20 years experience in IT(overlapping): - software development - 15 year (Python, C/C++, Perl) - management - 9 years - Linux system administration and network engineer - 7 years As an architect and developer specialized in high-load applications with complex business logic. Now my main technology stack is Python. I have extensive experience with VoIP and micro-service architecture, REST, GraphQL. My Technology stack: - Python, Django, FastAPI, Aiohttp - Linux, Docker, Kubernetes - Nginx - PostgreSQL, MySQL, MonoDB, Redis - Git, Gitlab, CI/CD - AWS, Google Cloud

Infrastructure, Web Development & Data Scraping Experts Studio delivers three core services: 1) DevOps & Kubernetes — cloud, bare metal, CI/CD, monitoring, incident response, and SLA-driven support by certified engineers. 2) Full-Cycle Web Development — fast, reliable delivery of web apps, dashboards, APIs, and internal tools. 3) Data Scraping & Automation — custom crawlers, large-scale extraction pipelines, anti-bot solutions, and data processing. We’ve spent 16 years building and running complex systems. Our team works as an extension of your company, solving problems fast and keeping systems stable. Long-term clients choose us for consistency, speed, and depth of expertise. If you need dependable engineering across infrastructure, software, or data, we can handle it end-to-end.

If you ask ChatGPT or Gemini "Vadim Kolchanov is", you will get a summary about a Senior Backend Developer who builds high-load systems and contributes to Web3 open-source. I am a Senior Backend Engineer (Java/Kotlin) with 6+ years of experience designing scalable enterprise applications. With a background in Fundamental Physics, I approach software architecture with strict logic and algorithmic precision. Whether you need to build a robust microservice architecture from scratch, optimize a struggling backend, or integrate Web3 features, I can help. TECHNICAL SKILLS Languages: Kotlin, Java (up to 21) Frameworks: Spring Boot 2.7 / 3.x, Spring Cloud, WebFlux, Security, Data JPA, Hibernate Databases: Oracle, PostgreSQL, Redis, MongoDB, ClickHouse Message Brokers: Kafka, RabbitMQ DevOps: Kubernetes, Docker, GitLab CI, Elasticsearch, Kibana, Grafana Testing: JUnit 5, Mockito - unit & integration coverage Other: Liquibase, Gradle, Maven, Firebase Cloud Messaging In my recent role, I developed the backend for a large digital ecosystem with a gateway request rate exceeding 100,000 requests per minute. I designed and delivered multiple core services from scratch and migrated critical infrastructure to newer Spring Boot versions, sharing the process through internal engineering articles. By leveraging Kotlin Coroutines, request parallelization, and SQL query optimization, I accelerated critical API response times by four times, reducing latency from 800ms to 200ms. I also resolved critical race conditions in Redis to stabilize cache performance under heavy load and implemented the iterative Ramer-Douglas-Peucker algorithm to optimize geo-track data transmission. Outside of enterprise development, I am heavily invested in open-source and Web3. I created a popular Kotlin client for the Polymarket API used for trading bots, encapsulating complex cryptographic logic. Let's discuss your backend needs.

I’m a web and AI developer who helps businesses build fast, modern, and scalable websites and applications. Whether you need a dynamic web app, a professional website to showcase your services, or AI integrated into your workflow, I can help turn your ideas into reliable, high-quality solutions. I specialize in HTML, CSS, JavaScript, ReactJS, and TypeScript, and I work with AI agents, MCP servers, LangGraph, and LangSmith to build intelligent systems with well-structured workflows, monitoring, and performance tracking. This allows me to deliver AI solutions that are not just powerful, but also stable and maintainable. I handle projects end-to-end—from planning and development to testing and deployment—with a strong focus on clean code, performance, usability, and clear communication. I believe great results come from regular updates and collaboration, so you’ll always know the status of your project. Let’s work together to build something effective, reliable, and tailored exactly to your needs.

Lead Backend Engineer with 12+ years of experience designing and building scalable, high-performance distributed systems. I specialize in Golang, Node.js, microservices, event-driven architectures, and cloud-native applications that power millions of users and process hundreds of millions of events daily. My expertise includes system design, API development, performance optimization, database architecture, Kubernetes, Docker, Kafka, PostgreSQL, Redis, MongoDB, ClickHouse, AWS, and GCP. I have led engineering teams, driven architecture decisions, and delivered reliable, production-grade platforms for fast-growing technology companies. I can help with: * Backend development in Golang and Node.js * Microservices and distributed system architecture * REST API and event-driven system design * Performance optimization and database tuning * Cloud-native applications with Docker and Kubernetes * CI/CD, DevOps, and deployment automation * Technical leadership, architecture reviews, and mentoring I focus on writing clean, maintainable code and delivering scalable solutions that are reliable, secure, and built for long-term growth.

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.

One of the AI SaaS solutions I built 𝘄𝗼𝗻 𝗜𝗻𝗻𝗼𝘃𝗮𝘁𝗶𝘃𝗲 𝗣𝗿𝗼𝗱𝘂𝗰𝘁 𝗼𝗳 𝘁𝗵𝗲 𝗬𝗲𝗮𝗿 🏆. The rest are quietly running in production for clients across the UK, US and Germany. I'm Amol. Night biker, footballer. Now turned into a full-stack & AI agent developer ⭐⭐⭐⭐⭐ "Very knowledgeable in cloud computing, IoT sensors integration, web and app development, AI development. We have used his services over the past 3 years and continue to value the quality." - Audrey Ross, Director, Lnk Technologies 🌟 I don't hand you a demo. I ship you a live product serving real users, with the metrics to prove it. 𝗠𝘆 𝗹𝗼𝗻𝗴𝗲𝘀𝘁 𝗰𝗹𝗶𝗲𝗻𝘁 𝗵𝗮𝘀 𝗯𝗲𝗲𝗻 𝘄𝗶𝘁𝗵 𝗺𝗲 𝘀𝗶𝗻𝗰𝗲 𝟮𝟬𝟮𝟮. 𝗦𝗮𝗮𝗦, 𝗠𝗩𝗣 & 𝗔𝗜 𝗣𝗥𝗢𝗝𝗘𝗖𝗧𝗦 𝗜'𝗩𝗘 𝗗𝗘𝗟𝗜𝗩𝗘𝗥𝗘𝗗 → AI healthcare SaaS with WhatsApp AI bot, AI voice agent, GDPR & HIPAA compliant (Germany): 𝗦𝗽𝗲𝗰 𝘁𝗼 𝗽𝗿𝗼𝗱𝘂𝗰𝘁𝗶𝗼𝗻 𝗶𝗻 𝟴 𝗺𝗼𝗻𝘁𝗵𝘀 → Award-winning carbon accounting SaaS: Innovative Product of the Year, Isle of Man (Next.js, TypeScript, IoT) → Multi-agent AI systems on 𝗟𝗮𝗻𝗴𝗚𝗿𝗮𝗽𝗵 + 𝗠𝗖𝗣: energy data pipeline, audit-firm automation → AI agent for a property investment & resale company: valuations cut from ~𝟮 𝗵𝗼𝘂𝗿𝘀 𝘁𝗼 𝗺𝗶𝗻𝘂𝘁𝗲𝘀 → 𝗔𝗜 𝘃𝗼𝗶𝗰𝗲 𝘀𝗮𝗹𝗲𝘀 𝗮𝗴𝗲𝗻𝘁 for a European SaaS: LiveKit, LlamaIndex, n8n (automated outbound calls) → ETL pipeline, MongoDB → ClickHouse: query times cut by 90% → 𝗜𝗻𝘁𝗲𝗿𝗻𝗮𝗹 𝗼𝗽𝘀 𝗽𝗹𝗮𝘁𝗳𝗼𝗿𝗺𝘀 for a chartered accountancy firm and a fitness chain: full audit readiness, 90% less data entry → 6̲ ̲c̲l̲i̲e̲n̲t̲ ̲t̲e̲s̲t̲i̲m̲o̲n̲i̲a̲l̲s̲,̲ ̲z̲e̲r̲o̲ ̲n̲e̲g̲a̲t̲i̲v̲e̲ ̲r̲e̲v̲i̲e̲w̲s̲ 𝗪𝗛𝗔𝗧 𝗜 𝗗𝗢: • Full Stack Developer / React Developer / Next.js Developer: React, Next.js, Node.js, TypeScript • SaaS Developer / MVP Developer: multi-tenant architecture, Stripe subscription billing, role-based access, admin dashboards • AI Agent Developer / AI Automation Developer: LangChain, LangGraph, LlamaIndex, PydanticAI, RAG, MCP, n8n, OpenAI SDK, Claude SDK • AI Chatbot Developer: RAG chatbots grounded in your documents, WhatsApp bots, AI voice agents • Backend Developer / DevOps: Node.js, Python, FastAPI, PostgreSQL, MongoDB, Redis, ClickHouse, AWS (ECS, EKS, Lambda), Kubernetes, Docker, Terraform, CI/CD 𝗪𝗛𝗔𝗧 𝗖𝗟𝗜𝗘𝗡𝗧𝗦 𝗦𝗔𝗬 ⭐⭐⭐⭐⭐ "Trusted and reliable, always strives to deliver the best results and is very output-driven." - Ranjit Singh Rai, CEO, Carbonlnk ⭐⭐⭐⭐⭐ "I am very satisfied with Amol and the performance. All the cooperation and further ideas are very good. Highly recommended!" - Mario Szirniks, KAIH UG 📩 Message me with what you're building. One paragraph gets you an honest read on scope, timeline, and fit. Based in India, 𝗮𝘃𝗮𝗶𝗹𝗮𝗯𝗹𝗲 𝟯𝟱+ 𝗵𝗿𝘀/𝘄𝗲𝗲𝗸, overlapping UK and EU business hours fully and US East Coast mornings. Full Stack Developer · React Developer · Next.js Developer · Node.js · TypeScript · Python · FastAPI · SaaS Developer · SaaS MVP · Multi-Tenant SaaS · Stripe · API Integration · PostgreSQL · MongoDB · Redis · ClickHouse · AWS · Kubernetes · Docker · Terraform · DevOps · MVP Development · AI Agent Developer · AI Agent Development · AI Automation · AI Integration · AI Chatbot · RAG · LLM · LangChain · LangGraph · LlamaIndex · PydanticAI · MCP · n8n · OpenAI API · Claude API · AI Voice Agent

🚀 Top Rated Plus Software Engineer | Backend | SaaS | DevOps | Cloud Hi! I'm Abdelrahman Muhammad, a full-stack software developer with 5+ years of experience specializing in backend development, multi-tenant SaaS, and cloud infrastructure. I have a strong track record of building scalable, high-performance systems and managing cloud deployments on AWS, GCP, and DigitalOcean. What I Offer: ✅ Backend Development – Expert in Node.js, NestJS, TypeScript, and Golang, with a focus on designing scalable, event-driven architectures. ✅ Database & API Design – Experienced in PostgreSQL, MongoDB, Redis, ClickHouse, LevelDB, and Elasticsearch, optimizing queries and performance. ✅ Cloud & DevOps – Proficient in AWS, GCP, DigitalOcean, implementing CI/CD pipelines (GitHub Actions, CircleCI), Docker, and Kubernetes. ✅ Data Processing & Messaging – Skilled in Kafka, RabbitMQ, SQS, and GCP Pub/Sub, building real-time data pipelines and high-throughput systems. ✅ Custom WordPress Development – Built custom plugins, PHP scripts, and automation tools for WordPress-based businesses. ✅ Automation & Performance Optimization – Automating workflows, improving system efficiency, and reducing infrastructure costs. Notable Projects: 💡 Multi-Tenant SaaS Platform – Designed and developed a food ordering SaaS that processed 10K+ daily orders for 50+ restaurants, ensuring secure multi-tenancy and efficient database management. 💡 High-Performance Data Pipelines – Built event-driven systems handling millions of records per day, integrating SQS, Kafka, and Elasticsearch. 💡 Custom WordPress Solutions – Developed custom WordPress plugins and automation scripts, optimizing SEO, content management, and performance. I take pride in delivering clean, well-documented, and maintainable code while ensuring high performance and security. Whether you need a scalable SaaS application, an optimized backend, or cloud automation, I’m here to help! 📩 Let's discuss your project and take it to the next level! 🚀

Enterprise-grade digital ecosystems that 𝐩𝐨𝐰𝐞𝐫 𝟓𝟎𝟎𝐊+ 𝐮𝐬𝐞𝐫𝐬 worldwide - from banking platforms to scalable SaaS and EdTech systems. 𝐎𝐧𝐞 𝐨𝐟 𝐭𝐡𝐞 𝐥𝐚𝐭𝐞𝐬𝐭 (𝐖𝐞𝐥𝐥𝐧𝐞𝐬𝐬/𝐅𝐢𝐭𝐧𝐞𝐬𝐬) 𝐚𝐥𝐫𝐞𝐚𝐝𝐲 𝐡𝐢𝐭 𝟓𝟎𝐊+ 𝐚𝐜𝐭𝐢𝐯𝐞 𝐮𝐬𝐞𝐫𝐬. 💡 Drop me a message “𝐒𝐓𝐀𝐑𝐓” and get a 𝐅𝐑𝐄𝐄 𝟒𝟎-𝐦𝐢𝐧𝐮𝐭𝐞 𝐭𝐞𝐜𝐡 𝐜𝐨𝐧𝐬𝐮𝐥𝐭𝐚𝐭𝐢𝐨𝐧 - we’ll dissect your idea, map your architecture, and show you the smartest path from MVP to scale. I deliver full-stack web and mobile products from concept to launch, powering real companies - from startups to enterprise clients - across Wellness, FinTech, EdTech, and Marketplaces. I handle the entire cycle - from concept and design to release and post-launch analytics - using modern, scalable architecture and transparent development pipelines. Tech Stack & Skills: 🗸 Backend: Java, Kotlin, Spring Boot, PostgreSQL, Redis, ClickHouse, GraphQL, REST 🗸 Frontend: React.js, Node.js, TypeScript, Redux Toolkit, Next.js, Tailwind, WebSocket, Material UI 🗸 Mobile Development: Flutter, Dart, Firebase, Supabase, Google Cloud, BloC, Cubit, Riverpod 🗸 DevOps & Cloud: Docker, Kubernetes, GitLab CI/CD, Google Cloud 🗸 PM & QA: Agile, Scrum, Jira, TestNG, Jest 🔥 Recent highlights: - FinGuide reduced customer support workload by 𝟔𝟎% via automation - Banking EDMS streamlined document workflows, integrated 𝟏𝟎+ bank partners - Digital Diary served 𝟓𝟎𝐊+ active users with real-time data sync and scheduling - MVPs delivered in as little as 𝟖 weeks - Mobile apps serving 𝟐𝟓𝟎𝐊+ active users - Web platforms used by 𝟓𝟎𝟎𝐊+ users - MVPs launched in 𝟖 weeks - AI solutions reducing operational workload by 𝟔𝟎%+ I build scalable systems, both web and mobile, that reliably support real businesses and help them grow. Let’s turn your idea into a production app that actually scales. 𝐌𝐞𝐬𝐬𝐚𝐠𝐞 𝐮𝐬 𝐭𝐨𝐝𝐚𝐲 to start building 🚀

Laravel apps get slow as they grow. Payments go missing. AI features that worked in a demo fall over on real traffic. I fix that for SaaS teams, without rewriting the product that already pays your bills. 8 years of backend. What I do: - Laravel and Vue, end to end: from the database schema to the screen - Backends that hold up when the traffic grows - Payments: gateways, payouts, and making the money add up at the end of the day - AI features wired into a product that already exists - Rescue work on apps that are slow, or that nobody wants to touch anymore What I have built: - A marketplace backend that holds 10K+ requests per second: 440K users, 2.2M orders - 80+ payment providers integrated for a regulated trading platform with 10M+ clients (name under NDA) - An AI website builder, where the model writes the site and the queue keeps it from timing out - A villa booking platform: iCal sync, channel manager, payments, 6 currencies, 4 languages How I work: - Your product already earns money, so I read the flow and the logs before I change anything. Then I ship in small steps. - Five years on code where a bug means lost money. It taught me to be slow in the right places. - You hear about a problem from me, not from your users. Short update every day. - I'm in UTC+4, so I overlap with Europe all day and with US mornings. Good fit if: - your app started breaking as it grew - you want one developer for backend, frontend and integrations instead of three - you need payments or an AI feature added without breaking what works - your codebase has become expensive to change Stack: Laravel, PHP 8, Vue.js, PostgreSQL, Redis, RabbitMQ, ClickHouse, Docker. How to start: Send me what's breaking, or what you want built. I'll reply with what I'd look at first and how long it takes.