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I’m a Senior Python Engineer and Full Stack Developer with 8+ years of experience building production-grade backend systems, automation platforms, scalable engineering infrastructure, web scraping infrastructure, automation platforms, betting software for startups, SaaS products, trading companies, and data-driven businesses. Clients usually contact me for projects related to Python development, Full Stack development, backend development, backend APIs, web scraping, data extraction, browser automation, Playwright automation, Selenium automation, Scrapy development, ETL pipelines, workflow automation, automation systems, API integrations, real-time data processing, AI automation, OpenAI integrations, scalable backend systems, sportsbook software, betting systems, odds aggregation, analytics platforms, SaaS products, and high-load real-time data systems. Why clients work with me ✔ 8+ years of Python engineering experience ✔ 6+ years of Full-Stack engineering experience ✔ $400K+ earned on Upwork ✔ 100% Job Success Score ✔ Top Rated Plus freelancer ✔ Production-grade scalable architectures ✔ Strong communication and reliable delivery ✔ Experience with high-load real-time systems ✔ Long-term technical partnership mindset As a Full Stack Developer and backend developer, I build backend systems, APIs, automation platforms, web applications, analytics dashboards, browser automation workflows, admin panels, and scalable real-time data products designed for production environments. Web Scraping & Automation As a Python developer specializing in web scraping and automation systems, I build scalable scraping infrastructure for dynamic websites, protected platforms, APIs, marketplaces, SaaS products, and analytics systems. Scraping and automation projects include: • Large-scale web scraping systems • Data extraction pipelines • Browser automation with Playwright and Selenium • Scrapy-based scraping infrastructure • API reverse engineering and API integrations • Proxy management and anti-bot workflows • Marketplace and e-commerce data collection Backend Development & Automation Systems As a Full Stack Developer and backend developer, I also build scalable backend systems, backend APIs, automation infrastructure, workflow automation platforms, web applications, and real-time backend services. Typical backend and automation projects include: • Backend API development • Workflow automation systems • Real-time automation platforms • Monitoring and reporting systems • Data synchronization systems • Web applications and admin dashboards • Cloud-based backend infrastructure Clients hire me as a Python developer and Full Stack Developer when they need scalable backend systems, automation workflows, real-time data processing, or production-grade infrastructure that can support long-term product growth. Sportsbook & Betting Systems I have strong hands-on experience building sportsbook software, betting systems, odds aggregation platforms, sportsbook data systems, and real-time betting infrastructure running in production environments. • Real-time sportsbook odds aggregation systems • Arbitrage and positive EV analytics platforms • Betting automation and execution systems • Historical odds databases and backtesting engines • Sports analytics dashboards and reporting systems • Odds monitoring and alerting systems AI Automation & Data Infrastructure • AI data collection pipelines • OpenAI API integrations • AI automation workflows • RAG and knowledge base infrastructure • AI enrichment and structured data processing My main stack includes: Python • FastAPI • Django • Flask • AsyncIO • REST APIs • GraphQL • Playwright • Selenium • Scrapy • WebSockets • Microservices • Celery • SQLAlchemy • Backend Architecture - Web Scraping & Data Engineering Playwright • Selenium • Scrapy • BeautifulSoup • Requests • Browser Automation • Data Extraction • Web Scraping • Data Mining • ETL Pipelines • Proxy Management • Pandas • NumPy • Dask • Scikit-learn • TensorFlow • PyTorch • XGBoost • OpenCV - Advanced Scraping Infrastructure Cloudflare • DataDome • Akamai Bot Manager • PerimeterX • reCAPTCHA • hCaptcha • Residential & Mobile Proxies • Session Management • Authentication Workflows • Browser Fingerprinting - Full Stack Development React • Next.js • TypeScript • JavaScript • HTML5 • CSS3 • Tailwind CSS • Admin Dashboards • SaaS Applications • Analytics Dashboards - Cloud, DevOps & Infrastructure Docker • Kubernetes • AWS • Google Cloud • Azure • GitHub Actions • GitLab CI/CD • Terraform • Ansible • Nginx • Linux AI & LLM Development OpenAI API • GPT-4 • Claude • Llama • AI Agents • RAG • Prompt Engineering • AI Automation • LLM Integrations • If you need a Python developer, Full Stack Developer, backend developer, or automation developer who can build scalable backend systems, automation infrastructure, web applications, sportsbook systems, or real-time data products, feel free to reach out.

I'm a backend developer working mainly with Node.js, NestJS and PostgreSQL. I build APIs, integrations and backend systems, and I’m also comfortable jumping into an existing codebase to fix problems or add new functionality. A lot of my work starts with an existing product rather than a blank repository. Sometimes a new feature needs to be added, sometimes an external service has to be integrated, and sometimes something simply doesn't work the way it should. I can help with: - REST APIs and backend development - NestJS / Node.js / TypeScript applications - PostgreSQL and database design - third-party API integrations - payment integrations - Redis, queues and background jobs - WebSockets and real-time functionality - Docker and deployment - debugging and performance issues - refactoring existing backend code My usual stack is NestJS, Node.js, TypeScript, PostgreSQL, Redis and Docker. Depending on the project, I also work with AWS, RabbitMQ/SQS, WebSockets, Prisma, TypeORM and Drizzle. I care about keeping code understandable and maintainable. I don't like introducing another service, abstraction or dependency unless it actually solves a problem. I'm also an experienced WordPress/PHP developer. WordPress is where a large part of my freelance career started, and you'll find many WordPress projects and client reviews in my Upwork history. I still work with WordPress when a project needs custom development, WooCommerce, plugin/theme work, API integrations or debugging that goes beyond installing and configuring plugins. My backend experience is particularly useful for WordPress projects involving external APIs, custom business logic or integrations. If you're starting something new, I can help you design and build the backend. If you already have a project, I'm equally comfortable opening the codebase, figuring out how it works and getting to work without trying to rewrite everything from scratch. Tell me a little about the project and what you're trying to solve. I'll be happy to take a look.

I’m a Java Backend Engineer with 5+ years of experience building backend applications, REST APIs, and microservices. I work with Java and the Spring ecosystem to build reliable, maintainable backend systems. I can help with new development, improving existing codebases, fixing bugs, integrating services, and making backend applications easier to support and scale. What I can help with: • Backend development with Java and Spring Boot • REST API development and integration • Microservices design and implementation • Database design and optimization • Kafka and RabbitMQ integration • Refactoring legacy code • Performance improvements and bug fixing • Writing tests and improving code quality Tech stack: • Java 8+ • Spring Boot, Spring MVC, Spring Data, Spring Security • Hibernate / JPA • PostgreSQL, MySQL, Redis • Kafka, RabbitMQ • Docker • Maven, Gradle • Git, GitLab CI/CD • JUnit, Mockito I also use modern AI-assisted development tools when they help speed up research, routine implementation, debugging, or documentation. At the same time, I always keep the focus on code quality, maintainability, and practical engineering decisions. I care about writing clean code and building backend solutions that are stable, scalable, and easy to maintain. If you’re looking for help with a Java backend project, microservices, or API integrations, feel free to reach out.

🚀 Full Stack Developer | Web & Mobile Specialist I have 7 years of hands-on experience building dynamic, responsive, and user-centric applications. I am an experienced Fullstack developer who brings designs to life with clean, user-friendly, and highly performant code. I combine stunning UI/UX with powerful backend logic. My strength lies in transforming complex requirements into elegant, scalable applications that are intuitive, fast, and reliable. 💡 Expertise in technical stacks 📍Frontend: React, React Native, Next.js JavaScript, TypeScript HTML, CSS, Tailwind CSS, SASS Material UI, Bootstrap Responsive and accessible design 📍Backend: Node.js, Express.js, NestJS RESTful API, GraphQL Authentication and authorization 📍State management and tools: Redux, Redux Toolkit Git and GitHub for version control 📍Databases: MongoDB, MySQL, PostgreSQL ✨ Whether you’re launching a startup, scaling an existing product, or simply looking to revamp your digital presence, I’m here to bring your vision to life with cutting-edge solutions and reliable execution. 📩 Let’s build something great together. Reach out today, and let’s turn ideas into amazing digital experiences.

Thank you for viewing my profile! I have been working as a freelancer/remote developer for more than 10 years solo as well as in a team. I have experience in full stack development from scratch to release, including backend and iOS/Android applications. and Web3 projects. My latest Golang/Crypto works include EVM/Solana trading bot and Solana token prices indexer. My latest python/crypto works include arbitrage app for bsc, frontrunning & backrunning bots, txs repeater bot, blockchain scanner-analytical bot and rest apis for the mobile apps. My latest mobile works include social media analytics app, bitcoins exchange app, customizable weather app, fax app, encrypted photo album app, document editor app, whatsapp companion app for Apple Watch, QR code scanner/generator app. Skills: Golang development: Golang, MongoDB, ClickHouse, Rust, TXs decoding, REST API, Websockets, EVM & Solana nodes maintenance, Telegram API Python development: Python, GETH for ETH & BSC nodes, Web3, networking, sqlite, PostgreSQL, Rest api, firebase, telegram api, bloxroute, frontrunning txs, custom routers, arbitrage swaps etc. Android development: Android SDK, Kotlin, RxKotlin, Synthetic, Kotlin Android Extensions, Dagger 2, Git, RxJava, Java, AndroidX, RxDatabinding, Navigation Components, Realm, Room, SQLite, NoSQL, SQL, OpenGL, Retrofit, REST json, Butterknife, Picasso&Glide, Firebase SDK (cloud functions, cloud messaging, storage, push notifications, social auth), Google console, Google Maps API, Yandex Kassa API&SDK, Dropbox SDK, java sockets, Crashlytics, Widgets, Generating&Scanning QR codes, VK SDK, FB SDK, Android keystore, Android fingerprint, OpenCSV, apk uploading to play market, familiarization with software development methodology, good knowledge design patterns, MVVM/MVP/MVC, clear code, Scrum, Kanban methodology, asana, trello task tracker, interesting in blockchain projects. IOS development: IOS SDK, WatchOS SDK, WatchKit, WatchConnectivity, Swift, RxSwift, Alamofire, CoreData, RealmSwift, Realm, RxRealm, Kingfisher, Swinject, UIKit, WebKit, MVP/MVVM/MVC, Firebase SDK, CoreLocation, Cocoapods, Git, SourceTree, XCode.

🥇 Top Rated Freelancer on Upwork 🥇 5 plus Years of Experience in Manual QA 🥇 Full coverage Manual QA for Web and Mobile products, including API validation 🥇 Clear, developer friendly test documentation and bug reports 🥇 Smooth cooperation in remote teams and Agile workflows Performing such types of testing ✅ Manual ✅ Exploratory ✅ Functional ✅ System ✅ Regression ✅ Smoke ✅ UI and UX testing ✅ Cross browser and compatibility testing ✅ API testing Also have hands-on experience with Test Automation 🤖 Automation QA (AI-assisted): built and maintained automated test scripts leveraging AI tools (Claude, ChatGPT) to accelerate script writing, debugging, and maintenance, combining manual QA expertise with modern AI-powered automation workflows Experienced in Reviewing requirements and clarifying acceptance criteria before testing starts Creating practical test scenarios and test cases based on real user behavior Reporting bugs with clear reproduction steps, expected versus actual results, and evidence Supporting fast release cycles by verifying fixes and running regression before production Working closely with developers and product leads to reduce regressions in complex workflows Technical expertise in Manual QA includes 🔎 Management tools: Jira, Azure DevOps, TestRail, Trello, Confluence, Asana 🔎 API testing: Postman, Swagger 🔎 Debugging: Datadog, Splunk, Amplitude 🔎 Cross browser testing: BrowserStack, LambdaTest 🔎 Databases: basic SQL, PostgreSQL 🔎 Remote collaboration: clear async updates and structured status reporting 🔎Mobile testing: TestFlight, Google play, Firebase, Appstore connect I have worked with SaaS style products and workflows where many objects and calculations depend on each other, so I test not only isolated features but also system behavior and edge cases. I will be glad to help your team ship stable releases that meet business needs and feel reliable for users. Feel free to message me and share your product scope. QA Tester, Manual QA, Software Quality Assurance, Web and Mobile Testing, SaaS QA, Functional Testing, Exploratory Testing, Regression Testing, Smoke and Sanity Testing, End to End User Flows, UI and UX Testing, Responsive Design Testing, Cross Browser Compatibility, iOS and Android App Testing, UAT Support, Release Verification, Production Checks, Bug Reporting, Defect Triage, Repro Steps, Test Cases and Checklists, Test Plan, Acceptance Criteria Review, Requirements Validation, Edge Case Coverage, API Testing, REST API Validation, Postman, Swagger, Chrome DevTools, Network Logs, HAR Capture, SQL Queries, PostgreSQL, Salesforce QA, SOQL, Stripe Payments Testing, Webhook Validation, Analytics Tracking Validation, Amplitude, Jira, TestRail, Confluence, Azure DevOps, Trello, BrowserStack, LambdaTest, TestFlight, Firebase, App Store Connect, Remote Testing, Azure Virtual Machines, AnyDesk, Localization QA, Content QA, Data Integrity Checks, Calculation Validation, Session Based Testing, Agile QA, Sprint Testing, Automation QA, Test Automation, AI Assisted Test Automation, Automated Test Scripts, Script Maintenance, Low Code Automation, AI Powered QA Workflows