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I am a professional freelancer with THIRD PARTY LIABILITY INSURANCE for over two and a half million dollars, so you are in safe hands. I am Microsoft Certified Trainer, Office 365, GCP, AWS, and Azure Expert. Honored as Microsoft Most Valuable Professional in Azure area. I cover architecting, security, administrating, and migration of all three major clouds – Azure, AWS, and GCP. Apart from the main area of Cloud expert in the field of infrastructure servers Windows Server 2003-2016, Microsoft Active Directory, Hyper-V Private Cloud, IIS, System Center, SQL. Private Cloud, System Center, Hyper-V, Open Stack Expert, and all Microsoft products Expert. Linux Server administrator. I am the holder of certificates: • pSeries AIX UNIX Support • First Certificate in English • PRINCE2 Practitioner • Microsoft Certified: Azure Administrator Associate • Microsoft® Certified Solutions Expert: Cloud Platform and Infrastructure • Microsoft® Certified Solutions Associate: Cloud Platform • Microsoft® Certified Solutions Expert: Productivity • Microsoft® Certified Solutions Expert: Data Management and Analytics • Microsoft® Certified Solutions Associate: Windows Server 2016 • Microsoft® Certified Solutions Associate: Windows 10 • Microsoft Specialist: Configuring Windows Devices • Microsoft Specialist: Architecting Microsoft Azure Solutions • Microsoft Certified Solutions Developer: Azure Solutions Architect • Microsoft Specialist: Developing Microsoft Azure Solutions • Microsoft® Certified Solutions Expert: Data Platform • Microsoft Specialist: Implementing Microsoft Azure Infrastructure Solutions • Microsoft® Certified Solutions Associate: Office 365 • Microsoft® Certified Solutions Expert: Private Cloud • Microsoft® Certified Solutions Expert: Messaging • Microsoft® Certified Solutions Associate: SQL Server 2012/2014 • Microsoft® Certified Solutions Associate: Windows Server 2012 • Microsoft® Certified Solutions Expert: Server Infrastructure • Microsoft® Certified IT Professional: Enterprise Administrator on Windows Server 2008 • Microsoft® Certified Solutions Associate: Windows Server 2008 • Microsoft® Certified Technology Specialist: Windows Server 2008 Applications • Microsoft® Certified Technology Specialist: Windows Server 2008 Network • Microsoft® Certified Technology Specialist: Windows Server 2008 Active Directory • Microsoft® Certified Technology Specialist: Microsoft Exchange Server 2010

Do you have a slow SQL Server query, a broken SSIS package, or a complex stored procedure that needs fixing? I am a Senior T-SQL Developer and Database Engineer with extensive experience in high-transaction environments where business logic resides within the database ("Thick Database" architecture). I specialize in troubleshooting, optimizing, and developing robust database solutions. Whether you need a quick fix for a performance issue or a long-term partner for backend development, I can help. HERE IS HOW I CAN HELP YOU: SQL PERFORMANCE TUNING I will analyze your slow queries and Execution Plans to reduce runtimes from minutes to seconds. I specialize in indexing strategies and code refactoring. T-SQL DEVELOPMENT & BUG FIXING I can write or fix complex Stored Procedures, Functions, Triggers, and Views. I have a strong background in L3 Support, so I am used to finding root causes quickly. ETL & DATA INTEGRATION (SSIS) I can build, fix, or modify SSIS packages. I have experience integrating data from various sources, including Oracle and third-party APIs. MIGRATION & DATA INTEGRITY Need to move data or update your schema? I write safe, reliable migration scripts to ensure your data remains consistent. WHY WORK WITH ME? - I am communicative and transparent (years of experience in direct client support). - I focus on long-term stability, not just quick patches. - I am available for ad-hoc tasks and part-time cooperation. Tech Stack: Microsoft SQL Server, T-SQL, SSIS, Oracle (Integration), SSMS, Git. Let's discuss how I can improve your database performance today!

Hello World I am a game developer generalist, tools and bot coder with 10+ years of freelancing experience. I've worked solo and in teams on 2D/3D, VR, single and multiplayer games. In recent years I've specialized in Unreal Engine but I've also used Unity and other tech in the past. Besides that I also know my way around automation (Bots for websites, games, desktop programs, mobile apps) and music related tools (Midi/Arduino). If you have interesting project then don't hesitate to contact me. cheers

I build and maintain SaaS platforms where payments and billing actually have to work — subscriptions, multi-tenant systems, and Stripe integrations that survive production. If you're launching a subscription product, scaling a multi-tenant SaaS, or you've inherited a complex Laravel/Symfony app that needs a reliable hand to keep it running — that's exactly what I do. ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ WHAT I DO BEST 💳 Stripe & Subscription Billing Full subscription lifecycle — checkout, upgrades, downgrades, cancellations, webhooks, and Stripe Connect for marketplaces and platform payouts. 🏢 Multi-tenant SaaS Tenant isolation with separate databases, scalable architecture, and clean separation between domain and infrastructure. 🏗️ Enterprise & Long-lived Systems Long-term work on large Symfony (DDD) products — the kind of complex, business-critical systems that need someone who understands them deeply, not just quick fixes. 🔌 APIs & Integrations REST and GraphQL APIs, third-party integrations, and backends designed to be consumed, not patched. 🔐 Data Protection Sensitive user data encrypted at rest, role-based access control, OAuth, and token authentication done properly. 🛠️ Long-term Support & Maintenance I take over existing Laravel/Symfony apps, modernize what's fragile, and stay on as the person you call when something breaks. ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ HOW I WORK 8+ years building production systems with PHP. I've spent ~5 years on a single large Symfony product (v5–v7) built around Domain-Driven Design — so I know what it takes to grow and maintain a complex system over years, not just ship and leave. Equally strong with Laravel, and comfortable across the stack: Go for performance-critical services, TypeScript where it fits, Vue/Nuxt on the frontend. • I read your codebase before I touch it — no cowboy changes • I fix the cause, not just the symptom • Clear communication, no disappearing mid-project • I understand the business, not only the code ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ TECH Backend PHP, Laravel, Symfony (DDD), REST & GraphQL APIs Payments Stripe (subscriptions, Connect, webhooks) SaaS Multi-tenancy, queues, real-time (Pusher/Reverb) Other Go, TypeScript, Vue/Nuxt, PostgreSQL, Redis, Docker ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ If you've got a subscription product, a multi-tenant SaaS, or a Laravel/Symfony system that needs ongoing care — send me a message. Happy to take a look at what you're working with.

🚀 𝐓𝐡𝐞 𝐭𝐨𝐩 𝟏% of elite talent in Full-Stack Web Development & Tech Leadership 🏆 CTO at Onix-Systems | 25+ Years of Experience | Enterprise Solutions Architect & AI Product Pioneer ⚡ My goal is simple — transforming raw business ideas into highly profitable, production-ready, and market-leading digital products. 🙋‍♂️ Click Hire or Invite Senior Full Stack Developer & Full-Stack Web Development Expert 💻 WHAT YOU AND YOUR TEAM GET Senior Full Stack Developer & CTO - 25+ years of driving technology strategies, designing bulletproof system architectures, and leading senior engineering teams. Full-Stack Web Development Master's - high-performance web application development utilizing React, Node.js, and PHP to build scalable SaaS, FinTech, and Enterprise software. AI & Automation Systems Innovators - custom LLM applications, RAG pipelines, and intelligent workflow automations seamlessly integrated into your infrastructure. 📊 ACHIEVEMENTS IN NUMBERS (BUSINESS & SYSTEM IMPACT) 25+ years, 50,000+ engineering hours, 200+ successful launches delivered as a Senior Full Stack Developer and tech leader across global industries. Full-Stack Web Development for Enterprise & SaaS Platforms: Engineered and launched custom AI-powered SaaS platforms that scaled to millions of active users with 99.99% operational uptime. Accelerated product development cycles by 40% by deploying optimized React component libraries and agile workflows. Backend Architecture & API Engineering (Node.js & PHP): Reduced server infrastructure costs by 50% by migrating legacy monoliths into scalable microservices using Node.js, NestJS, and PHP. Optimized heavy data-processing pipelines, reducing database latency by 70% via tailored PostgreSQL, MongoDB, and MySQL schemas. AI App Development & Workflow Automation: Developed and integrated proprietary OpenAI GPT, Claude, and Gemini models into operational CRMs, increasing client workflow efficiency by 180%. Successfully deployed secure, HIPAA-compliant healthcare applications and high-security FinTech platforms with built-in Stripe / PayPal integrations. 🎯 WHERE WE DELIVER (CORE EXPERTISE) As a Full Stack Developer & Solution Architect: I handle the full cycle of Full-Stack Web Development, defining technical roadmaps, designing scalable web applications, and ensuring bulletproof cyber-security protocols. As a Front-End Development Expert: Crafting pixel-perfect, highly responsive user interfaces using React, Next.js, TypeScript, Vue.js, and Angular to ensure maximum conversion rates and premium UX. As a Back-End Development Authority: Designing ultra-fast APIs and core services with Node.js (Express/NestJS), PHP, Python (FastAPI/Django), and modern Serverless Stack architectures. As a Cloud & DevOps Engineer: Implementing enterprise-grade cloud deployments via AWS, Google Cloud, and Azure, utilizing Docker, Kubernetes, and automated CI/CD pipelines. 🛠 TECH STACK & ARCHITECTURE ECOSYSTEM Frontend Suite: React, Next.js, TypeScript, Tailwind CSS, Vue.js, Angular, Responsive Web Design. Backend Core: Node.js, NestJS, Express.js, PHP, Python, FastAPI, Django. Databases & Caching: PostgreSQL, MongoDB, MySQL, Redis. APIs & Global Integrations: REST APIs, GraphQL, Webhooks, Stripe, PayPal, Twilio, SendGrid. Cloud & DevOps Platform: AWS (Amazon Web Services), Google Cloud, Azure, Docker, Kubernetes, Jenkins, GitHub Actions CI/CD. 🧠 DEEP INDUSTRY EXPERIENCE AI & SaaS Startups: Rapid MVP development, RAG pipelines, AI chatbots, and predictive analytics tools. FinTech & E-commerce: High-load payment gateways, customized checkout solutions, compliance, and ledger systems. Healthcare & PropTech: Automated workflow systems, secure patient portals, CRM platforms, and real-time data visualization dashboards. Enterprise Automation: Heavy B2B platforms, marketplaces, and cross-platform integrations. ⚡ HOW WE WORK TOGETHER (THE CTO VALUE) Strategic Discovery: As a CTO, I align your business goals, success metrics, and timeline constraints before writing a single line of code. Architecture Blueprinting: We map out the core database schemas, React frontend components, and Node.js / PHP API flows to ensure long-term scalability. Agile Iteration: Backed by the senior engineering powerhouse at Onix-Systems, we deliver high-velocity sprints with predictable, production-ready releases every 2 weeks. DevOps & Launch: Secure deployment across AWS/GCP/Azure with ongoing tech partnership and proactive optimization based on product metrics. Looking for an elite Senior Full Stack Developer, CTO, and Full-Stack Web Development team to turn your complex concept into a world-class, scalable web platform? Let’s connect! Send over your project brief, scope, or existing codebase notes, and I’ll provide a high-level strategic roadmap for your next big launch. ☎️

Most people schedule a meeting to discuss the problem. I'd rather just solve it and send you an update. That's how I've worked across 70+ projects on Upwork - taking ownership of an area, keeping it running, and flagging issues before they become problems. No status meetings, no hand-holding, no chasing. Just results. 🏆 Top Rated | 98% Job Success Score | 70+ projects Over the past 3+ years I've run content and SEO operations for affiliate companies, marketing teams, and founders - maintaining their websites, publishing workflows, content systems, and everything that keeps the machine running. I don't just complete tasks. I maintain systems. Give me ownership of an area, tell me the deadline, and I'll handle it. If I have questions, I'll send a message. If something needs flagging, you'll hear from me before it becomes a problem. That's it. ⚙️ What I run → Content operations at scale - managing publishing, updates, QA, and ranking maintenance across multi-site portfolios (100+ domains experience) → WordPress & CMS management - publishing workflows, plugin maintenance, site QA, content updates → SEO operations - on-page optimization cycles, keyword-driven content updates, ranking tracking, structured content revisions → Affiliate & iGaming content - casino reviews, sportsbook rankings, bonus updates, compliance checks, payment method verification → AI-assisted workflows - using AI tools to speed up content QA, bulk updates, and repetitive operations → Process documentation - SOPs, Loom walkthroughs, workflow setup in ClickUp / Airtable / Monday → WooCommerce operations - product management, order workflows, store maintenance 📈 What I've delivered → Managed content operations across 100+ affiliate websites - ranking updates, content QA, SEO maintenance, publishing workflows → Ran structured SEO content cycles across iGaming and affiliate platforms with weekly delivery → Built full SOP libraries with Loom walkthroughs - handed over documented systems, not just completed tasks → Audited a 2M+ article site - identified 172 critical issues, mapped a phased recovery plan, zero prior access to the CMS → Maintained WooCommerce operations including product catalog, orders, and custom add-on management I work best in long-term, async setups with clear ownership and no micromanagement. Weekly delivery, written updates, zero unnecessary calls. That's when I do my best work - and when you'll stop worrying about that part of your business. Available for ongoing and part-time contracts.