implementation from Figma or Adobe XD - Progressive Web Apps (PWA), Responsive design, Accessibility (WCAG) Mobile - React Native, Expo, Flutter, Swift (iOS), Kotlin (Android) - Shared UI libraries, API integration, Firebase push notifications Backend - Node.js (Express, NestJS, Fastify), Python (FastAPI, Flask, Django), PHP (Laravel, WordPress, WooCommerce) - Golang, Rust (for performance-critical services) - REST & GraphQL APIs, WebSockets, gRPC, Apollo Server - Authentication systems (JWT, OAuth2, Supabase Auth, Firebase Auth, Clerk, Auth0) Databases & Storage - PostgreSQL, MySQL, MongoDB, Redis, DynamoDB, Elasticsearch, Firestore - Prisma, TypeORM, Sequelize, Mongoose - Data warehousing: BigQuery, Snowflake, ClickHouse - File storage: S3, Cloudinary, Supabase Storage DevOps / Cloud / CI-CD - AWS (EC2, Lambda, ECS, S3, RDS, CloudFront) - GCP (Cloud Run, Firestore, Cloud Scheduler), Vercel, Netlify - Docker, Kubernetes, ArgoCD, GitHub Actions, Jenkins, CircleCI - Nginx, PM2, Terraform, Pulumi - Monitoring: Grafana, Prometheus, Datadog Architecture & Systems - Monolithic & Microservice Architectures - Event-driven systems (Kafka, RabbitMQ, SQS, Pub/Sub) - Serverless functions (AWS Lambda, Cloud Functions) - Scalable caching (Redis, CDN-level, local memory) - CQRS, DDD, Clean Architecture principles E-commerce & SaaS Platforms - Shopify (custom apps, Storefront API, Hydrogen) - WooCommerce, Magento, BigCommerce, Strapi - Custom E-commerce platforms with Next.js + Node/PostgreSQL - Stripe, Paddle, PayPal, Braintree integrations - Multi-tenant SaaS systems with subscription management - Admin dashboards, analytics, and marketing automation tools AI & Data Integration - OpenAI API, LangChain, RAG chatbots, embeddings search - TensorFlow, PyTorch, ONNXRuntime for model inference - Recommendation systems, personalization pipelines - Data pipelines (dbt, Airflow, Prefect), feature stores (Feast) Web3 / Blockchain - Solidity, ethers.js, web3.js - Smart contract deployment (Ethereum, Polygon, BSC) - Wallet integrations (MetaMask, WalletConnect) - NFT minting, marketplace, token-gated content 🚀 What I Deliver - Pixel-perfect E-commerce stores (Shopify, Next.js custom, WooCommerce) - Scalable SaaS platforms with subscription billing and admin dashboards - Microservices & API architectures ready for millions of requests - Serverless systems that scale automatically - AI-integrated solutions; chatbots, content generation, recommendation engines - Web3 applications; wallet login, NFT minting, on-chain analytics - Mobile apps; React Native & Flutter with synchronized back-end 🧭 Work Philosophy - I treat every project as if it were my own product. - Fast iteration with clean, maintainable code. - Business-oriented thinking: always focused on ROI and scalability. - Proactive communication, transparent progress updates, and clear documentation. - Guaranteed delivery; I consistently ship high-quality results ahead of schedule. 🌟 Why Clients Hire Me ✅ Principal-level engineer who owns full SDLC from vision to production. ✅ Consistently deliver fast, reliable, and scalable results. ✅ Long-term focus: I design systems that are future-proof and ready for growth. ✅ Strong product mindset; I align technical solutions with business goals. If you’re looking for a senior full-stack engineer who leads architecture, execution, and delivery across E-commerce, AI, or Web3, let’s talk. I’ll help you turn complex ideas into beautifully built, revenue-driving software.