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Seeking opportunities in Java/Perl/Python oriented development, shell scripting, BSD/Linux administration - to support your business. Java: Spring, Hibernate Perl: Catalyst/Mojo/Dancer, DBIx::Class Python: Django, FastAPI, SQLAlchemy DB: Postgres, MySQL/MariaDB On-hand experience with regular expressions (regexp), REST, and AJAX. I can work well alone and as a team member.

I build production-grade SaaS platforms — multi-tenant architecture, clean component systems, and backends that scale. Over the past several years I've led engineering on 50+ delivered projects across healthcare, fintech, EdTech, logistics, and proptech — from greenfield MVPs to taking over and stabilizing existing codebases. Recent work includes: A multi-tenant SaaS platform with hard tenant isolation enforced at the DB/API layer, role-based access, and usage-based billing A route-management SaaS built from scratch — web dashboard + mobile apps — delivered in 3.5 months A vacation-rental platform backend rebuild that scaled connected properties 80x in 3 months A telehealth consultation platform delivered in 6 weeks under a hard deadline Team-augmentation engagements embedding senior React engineers directly into client teams for long-term product development Core stack: React.js, Next.js, TypeScript, Node.js, PostgreSQL, AWS — with real experience in Stripe billing, REST/GraphQL APIs, and CI/CD pipelines. I focus on performance, maintainable architecture, and shipping fast without cutting corners on scalability. Comfortable owning a feature end-to-end or leading a small team through a multi-phase build. Open to both project-based work and ongoing collaboration.

I’m a Senior Web Developer, Team Lead, and Software Architect with over 20 years of experience building robust web applications across a wide range of industries and domains. Soft Skills • Leading and organizing agile development processes • Translating ideas into clear wireframes and product concepts • Designing scalable and efficient database architectures • Building and mentoring high-performing teams • Communicating effectively with non-technical stakeholders Technologies • Ruby on Rails • PostgreSQL, MySQL, Neo4j, Elasticsearch • JavaScript (Stimulus, Turbo.js, Vue.js) • Linux system administration, AWS, Heroku, Docker • HTML5, CSS, Tailwind If you have an idea for a project or need technical leadership, feel free to get in touch.

😊 11+ years of commercial experience as Software Engineer 💻 I have a reliable team that is helping me to fill any role that is needed on a project. Any level of expertise, any budget, under my supervision I'm an experienced ASP.NET Developer with 11+ years of hands-on work: 6 production platforms, 120,000+ end users, 27 Upwork contracts and 5 active long-term clients (the longest for 4 years). I build and maintain web applications on ASP.NET Core, ASP.NET MVC and C# .NET: taking over existing codebases (9 so far, the oldest from 2008), fixing production issues and shipping features on time. 98% of my milestones landed on or before the agreed date, and 12 of my 13 Upwork reviews are 5 stars. As an ASP.NET Developer and Team Lead I've led teams of 5 to 13 people in business management, trading, healthcare, HR and logistics. I improved an existing ASP.NET MVC application by 30-80% (heaviest report page from 3.4s to 0.7s, API p95 from 900ms to 180ms, SQL Server CPU down 45%) through tuning, indexing and caching. I've found the root cause of 60+ production issues nobody could reproduce, 3 of them open over a year. I own architecture decisions, not just implement a spec: 3+ years of event-driven microservices on MassTransit and RabbitMQ (14 services, 1.2M+ messages a day, 99.95% uptime), 6+ years of monolithic ASP.NET Core solutions, and one enterprise system built from scratch in 12 months, on time and 8% under budget, as the lead .NET Developer of a 12-person team. I've been a backend developer on C# .NET (C sharp) 11+ years: ASP.NET Core, ASP.NET MVC, ASP.NET Web API, .NET Framework, .NET Core and Entity Framework, 250+ REST API endpoints shipped, 35+ third-party API integrations (payment, carrier, CRM), SignalR real-time features for 8,000+ concurrent users, and databases up to 600 GB and 900M rows on SQL Server, PostgreSQL, MySQL, CosmosDB, Redis and MongoDB, 1,200+ stored procedures written, 40+ slow queries brought under 1s. I've worked as an ASP.NET Web Developer on the full stack for 3+ years with Angular, React, jQuery, TypeScript, JavaScript, HTML5 and CSS: 4 SPAs delivered, 300+ UI components, Lighthouse above 90. I'm a full stack developer who owns both the C# backend and the UI. Cloud and DevOps: 3 years on Azure, plus AWS, GCP, Docker, Kubernetes and Azure DevOps CI/CD pipelines: 20+ built, 2-week releases turned into daily deploys, release time from 4 hours to 25 minutes, Azure spend cut 30% on one platform. I run ASP.NET Core workloads on Azure; for data pipelines I bring in the Azure data engineer on my team. Security and quality: OAuth 2.0, JWT, Fortify, 5 pen-test cycles, every critical finding closed within 1 sprint, load testing to 5,000 concurrent users, 80%+ unit-test coverage on my last 3 projects, DataDog monitoring with 25+ dashboards. I communicate clearly and proactively in fluent English with technical and non-technical people, overlap 6+ hours with US and EU time, and reply within 1 business hour. PROJECTS I've delivered as ASP.NET Developer 1. Business Management Platform. ASP.NET MVC and ASP.NET Core for 1,200+ businesses and franchise sites. Real-time messaging with SignalR to 8,000+ concurrent employees, 50,000+ messages a day on SQL Server, CosmosDB and Azure. 2. Commodity Trading Portal. Technical Lead on ASP.NET Core and Angular with a 9-person team for 18 months. Designed the architecture, reviewed 600+ pull requests, MassTransit across 4 databases, 0 lost transactions. 3. Healthcare Portal. Team Lead for an 11-person team. Existing app performance up 30-80%, slowest queries from 18s to under 1s, 120+ bugs closed in the first 3 months, release time from 4 hours to 25 minutes. 4. Enterprise Feedback System. .NET Core microservices built from scratch in 12 months, on time, for 25,000+ employees across 40 countries, 6 services, 2M+ feedback records. 5. Warehouse Logistics. Team Lead on ASP.NET MVC, ASP.NET Web API and React for 3 years. 3 distribution centres, 400+ trucks tracked daily, 99.9% uptime, 2 on-site visits to Canada. 6. Social Network for Car Drivers. ASP.NET MVC for 45,000+ registered drivers, 300,000+ posts and 1M+ real-time notifications a month with SignalR. ALSO EXPERIENCED AS C# Developer and C# .NET Developer on desktop and services: WPF, .NET MAUI and Blazor, 3 shipped apps; my core is ASP.NET Core on the web. I've done web developer work on PHP and Laravel integrations myself, and for anything outside my stack I bring in the right person from my team, under my supervision: a Java developer and a Python developer for shared APIs, a UI/UX designer (I build the designs pixel-accurate), a Flutter and Ionic developer for mobile apps. I take the ASP.NET Developer role myself. Certified: MCSD, Exam 486 (ASP.NET MVC), Azure Fundamentals. If you need an ASP.NET Developer who owns the whole delivery, architecture, C# .NET backend, Angular or React frontend, SQL Server and Azure, send me the scope and you'll have a plan and estimate within 24 hours

Full stack developer walks into a bar. The bartender asks, "What'll it be?" They say, "I'll take one of everything — and I'll build the menu while I wait." 🍺 🚀 5+ years of experience as a full stack developer React Node specialist, delivering 50+ robust and secure web applications for scaling a startup, shipping an MVP, or building a production-ready SaaS platform from early-stage concept through enterprise deployment. ✅Over 5 years building real-world web applications ✅Proven track record with 100% Job Success Score ✅Consistently earning 5⚝ client feedback ✅100% clean, scalable, production-ready code As a full stack developer and backend developer, I bring 10,000+ hours of proficiency in JavaScript, React TypeScript, and backend Node.js architecture. My passion for clean code and strong problem-solving skills help my team deliver 200,000+ hours on Upwork. I'm proactive, communicative, and able to take ownership of features independently, ready to become an ideal strategic partner for clients seeking a 100% full-time engineering role. 🏅As a full stack developer React Node, I implemented over 50 successful cutting-edge solutions using JavaScript (ES6+) with React TypeScript, and earned about $30K+ on Upwork. 🏅As a front end developer React with 10,000+ hours of strong experience, I built 50+ modern interfaces using React TypeScript, Next.js, Tailwind CSS, Material UI, Angular, Vue.js, and Redux Toolkit. 🏅ReactJS TypeScript and React Native TypeScript extend my delivery across web and mobile app developer contexts for over 3 years. 🏅I delivered 100% responsive design, Lottie animations, PWA implementations, and performance optimization for 30+ apps. 🏅As a React developer, I write clean code standards with 90%+ test coverage using Jest and Cypress QA frameworks. 🏅As a backend developer, I architect scalable backend Node.js services using Node.js, NestJS, and Express.js for my 3 Upwork projects. 🏅As a Python full stack developer, I bring additional backend Node.js versatility across data processing pipelines for about 1000 hours on Upwork. 🏅I handled API development, REST API and GraphQL integrations, role-based access control, CI/CD pipelines, and implemented secure authentication patterns for 20+ projects. 🏅As a full stack developer React Node, for over 5 years I manage environment across AWS and Google Cloud Platform (GCP) with Docker containerization. 🏅As a MERN stack specialist, for 50+ solutions I delivered comprehensive full stack developer React Firebase, full stack developer Supabase React, and full stack web developer solutions across PostgreSQL, MongoDB, and MySQL databases. 🏅My 3+ years of proven experience as a full stack developer AI includes OpenAI API integration for intelligent feature development. PORTFOLIO HIGHLIGHTS 🏆As a full stack developer AI and full stack developer React, I built an AI-powered SaaS growth suite for eCommerce marketplace sellers, integrating OpenAI API for customer segmentation and analytics dashboard. Stack included React TypeScript, NestJS, PostgreSQL, AWS, Docker, CI/CD. This full stack developer Shopify-adjacent marketplace platform reduced seller ad management time by 47 %. 🏆As a full stack developer React Node and backend developer, I delivered a telemedicine platform for EU clinics covering remote consultations, appointment scheduling, and medical records. Stack: React, GraphQL, WebSockets, Express.js, MongoDB, Docker. Usability improvements reduced patient onboarding by 54 %. 🏆As a full stack web developer and backend developer, I built an eCommerce platform for digital products with payment processing integration via Stripe and PayPal. Stack: React, Node.js, MySQL, Swagger. Payment completion rates improved by 38 %. 🏆As a full stack developer Laravel and full stack Laravel contributor, I've supported a PHP-based backend system requiring custom code, and feature enhancements alongside JavaScript stack. 🏆As a game developer TypeScript React practitioner, I've implemented interactive dashboard visualizations and engagement mechanics applicable to betting, gambing, and 4 gamified wellness platforms. My key responsibilities as a full stack developer and web developer include building complex features, developing backend Node.js services, working closely with a UX designer and product teams, implementing API integrations, building dashboards, and improving security. As a WordPress developer with CMS integration experience, I can also handle WordPress custom code. I'm looking for startups and enterprise teams seeking a talented, experienced full stack developer for a long-term relationship and ongoing SaaS platform development, Proof-of-Concept (PoC) delivery, or MVP launches. Whether you need a mobile app developer, React developer, or a full stack developer React Node engineer fulltime, I bring the architectural thinking, excellent communication skills, and ability to troubleshoot complex platforms to level them up! 🚀

I'm Paul — a WooCommerce developer and technical architect. I build and scale high-traffic WooCommerce stores: custom development, speed optimization, and the performance work that keeps a store fast under real load. Over 10+ years I've built and maintained WooCommerce stores doing $2M+/month, and helped build a platform that grew from $0 to $80M a year. Growth is usually a technical problem in disguise — the store that can't scale is almost always held back by a setup that was never built for it. Most of my clients don't need a freelancer to knock out a task. They need someone who can see the whole system and own the result. As a WooCommerce developer I work across custom plugin development, WordPress performance, WooCommerce speed optimization, and custom checkout and subscription builds — the things off-the-shelf plugins can't do. For high-traffic stores, that sometimes means moving critical logic (inventory, pricing, order processing) out of WordPress into dedicated NestJS microservices, so WooCommerce stays the storefront and the heavy lifting happens elsewhere. What I work on: — WooCommerce development and custom builds: checkout, subscriptions, pricing logic, custom plugins. — Performance engineering: caching, database queries, and server work that keep a store fast and stable on its busiest day. — Fixes and rescues: downtime, hacks, malware, sites that fall over under traffic. — Tracking: GTM, GA4, Meta, and Triple Whale, set up so the numbers are right. — Technical leadership: acting as a de facto CTO — leading dev teams, reviewing code, owning architecture. A few examples: A store came to me profitable but constantly going down and getting hacked — messy plugins, a misconfigured server, failing Core Web Vitals. I cleaned up the server, closed the security holes, and got PageSpeed and Core Web Vitals into the green. Once it was stable and fast, the marketing could finally do its job, and revenue grew 60% that year. A high-risk US merchant needed things WooCommerce didn't do yet. I built a multi-step checkout, mini-cart, upsells and bundles back in 2018–19, plus custom inventory, forecasting, a custom ERP, and high-risk payment gateways with failing-order recovery. They became the largest store in their niche. A venture-backed company running thousands of connected devices across North America had a site that fell over at ~100 concurrent users. It wasn't traffic — no caching and a badly configured server. I rebuilt it to hold under real load. That's the pattern in most of my work: the business is ready to scale, and the setup is what's holding it back. My stack: PHP, JavaScript, React, Node.js, NestJS, and the full WooCommerce/WordPress ecosystem — plus Next.js and proper tracking (GTM, GA4, Meta, Triple Whale). For larger builds I work with a small team of engineers I've partnered with since 2015. I take on a few clients at a time. If your store is slow, breaking, or outgrowing WordPress — or you want a technical partner who owns the outcome — let's talk.