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I’m S M Nazmul Hasan, CEO of Kolpolok Limited, trusted by cybersecurity companies, SaaS providers, and VPN startups in 65+ countries. Over the past decade, I’ve delivered VPN solutions that power millions of daily connections. I build scalable, reliable VPN platforms that drive real business growth. 💡𝗦𝗼𝗹𝘂𝘁𝗶𝗼𝗻𝘀 𝗜 𝗗𝗲𝗹𝗶𝘃𝗲𝗿 𝗳𝗼𝗿 𝗬𝗼𝘂 ➡️ End-to-End VPN App Development: ✔ Multi-platform VPN apps for iOS, Android, Windows, macOS, Fire TV, and browsers ✔ Fully white label vpn solutions with 𝗰𝗼𝗺𝗽𝗹𝗲𝘁𝗲 𝘀𝗼𝘂𝗿𝗰𝗲-𝗰𝗼𝗱𝗲 𝗼𝘄𝗻𝗲𝗿𝘀𝗵𝗶𝗽 ✔ Seamless in-app purchases, user authentication, and multi-language support ✔ Intuitive UI/UX design focused on conversion and retention ➡️ White-Label VPN SDK Integration: ✔ WL VPN SDK integration with scalable custom backend solutions ✔ Integration with PureVPN White Label SDK and other leading providers ✔ Ready-to-launch SDKs customized to your brand and user requirements ✔ Full technical support for integration, testing, and deployment ➡️ Multi-Protocol Backend Infrastructure: ✔ Support for OpenVPN, WireGuard, IKEv2, Shadowsocks, VMess, VLESS, IPsec, OpenConnect, Singbox compatible infrastructure ✔ Scalable VPN admin panel dashboards with user management, and analytics. ✔ Real-world traffic optimization, load balancing, and redundancy configurations ✔ Compliance-ready architecture aligned with GDPR, SOC2, and ISO standards 💡𝗪𝗵𝘆 𝗖𝗹𝗶𝗲𝗻𝘁𝘀 𝗖𝗵𝗼𝗼𝘀𝗲 𝗠𝗲 I don’t just build apps, I build VPN ecosystems tailored to your business model. ✔ Total Code Ownership – You own the complete source code from day one ✔ Business-First UX – Apps designed for real users, not just developer functionality ✔ Security & Compliance – ISO-certified workflows, and robust encryption standards ✔ Scalable Architecture – Built to grow with your user base, handling thousands of concurrent connections ✔ Rule-Based Routing & Split Tunneling – Optimized configurations for China and restricted regions ✔ Complete Documentation – Clean code documentation ✔ Manual Training & Technical Support – Hands-on guidance for your internal team ✔ Fast Delivery – Fast responses, and transparent progress updates ✔ 𝗧𝗼𝗽-𝗥𝗮𝘁𝗲𝗱 𝗣𝗹𝘂𝘀 𝗨𝗽𝘄𝗼𝗿𝗸 𝗖𝗼𝗻𝘁𝗿𝗮𝗰𝘁𝗼𝗿 ✔ 𝟭𝟬𝟬%+ 𝗝𝗼𝗯 𝗦𝘂𝗰𝗰𝗲𝘀𝘀 𝗥𝗮𝘁𝗶𝗻𝗴 ✔ 𝟵𝟬% 𝗔𝗯𝗼𝘃𝗲 𝗥𝗲-𝗵𝗶𝗿𝗲 𝗥𝗮𝘁𝗲 📝𝗣𝗿𝗼𝘃𝗲𝗻 𝗧𝗿𝗮𝗰𝗸 𝗥𝗲𝗰𝗼𝗿𝗱 Delivered 150+ projects in 65+ countries across 5 continents ✔ Developed VPN apps with millions of downloads and 4.9+ star average ratings across Google Play, App Store, and Trustpilot ✔ Supported long-term client growth with performance-focused infrastructure enhancements 👤𝗪𝗵𝗼 𝗜 𝗦𝘂𝗽𝗽𝗼𝗿𝘁 & 𝗪𝗼𝗿𝗸 𝗪𝗶𝘁𝗵 ✔ Startups, SaaS, and tech firms launching their first VPN product to enter this booming market ✔ Entrepreneurs and VPN resellers seeking high-performance white-label apps with fast deployment ✔ Agencies and consultancies adding VPN to their service portfolio for recurring revenue streams 💡𝗥𝗲𝗰𝗲𝗻𝘁 𝗙𝗼𝗰𝘂𝘀 𝗔𝗿𝗲𝗮𝘀 ✔ Open Connect, WireGuard, OpenVPN, Sing Box optimization for faster connections and lower battery usage ✔ Advanced obfuscation techniques to bypass censorship firewalls ✔ Payment gateway integrations for subscription-based VPN monetization ✔ VPN reseller admin panels with automated user and license management ✔ Multi-protocol hybrid backend design for global coverage and redundancy 𝗟𝗲𝘁’𝘀 𝗕𝘂𝗶𝗹𝗱 𝗬𝗼𝘂𝗿 𝗩𝗣𝗡 𝗕𝘂𝘀𝗶𝗻𝗲𝘀𝘀 You’re not just hiring a VPN developer. You’re partnering with an expert who understands the technical, business, and security dimensions of building VPN products that scale. If you’re ready to deploy a secure, scalable, and revenue-generating VPN solution under your brand, send me a message. I’ll respond within 24 hours with a tailored roadmap to bring your VPN vision to life. 𝑰𝒏 𝒂𝒅𝒅𝒊𝒕𝒊𝒐𝒏 𝒕𝒐 𝒇𝒖𝒍𝒍-𝒔𝒕𝒂𝒄𝒌 𝑽𝑷𝑵 𝒔𝒐𝒍𝒖𝒕𝒊𝒐𝒏𝒔, 𝑰 𝒉𝒆𝒍𝒑 𝒇𝒐𝒖𝒏𝒅𝒆𝒓𝒔 𝒂𝒏𝒅 𝒑𝒓𝒐𝒅𝒖𝒄𝒕 𝒕𝒆𝒂𝒎𝒔 𝒃𝒓𝒊𝒏𝒈 𝒆𝒂𝒓𝒍𝒚-𝒔𝒕𝒂𝒈𝒆 𝒊𝒅𝒆𝒂𝒔 𝒕𝒐 𝒍𝒊𝒇𝒆 𝒘𝒊𝒕𝒉 𝒊𝒏𝒕𝒖𝒊𝒕𝒊𝒗𝒆 𝒅𝒆𝒔𝒊𝒈𝒏 𝒂𝒏𝒅 𝒍𝒆𝒂𝒏 𝒅𝒆𝒗𝒆𝒍𝒐𝒑𝒎𝒆𝒏𝒕 𝒔𝒕𝒓𝒂𝒕𝒆𝒈𝒊𝒆𝒔. ✔ MVP Development for Fast Launch Agile MVP's tailored to validate your core concept, reduce time-to-market, and attract user traction—without unnecessary features or costs. ✔ UI/UX Design that Converts Crafting modern, user-focused interfaces for mobile and web apps—built to engage, retain, and grow your audience from day one. ✔ Fleet & VTS Tracking – Real-time GPS tracking and fleet optimization systems ✔ IoT Solutions – Smart, connected platforms with real-time automation ✔ AI Integration – Predictive, data-driven features to power growth Whether you're testing a new product or refining an existing one, I ensure your app is not just functional—but user-loved and market-ready. Let’s connect to launch your brand and lead the market today!

I started coding at a very young age and have now spent 17+ years building real software products used by thousands of users worldwide. Over the last several years I’ve focused heavily on Flutter AI-powered applications backend systems and scalable mobile architecture. I'm an Anthropic Claude Certified Architect (Foundations) with expertise in designing production-grade AI applications including agentic architectures Model Context Protocol (MCP) tool integration prompt engineering context management and Claude Code workflows. Today I use AI-assisted development daily with Claude Code OpenAI Codex and modern agentic workflows to build products dramatically faster while maintaining clean architecture and long-term scalability. I specialize in building high quality cross-platform mobile applications for iOS and Android using Flutter and Dart with production-ready backend systems realtime infrastructure and AI-powered experiences. I’ve worked with startups YC-backed companies SaaS platforms AI products ecommerce systems healthcare apps fintech platforms social apps and automation systems. My experience includes both fast-moving MVP development and large scale production applications. One of my biggest projects was building the mobile app for Cartpanda a YC-backed ecommerce platform from Brazil where I worked as a Senior Mobile Engineer and helped scale a complex production application used by real businesses. I also build AI-powered systems and agentic applications using OpenAI Claude and Gemini with modern LLM workflows. 🚀 Core Skills & Technologies 📱 Mobile & Flutter Flutter SDK, Dart, Riverpod, Bloc, FlutterFlow, Rive animations, realtime systems, WebSocket integrations, offline-first architecture, Firebase Cloud Messaging (FCM), RevenueCat, Superwall, payment systems, subscription platforms, native iOS and Android integrations, App Store Connect and Google Play Console ⚙️ Backend & APIs NodeJS, TypeScript, FastAPI, Supabase, Firebase, PostgreSQL, REST APIs, realtime backend systems, authentication systems, Supabase RLS, Clerk Auth, Stripe integration, Dockerized backend services, scalable API architecture and admin dashboards 🌐 Web & Frontend NextJS, React, Tailwind CSS, shadcn/ui, Vercel, responsive frontend systems, SaaS platforms, realtime dashboards, internal business platforms and AI-powered web applications 🤖 AI & Automation OpenAI, Claude, Gemini, multimodal AI systems, AI agents, AI chatbots, LangChain, RAG pipelines, OCR workflows, vector search systems, MCP workflows, AI document processing systems, n8n and Make automation 🎙️ Voice AI & Realtime AI Retell AI, Vapi, LiveKit, Deepgram, ElevenLabs, realtime voice agents, conversational AI systems, speech-to-text pipelines, text-to-speech systems, low latency audio streaming, AI phone agents and AI receptionist workflows ☁️ DevOps & Infrastructure Docker, Docker Compose, DigitalOcean, Ubuntu servers, Nginx, Redis, Celery, GitHub Actions, Firebase Hosting, Cloudflare DNS, CI/CD workflows, Linux deployment and scalable cloud infrastructure

Top Rated Plus Shopify App Developer with 9+ years of Shopify experience, $70K+ earned, 141 completed projects, and published apps on the Shopify App Store. I build production-ready Shopify apps, checkout extensions, Hydrogen storefronts, Shopify Plus integrations, and automated workflows for ecommerce brands, startups, and agencies. Published Shopify Apps: - Blog CTA - Real-Time Find & Replace - Simple Product Rating - Torosachi Subscription What I Can Build: - Custom Shopify apps using Remix, Polaris, Prisma, and Shopify CLI - Shopify Admin API, Storefront API, GraphQL, and REST API integrations - Shopify Billing API and subscription systems - Checkout UI Extensions and post-purchase extensions - Shopify Hydrogen and Oxygen storefronts - Shopify webhooks and workflow automation - Shopify theme development and Liquid customization - Figma to Shopify theme conversion - Shopify speed optimization and Core Web Vitals improvements - Third-party API integrations - Shopify Plus, Flow, B2B, Markets, and advanced storefront architecture Why Clients Hire Me: - Top Rated Plus on Upwork - 141 completed projects with 130+ reviews - Published Shopify App Store developer - Strong ownership from planning to deployment - Clean, scalable, production-ready code - Fast response time and clear communication - Long-term collaboration mindset Tech Stack: Shopify, Remix, Hydrogen, Polaris, Liquid, React, Node.js, TypeScript, GraphQL, Prisma, Next.js, REST APIs, Laravel If you need a Shopify expert who can build reliable apps, integrations, storefronts, or automation workflows, send me a message or invite me to your job.

I have 9+ years of experience in Linux/Windows Server/System Administration, System Security Analysis and hardening, Virtualization (VMware, Proxmox, Hyper-V) Management, Website, Cloud Server, Video Streaming Server, Database System performance optimization for speed, CDN, Email System, Anti-SPAM and DNS Administration. Skills: - Virtualization Platforms: VMware, Proxmox, OpenStack, OpenNebula, Xen, KVM, LXC, Docker - Cloud: AWS, DigitalOcean, Google Cloud, AliBaba Cloud, Microsoft Azure Cloud - Performance Optimization: Linux OS, Apache, Nginx, MySQL, MariaDB, Website, WordPress - Expertise in security solutions like Firewalls, Anti-Spam Solutions, VPN (OpenVPN, WireGuard, OpenConnect, WebSock), Security Gateways, IDS/IPS (Suricata, Snort, pfSense, OPNsense, Palo Alto, SOPHOS UTM). - Expert in Email Servers and Anti-Spam Gateways (Postfix, Exim, Barracuda, Zimbra, Proxmox Gateway, SOPHOS) - Disaster Recovery, DLP, Data Backup solutions. - Database Administration and tuneup for higher performance & query. - Knowledge in IP-PBX, VoIP, WebRTC, RTMP, Wowza - BigBlueButton & Scalelite Custom Video Conferencing, Video streaming solutions with LMS integration. - Expertise in WordPress, Website Performance/Security Optimization. - Hosting Control Panels: cPanel, VestaCP, DirectAdmin etc. - Knowledge of Cross-platform mobile app development using React-Native. - Desktop software development using Java and React-Native-Windows - Integrate any hardware with software using SDK (Java, PHP) I can adapt myself with new technology, products as per company needs. I can develop new products and drive excellent growth and positive revenue. I'm fluent/native in the English language. I'll deliver your project on time with quality and excellence.

⭐⭐⭐⭐⭐ ✅ 18+ years in Unity, AR/VR, game, app, web and more. ✅ I provide coding, designs, models, animations, everything. ✅ Hourly rate is negotiable! 🚀🚀🚀

Hi there, I'm a Software Engineer. I am working on Windows and Web Development. I can help you to build your application. I value my time, and I know you do the same way. So let's do business now! Cheapest and Reliable provider!!! Support is available 24/7. My services are: ● C#, C ● .Net Windows & Web Development. ● .Net MVC, .Net Web Form, ADO.Net, VB .Net. ● .Net Web API, RESTful API ● .Net Core, .Net MAUI. ● Layer Architecture. ● Crystal Report, SSRS (RDLC Report) ● ERP HR Module, Banking Remittance Solution. ● Umbraco CMS. ● IIS Hosting Server. ● Azure web hosting, Azure DevOps, Docker. ● JavaScript, jQuery. ● Kendo UI-(Telerik). ● HTML, CSS. ● Angular 10 (Basic), Blazor (Basic). ● PSD to HTML ● MS SQL, PostgreSQL. ● SignalR. ● Unit Testing (SonarQube) ● GitHub, GitLab ● Agile (Jira, Trello). You will get: Quality Work 100% satisfaction Full-time support 100% accuracy Always available for customer orders. ORDER NOW TO GET YOUR JOB DONE WITH 100% ACCURACY! ❉❉❉ Thank You ❉❉❉