Most AI agents fall apart when they hit real business logic. Mine don't. As a Senior AI Developer and AI Engineer, I build autonomous systems that cut manual workflows by up to 85% — the kind your team will wonder how they ever lived without. 📩 Send your brief — I'll reply within 2 hours with a concrete action plan. 🏆 Why work with me? 🥇 Senior AI Developer and OpenAI developer with a track record of production-ready systems. 🥇 Expert AI Agent architect, agentic AI developer, and AI agent saas specialist delivering 10x ROI across SaaS, E-commerce, and Fintech. 🥇 Top-Rated AI Chatbot Developer — OpenAI developer, Bolt AI Developer, chatbot developer, and GPT-4 expert. 🥇 AI voice chatbot and AI voice assistant builder — AI voice VAPI, AI phone agent, and AI call agent systems that work 24/7. ❇️ Custom AI Agent & Autonomous Systems As a dedicated AI Developer, I build robust business logic — not wrappers. My AI Agent architecture relies on LangChain, LangGraph, and CrewAI. As an AI Developer with LangChain and Zapier expertise, I connect AI agent automation workflows to Slack, Shopify, and enterprise backends. Every AI Agent doubles as a 24/7 AI sales agent. As a Bolt AI Developer and AI web developer, I ship AI agent saas systems with front-end developer AI interfaces. As an OpenAI developer and generative AI agent specialist, the OpenAI API, GPT-4, and ChatGPT sit at the core of every AI Agent build. My AI agent python and AI agent n8n experience covers every layer of the automation stack. ❇️ AI Voice Chatbot, AI Phone Agent & AI Call Agent As an AI voice chatbot and AI voice assistant specialist, I build AI voice VAPI systems, AI phone agent flows, and AI call agent pipelines for sales, support, and AI agent real estate. My AI voice chatbot covers AI voice clone, AI voice chat, AI voice call, and WhatsApp AI chatbot channels. My AI agent real estate deployments use AI phone agent flows to qualify leads 24/7. ❇️ AI Chatbot Developer, LLM Engineering & AI Agent RAG As an AI Chatbot Developer, I build bots for WhatsApp, Telegram, and Web — GPT chatbot, OpenAI chatbot, and Telegram chatbot solutions. As a chatbot developer and AI bot developer, I integrate GPT-4, ChatGPT, and LLM backends. My AI agent rag and advanced RAG pipelines rely on Pinecone, Weaviate, and Milvus. As a Generative AI Developer, I handle LLM prompt engineering for OpenAI, Anthropic, and Llama. Medical documentation agent AI RAG is a specialist engagement for healthcare clients. ❇️ AI Agent for Sales, CRM & Digital Marketing Automation As an AI Agent architect and AI Backend Developer, I build AI sales agent and business development automation covering HubSpot marketing automation, Zoho marketing automation, digital marketing automation, YouTube automation, and social media marketing automation via API integration Python. My AI agent real estate and AI agent marketing work covers full-funnel automation pipelines. ❇️ Machine Learning, AI Deep Learning & Data Science As a machine learning expert, AI deep learning specialist, and data scientist, I build computer vision models using PyTorch and TensorFlow. My work covers Python data analysis, AI data analytics, Python web scraping, and AI classifier builds. As a Python full stack developer and AI app developer, I handle API integration Python, analytics engines, and AI model training. ❇️ AI SaaS, Full Stack AI & Enterprise As a Full Stack AI SaaS Developer, Bubble Developer AI, and iOS Developer AI, I build web application platforms and mobile AI. For Enterprises: multi-agent systems for 500k+ users and AI voice chatbot for enterprise sales. For Startups: AI Chatbot Developer and Python full stack developer shipping AI Agent and AI phone agent fast. For Deep Tech: AI deep learning, AI agent rag, and medical documentation agent AI RAG made actionable. Why should you hire me as an AI Developer? ▪ 7+ years as an AI Developer, Python developer, and machine learning expert across SaaS, Fintech, and Enterprise. ▪ $70K+ earned | 100% Job Success Score — production-ready AI systems, zero failed deployments. ▪ Expert in LangChain, LangGraph, CrewAI, OpenAI API, GPT-4, and Pinecone. ▪ 50+ AI agent and AI chatbot builds — from enterprise SaaS automation to AI agent real estate pipelines. ▪ 5+ production RAG systems and AI agent python pipelines cutting manual workflows by 85%. ▪ AI agent saas, AI phone agent, AI call agent, WhatsApp AI chatbot — cross-platform AI systems. ▪ AI developer, agentic AI developer, AI chatbot developer, AI voice assistant, AI agent RAG, generative AI agent, AI LLM developer ▪ Medical documentation agent AI RAG, digital marketing automation, HubSpot automation — full-funnel AI. ▪ AI deep learning, machine learning, and data scientist work powering every AI agent and AI SaaS build. ▪ AI Developer contracts with 100% Job Success. Looking for an expert AI Developer? Let us connect!

Hi! 🙌 I'm a Full-Stack JavaScript Developer with real-world experience building modern web and mobile products for businesses and startups 💼🚀 I help clients transform ideas into ready-made, scalable solutions that deliver results, not just "pretty code." My approach isn't just programming. I always think as a business partner, not just an implementer. 🔥 What I can build for you: ✅ Business Websites & Landing Pages ✅ SaaS Platforms & Dashboards ✅ Marketplaces & E-commerce Stores ✅ CRM / ERP Systems ✅ Web3 & FinTech Platforms ✅ Booking & Reservation Systems ✅ Admin Panels & Backoffice ✅ Social Platforms & Communities ✅ Mobile Apps (iOS / Android) ✅ Startup MVPs (from idea to launch) 🛠️ Tech Stack ⚡ Core: JavaScript • TypeScript • HTML • CSS • SCSS 🎨 Frontend: React • Next.js • Redux Toolkit • Hooks • Framer Motion Material UI • Styled Components • TailwindCSS • Axios 📱 Mobile: React Native (Expo) 🧪 Testing & API: Postman ⚙️ Backend: Node.js • Express.js • Prisma • Mongoose • JWT • Sessions 🗄️ Databases: MongoDB • PostgreSQL 🔧 Tools & DevOps: Git • Docker • Docker Compose • ESLint • Prettier • Figma 🚀 Why clients choose me: ✔️ Clean & scalable code ✔️ Pixel-perfect UI/UX ✔️ Fast communication ✔️ On-time delivery ✔️ Business-oriented mindset 💬 Ready to build something amazing? Let’s discuss your project today! 👇🔥

👋 Full-cycle Mobile App Development heaven is right here! I’m the CEO of Volpis - a custom software development agency specializing in mobile app development for both iOS and Android. With 10+ years of experience and over 100 successful projects, we help startups, mid-size businesses and enterprises build, scale, and optimize mobile apps that deliver 𝐦𝐞𝐚𝐬𝐮𝐫𝐚𝐛𝐥𝐞 𝐫𝐞𝐬𝐮𝐥𝐭𝐬. 💡 𝐖𝐇𝐀𝐓 𝐖𝐄 𝐃𝐎 We offer full-cycle Mobile App Development - from idea validation and UI/UX design to development (both front-end and back-end), QA, and post-launch support. Whether you need to build an MVP, migrate your Flutter app to native, or add new features, 𝐰𝐞’𝐫𝐞 𝐲𝐨𝐮𝐫 𝐫𝐞𝐥𝐢𝐚𝐛𝐥𝐞, 𝐥𝐨𝐧𝐠-𝐭𝐞𝐫𝐦 𝐩𝐚𝐫𝐭𝐧𝐞𝐫. 𝐎𝐮𝐫 𝐞𝐱𝐩𝐞𝐫𝐭𝐢𝐬𝐞 𝐢𝐧𝐜𝐥𝐮𝐝𝐞𝐬: 📱 Native App Development (iOS Development & Android App Development): Swift, SwiftUI, Kotlin, Java, Objective-C ⚙️ Cross-Platform Apps: Flutter or Kotlin Multiplatform (KMP) for high-performance, scalable, and fast-to-market solutions 🧩 Back-End Development: Node.js, Nest.js, Express, Firebase, MongoDB, REST APIs 🚀 App Optimization: Performance tuning, analytics (Firebase, Mixpanel, NewRelic), and crash tracking (Crashlytics) 💳 Integrations: Stripe, Payfort, Firebase, Twilio, Mapbox, Google Maps etc 🏆 𝐖𝐇𝐘 𝐂𝐋𝐈𝐄𝐍𝐓𝐒 𝐂𝐇𝐎𝐎𝐒𝐄 𝐔𝐒 ● Proven track record: 100+ successful apps with 1M+ downloads on App Store & Google Play ● Long-term partnerships: many of our clients raised funding or scaled to enterprise level after launch ● End-to-end approach: we handle everything from scratch - strategy, UX & UI design, development, documentation, deployment, and maintenance ● Quality & security: robust architecture (MVP, MVVM), secure APIs, and clean code standards 🟢 𝐎𝐔𝐑 𝐒𝐄𝐑𝐕𝐈𝐂𝐄𝐒: ● Mobile App Development: Native App Development and Cross-Platform App Development; ● Android App Development & iOS Development; ● Discovery Phase & Business Analysis; ● UX & UI Mobile App Design; ● Back-End Development for Mobile App; ● Quality Assurance & Project Management; ● Product and Technical Consulting; ● Maintenance and Support. 💼 𝐃𝐎𝐌𝐀𝐈𝐍 𝐄𝐗𝐏𝐄𝐑𝐓𝐈𝐒𝐄 We’re trusted partners in: ● Fleet Management, Logistics & Transportation ● GPS, Navigation & Mapping (Mapbox, GoogleMaps, HereMaps) ● GIS Solutions & Indoor Mapping/Navigation ● AR / Augmented Reality (ARKit, ARCore, RoomPlan, LiDAR, SceneKit) ● Social Media, Healthcare and Marketplace apps ⚡ 𝐋𝐄𝐓'𝐒 𝐁𝐔𝐈𝐋𝐃 𝐒𝐎𝐌𝐄𝐓𝐇𝐈𝐍𝐆 𝐆𝐑𝐄𝐀𝐓 If you’re looking for a reliable mobile app team that delivers on time, on budget, and beyond expectations, let’s talk. 📩 Press “Invite to Job” or message me now - and let’s turn your idea into a successful app!

I build AI agents, automations, and custom apps that run business operations. 10+ years in development. You get production-ready work, full ownership from scope to launch, and someone who doesn't drop the project halfway. Services; - AI agents that do the work people don't have time for handling inquiries, qualifying leads, booking meetings, moving data between tools, and keeping your operations running without manual input. - Automations that replace manual operations. Lead pipelines that scrape, enrich with AI, deduplicate, sync to CRM and outreach tools. Document processing workflows that turn intake forms into structured records. - Custom AI apps and SaaS. Production web apps with LLM logic, Stripe billing, dashboards, and admin panels. Send me a short description of your project. I'll get back to you with my thoughts and next steps. Keywords: AI Agent Developer, AI Automation, Chatbot Developer, Customer Support Bot, Lead Qualification Bot, AI SaaS Developer, AI SaaS MVP, Custom AI Application, LLM Integration, OpenAI API, Claude API, Anthropic, GPT, RAG, Retrieval Augmented Generation, Vector Database, Pinecone, Qdrant, pgvector, LangChain, LangGraph, n8n, Workflow Automation, Process Automation, Document Automation, Document Processing, OCR, Data Extraction, CRM Integration, API Integration, Webhook, Twilio, VAPI, Bland AI, Retell, ElevenLabs, React, Next.js, Node.js, Python, FastAPI, TypeScript, Supabase, PostgreSQL, Stripe, SaaS

🏆 Official and Certified Shopify Partner🏆 ⭐️Shopify app development expert and Tech Leader with 10+ years of commercial Shopify web development experience⭐️ My Shopify app developer achievements and skills: ▶️ Shopify app developer with 65+ public Shopify apps successfully listed on the Shopify App Store, currently driving growth for more than 125000 active merchants daily. ▶️ Dedicated Shopify app developer behind 50+ private and custom apps, tailoring custom business logic for enterprise-level brands. ▶️ As an experienced Shopify app developer and Shopify API Developer - designed robust Shopify embedded application architectures, handling 500k+ Shopify API requests per minute during Black Friday / Cyber Monday. ▶️ Migrated 20 legacy systems to Shopify Remix, Node.js, TypeScript, Prisma ORM, Redis, and BullMQ as a full stack developer / python developer, slashing client AWS/Heroku infrastructure costs by 50%. ▶️ Built a custom Checkout Extensibility app utilizing Shopify Admin API and Shopify Storefront API, boosting brands' AOV by 15-22% via smart upsells. ▶️ I am a results-driven Shopify app developer who delivered around 40 custom integrations by connecting Shopify APIs correctly with ERP/CRM systems like Odoo, Salesforce, custom ERPs, industrial designer software via REST API with 0% data loss. ▶️ App developer who built an inventory sync app for 100000+ SKUs, leveraging Liquid and webhooks to reduce multi-location updates to less than 2 seconds. ▶️ Go-to Shopify app developer for code audits; refactored 20+ Shopify apps to improve architecture, ensuring 100% compliance and flawless App Store submission on the first try. Now, my Shopify web development experience in statistics and numbers: ⚙️ Shopify developer - I launched 100+ high-end Shopify stores built on premium Shopify themes like Dawn, Impulse, Prestige, Horizon, Be Yours, with focus on website design, mobile-first approach and conversion rate optimization. ⚙️ I am a data-driven Shopify developer CRO specialist, consistently improving client conversion rates by 90-120% through strategic UX enhancements / checkout optimization and other ways. ⚙️ Shopify web development expert who engineered 50+ cutting-edge Shopify headless solutions on Hydrogen and Next.js - delivering ultra-fast storefront architectures. ⚙️ Shopify web developer - successfully completed 20 Shopify projects with 100000+ product SKUs and complex shipping setups. ⚙️ Shopify developer speed and Shopify developer SEO marketing expert, achieving 95+ Core Web Vitals scores and improving shopify speed and page load times by 75% for more than 40 D2С and B2B brands. ⚙️ Versatile Shopify backend developer and WordPress Shopify developer - have made over 20 WooCommerce to Shopify migrations with zero SEO traffic drop and less than 30 minutes downtime. 🚀 Services I offer as a Shopify app developer & react developer - Shopify app development - building public Shopify apps with guaranteed shopify app store approval and App Store submission. - Custom Shopify apps and integrations - dedicated Shopify API Developer for high-performance private app solutions (f.e. affiliate marketing programs) - API Connectivity - Shopify API integration to connect Shopify APIs with enterprise CRMs, ERPs, third-party logistics via REST API. - Modern tech stack - using Shopify Remix, Node.js, TypeScript, and Prisma ORM following Shopify best practices. - Frontend customization - combining Liquid with custom APIs for interactive storefront features and app extensions. - Harnessing the Shopify Admin API and Shopify Storefront API for deep data sync and custom Shopify integrations. - Code audits - troubleshooting and upgrading legacy code to meet modern Shopify app development standards. 🚀 Web developer services (Shopify developer expert) - Shopify developer and wordpress developer moving stores to Shopify from WooCommerce, Magento, BigCommerce, or custom platforms. - premium theme development - Shopify web development focused on premium themes like Focal or Prestige, deep theme customization, and custom layouts. - headless ecommerce - Shopify developer building headless storefronts with Hydrogen, Next.js, and custom frontends. - conversion rate optimization - Shopify developer CRO setups, refactoring UX/UI to improve checkout rates and store sales. - Shopify speed optimization and Shopify developer SEO marketing configuration for high Core Web Vitals and Google rankings. - Expert knowledge of Shopify Liquid, HTML, CSS, JavaScript & Shopify APIs - Full shopify management, catalog setup, and automated shopify dropshipping architecture. 𝐃𝐫𝐨𝐩 𝐦𝐞 𝐚 𝐦𝐞𝐬𝐬𝐚𝐠𝐞 with a quick summary of what you're building or a link to your current store. Even if you don't have a final spec ready yet, we can jump on a call, discuss the logic, and figure out the roadmap together. Looking forward to building something solid.

⭐️ Top Rated Plus - Top 3% of talent on Upwork ✅ 6+ years of experience 🚀 Built a SaaS platform that served 50,000+ users ⚙️ Improved API response times by 45% 📉 Reduced server costs by 38% 🔐 Implemented secure auth systems used by 30,000+ active accounts 🛒 Built e-commerce platforms with $2M+ processed payments Hey there! 👋 I’m a Full Stack Developer with 6+ years of commercial experience as a web developer, react developer building high-load web platforms, scalable APIs, modern front-ends, and cross-platform mobile apps. I’ve successfully delivered 80+ web projects as a Full Stack Developer, working across industries like e-commerce, SaaS, FinTech, EdTech, and HRTech. As a web developer and react developer, I focus on performance, clean architecture, and business-ready solutions. 🔧 Core Expertise as Full Stack Developer / Web Developer / React Developer ✅ Front End Development as Full Stack Developer and React Developer React.js, Next.js, TypeScript, JavaScript (ES6+), Redux, Tailwind, Material UI, built 50+ dashboards, 30+ client-facing UIs, and 20+ admin panels as a react developer and web developer. ✅ Backend Development as Full Stack Developer and Web Developer Node.js, NestJS, Express.js, TypeScript, built 100+ REST APIs, authentication systems, background jobs, queues, and real-time services as a Full Stack Developer and web developer. ✅ Database Architecture PostgreSQL, MongoDB, Redis, designed 40+ optimized databases, managed millions of records, and improved query speed by 35%. ✅ WordPress Development as WordPress Developer Custom themes, SEO optimization, WooCommerce, custom plugins, built 25+ production websites as a wordpress developer. ✅ Mobile App Development as Mobile App Developer React Native, published 15+ apps with real-time sync, offline support, and API integrations. ✅ Cloud Infrastructure AWS (EC2, S3, Lambda), Docker, Kubernetes, CI/CD, deployed 60+ production environments as a Full Stack Developer and web developer. 🎯 What I Do Daily as a Full Stack Developer / Web Developer / React Developer ✅ Work full-time as a Full Stack Developer on SaaS platforms with 1,000+ active daily users ✅ Build advanced dashboards as a react developer with <120ms TTFB ✅ Create fast-loading websites as a web developer with 90+ Google PageSpeed scores ✅ Develop platforms that handle 500,000+ requests per day as a Full Stack Developer ✅ Build performant SPAs and SSR apps as a react developer ✅ Deliver production-ready websites as a wordpress developer ✅ Publish stable applications as a mobile app developer 💼 Industries I Work In as Full Stack Developer / Web Developer: - 📦 E-commerce platforms as a Full Stack Developer and web developer - 💳 FinTech systems as a Full Stack Developer - 📊 SaaS products as a react developer and Full Stack Developer - 🏫 EdTech and HRTech solutions as a web developer - 🧩 Corporate websites as a wordpress developer - 📱 Mobile-first products as a mobile app developer Why Clients Choose Me When clients need a Full Stack Developer, web developer, or react developer, they work with me because I bring: ✅ 6+ years as a Full Stack Developer ✅ 80+ delivered projects as a web developer and react developer ✅ 15+ long-term business clients ✅ Clean, scalable code ✅ Fast delivery and clear communication Let’s build your product with a Full Stack Developer who thinks as a web developer, builds as a react developer, and delivers as a Full Stack Developer focused on real business results

Stop losing users to clunky, slow-loading interfaces, research shows 53% of users will abandon a web app if it takes more than three seconds to load! 🚀 I am a Senior full stack developer and Senior Engineer with 8 years of experience building elite, high-performing web apps. As a full stack developer and specifically a full stack developer react node, I architect scalable SaaS platforms. When you need a full stack developer react node, you get a versatile web developer, skilled front-end developer, and robust back-end developer. Here is how my full stack developer react node expertise ensures your website and web app succeed: Reduced page loads by 42% for a flagship saas product as lead full stack developer, bridging the gap between a ux designer and a front end developer react. Scaled a react and node.js web app for 100k+ users, proving the value of a dedicated full stack developer react node utilizing the mern stack. Boosted retention by 30% by overhauling website ia, showing exactly why your MVP needs a reliable full stack developer react node. 💻 Architecture & Front-End Excellence 💡 As a dedicated full stack developer, I leverage mern architecture, next.js, and react to build robust solutions. A top-tier full stack developer react node combines the vision of a ux designer and a designer to ensure exceptional ia. I am a react developer and front-end developer integrating a high-converting exaplainer video or demo video to boost saas sales and saas marketing. A successful web developer and full stack developer masters the MERN stack, javascript, vue.js, and angular for comprehensive saas platforms. Every web app I build as a full stack developer react node relies on node.js, nestJS, react, and next.js to deliver an ai-powered experience. A full stack developer react node knows react is the key to scalable ui. As a full stack developer I guarantee every saas mvp is flawlessly executed by a true full stack developer react node,. 📱 Mobile App Development & Full Stack Power ⚙️ As a mobile app developer and full stack developer react node, I create every native app with precision. Using react native and react native mobile, your mobile app is seamless. A full stack developer knows a react native mobile deployment requires a strong back-end developer managing firebase and supabase. As a react developer and full stack developer react node, every native app and web app I build integrates flawlessly with node.jss and next.js. Hire a full stack developer react node and get a react developer who masters supabase to firebase, ensuring your react ecosystem thrives. Every saas business needs a full stack developer react node who is both ui-focused and backend-focused. 📈 E-commerce, Backend & Niches 🔥 Building a custom shopify storefront, shopify website, or shopify platform? A full stack developer react node brings essential php and laravel skills. As a back-end developer and full stack developer, I leverage laravel, python, and php, ensuring advanced laravel routing for complex b2b software. A full stack developer react node excels in e-commerce, integrating woocommerce and shopify. My full stack developer react node experience covers everything from a landing page to a healthcare app, clinic saas, and fitness saas using rest api and postgresql. As an ai workflow engineer and front-end layout engineer, I engineered a security automation platform, cold email software, and live commerce saas. 🚀 Next-Level Web Solutions 🌐 As a full stack developer, I deliver a cost-controlled MVP using webflow customization / react integration and aws. My skills build a robust business management app and scalable MVP management system. Whether creating a browser extension, deterministic fsm intake system, or live basketball betting dashboard, I am the full stack developer react node for you. Deploying a multi-dealer inventory marketplace and web-based casino game utilizing redis, websocket, and java spring proved my wordpress developer capabilities. My webflow customization / integration drives social integration and onboarding flow enhancement. I build an ai-powered / ai-savvy mvp with css grid, ai, and next.js. Need a full stack developer react node to scale? My expertise as a full stack developer react node and full stack developer is unmatched. A web developer mastering ia, mern, and webflow ensures your demo video, woocommerce exaplainer video, and webflow perfectly boost mvp sales and SaaS marketing. When you hire a full stack developer, you need an engineer who breathes react and SaaS. My journey as a full stack developer react node guarantees that whether we are scaling a SaaS platform or a bespoke web app, your react architecture remains pristine. A dedicated full stack developer react node is the ultimate asset for your SaaS. As a Full Stack Developer React Node, I empower your business to thrive. Hire a full stack developer react node to scale your SaaS, MERN web app, and react native mobile app today!

Need a mobile app built that holds up after launch? I lead mobile app development that ships production-ready iOS and Android apps that survive real users - several are live on the App Store and Google Play right now. I'm Oleksandr, founder and lead engineer at Kultrix, an AI and Mobile App Studio, working from Lviv. Most of our work is React Native mobile app development, plus the AI features and backend that make an app actually useful. I run engagements as a long-term technical partner, not a vendor you chase for updates - which is why several engagements have run 16 months to 4+ years. You get senior engineering ownership from first call to store release: clear scope, milestone-based delivery, honest timelines, and a lead who is accountable for the result. As founder and lead engineer, I make sure the mobile app development gets done right, not just fast. WHAT WE BUILD - Full mobile app development in React Native and Expo, from idea to store release - a cross-platform iOS and Android app from one codebase, typically a launched MVP in 6-10 weeks. With a senior React Native developer leading, we cover MVP development, App Store and Google Play submission, and everything in between. - AI integration inside mobile apps - chat, image and vision analysis, and conversational voice (OpenAI and Anthropic Claude), already shipped in live AI mobile apps. Clean API integration so the AI feature feels native, not bolted on. - Rescue and refactor of React Native apps that broke under real users - performance, crashes, and stability work to get an existing app back to store-ready. - Backend when your app needs more than screens: Node.js, NestJS, Python and FastAPI, PostgreSQL, MongoDB, Firebase, and Supabase (including auth and RLS). WHO IT IS FOR - Starting from scratch: a clear path from idea to a launched MVP in 6-10 weeks, built by a team that has shipped to both stores. - Already have an app: mobile app development help with new features, performance, and stability - whether you need an iOS developer, an Android developer, or both. - Want to add AI: a chat, vision, or voice feature shipped into your live cross-platform app through careful AI integration, scoped so it ships fast and stays maintainable. HOW WE WORK You talk to the people building your app, not a sales layer. We agree on scope and milestones up front, you see working builds early and often on TestFlight and internal tracks, and you get honest status instead of silence. When something is harder than estimated, you hear it early - with options, not surprises. The goal is a stable app you can grow on, and a codebase your next mobile app developer can read without a rewrite. VERTICALS WE KNOW We have shipped mobile app development work across health and wellness, nutrition, and fitness (calorie tracking, meal analysis, AI coaching), fintech and Web3 (payments, Plaid, Polygon on-chain apps), SaaS (Stripe billing and dashboards), and internal tools and logistics (warehouse and operations systems). If your app lives in one of these spaces, we have built and launched something close to it. RESULTS - An AI nutrition tracker - React Native meal and calorie analysis with Anthropic Claude and OpenAI - live on both the App Store and Google Play, owned end to end (mobile, API, and admin). - An AI fitness app on a Python and FastAPI backend with OpenAI, live on the App Store and Google Play. - A conversational-voice health app built with React Native, Expo, and Claude. - A Web3 scratch-card app on Polygon with Plaid integration, live on Google Play, plus a daily-quotes app on the App Store. - A warehouse operations system that runs 4x faster for 100+ employees. - Long-term mobile app development engagements kept for 16+ months and 4+ years - the clearest signal that this work lasts. OUR STACK React Native, Expo, TypeScript for cross-platform iOS and Android; Node.js, NestJS, Python and FastAPI, PostgreSQL, MongoDB, Firebase, and Supabase on the backend; Stripe, in-app purchases, push notifications, and WebSockets for real product features; and AI APIs (OpenAI and Anthropic Claude) for chat, vision, and voice. This is the full toolkit for modern mobile app development and AI integration, from first commit to a stable app on the App Store and Google Play. Send me your idea or your existing app and you will get back a clear, honest breakdown - what to build first, what can wait, and a realistic timeline for the mobile app development. No pressure, no jargon, just a straight answer from the lead who would own the work. Oleksandr - founder and lead engineer, Kultrix (AI and Mobile App Studio).

Reliable .NET Full Stack Developer for Scalable Web Solutions I’m a .NET Full Stack Developer who delivers production-ready features on time, keeps development cost-efficient, and builds scalable web solutions that grow with your business. As a Senior .NET Full Stack Developer, I design and develop secure, high-performance applications using .NET and Angular, focusing on clean architecture, scalability, and long-term maintainability. I’m a .NET Developer who aligns technical decisions with business goals. Every solution I deliver as a .NET Full Stack Developer is production-ready, reliable, and built for real users. Experience & Credentials Certified Senior .NET Full Stack Developer 8+ years of commercial experience as a .NET Developer and Tech Lead 30+ completed projects on Upwork 100+ delivered projects with my Intelvision team (last 5 years) 100% Job Success | 1900+ hours | $100K+ earned Trusted .NET Developer for Visoplan, ING+, Jincom, Kiflo, and more When clients need a reliable .NET Full Stack Developer, they come back. Core Role: .NET Full Stack Developer As a .NET Full Stack Developer, I handle frontend, backend, APIs, databases, cloud infrastructure, and DevOps. As a .NET Developer, I ensure security, performance, and scalability from day one. I work as: .NET Full Stack Developer for SaaS platforms .NET Full Stack Developer for enterprise systems .NET Full Stack Developer for MVP and startup products .NET Developer for long-term system growth Core Technologies (.NET Full Stack) .NET Full Stack .NET Developer (ASP NET Core, Web API, SignalR) Angular (enterprise SPA, NgRx, RxJS) Node.js (for hybrid architectures when needed) Every project is led by a .NET Full Stack Developer, not a generalist. Backend & Architecture (.NET Developer Expertise) As a .NET Developer, I build backend systems using: RabbitMQ, Docker, Kubernetes, Redis, GraphQL, SignalR, Elasticsearch, Hangfire, MediatR, Quartz NET, Akka NET, Autofac, Dapper, NHibernate, Swagger, FluentValidation, Serilog, NLog This is what separates a .NET Full Stack Developer from a basic coder. Frontend Development (Angular) As a .NET Full Stack Developer, I pair backend power with modern UI development: Angular, TypeScript, SPA, PWA, NgRx, RxJS, Angular Universal, NG-ZORRO, Tailwind CSS, MUI, Ant Design, Lighthouse optimization A strong .NET Developer always delivers a strong frontend. Cloud, DevOps & CI/CD (.NET Full Stack) Azure, AWS, Docker, Kubernetes, GitHub Actions, GitLab CI, Azure DevOps A real .NET Full Stack Developer owns deployment, scaling, and monitoring. Security & Authentication (.NET Developer Focus) Auth0, IdentityServer4, Azure AD B2C, OAuth 2.0, JWT, Azure Key Vault, AWS IAM Security is mandatory for any .NET Full Stack Developer. Business & API Integrations Stripe, Xero, QuickBooks, Microsoft Graph API, Salesforce, SAP, Dynamics As a .NET Developer, I build systems that integrate with real business tools. Testing & Quality xUnit, NUnit, Moq, MSTest, Karma, Jest A professional .NET Full Stack Developer ships tested code. Industry Experience as .NET Full Stack Developer SaaS platforms FinTech systems PropTech and ConTech Logistics and supply chain Custom enterprise solutions Each domain was delivered by a .NET Full Stack Developer with real production experience. Why Clients Choose Me as a .NET Full Stack Developer Deep backend expertise as a .NET Developer Strong Angular frontend delivery Clean architecture and scalability Business-oriented mindset Long-term partnership approach Whether you need an MVP, SaaS, PoC, or enterprise system, you need a .NET Full Stack Developer, not just a coder. Let’s Build Your Product If you’re looking for a reliable .NET Full Stack Developer, an experienced .NET Developer, and a partner who delivers on time, let’s talk. Your product deserves a .NET Full Stack Developer who understands scale, security, and growth.

🏆 Why I'm a Top-Rated Full Stack Developer & .NET Developer 8+ years as a Full Stack Developer and .NET Developer, 60+ web apps shipped for US, UK and EU clients
$60k+ earned on Upwork as a C# Developer and .NET Developer, 100% Job Success Score
 As a Full Stack Developer, I've shipped 40+ releases combining React, Angular and ASP.NET Core
 As a C# Developer, I cut API response times by 45% and infrastructure costs by 30% for a fintech client
As a .NET Developer, I migrated 3 legacy monoliths to .NET Core microservices, +70% deployment speed 💥 Recent win — as a Full Stack Developer and C# Developer, I rebuilt a logistics platform using .NET Core, Angular and MySQL, cutting order processing time by 55% and lifting client retention by 22%. 🟢 Most business platforms are slow, hard to scale and expensive to maintain. With 8+ years as a .NET Developer, C# Developer and Full Stack Developer, I architect scalable web developer solutions on .NET, Angular, React and Python stacks that turn technical debt into growth 🟢 ⭐️⭐️⭐️⭐️⭐️ "She's an outstanding .NET Developer and Full Stack Developer. Reliable, communicative, and delivers clean, production-ready C# code every time." 🎯 WHY CLIENTS CHOOSE ME AS A FULL STACK DEVELOPER I'm a Full Stack Developer, .NET Developer and C# Developer with full-cycle ownership — from database architecture and API design to pixel-perfect frontends. As a C# Developer, I write clean, testable code following SOLID principles, and as a Full Stack Developer I make sure the entire product actually works for your users. ✔️ .NET Core & C# — as a .NET Developer and C# Developer: scalable ASP.NET Core APIs, background services, .NET MAUI apps
 ✔️ Frontend — React, Angular, Vue.js, jQuery, built for speed and clean UX
 ✔️ Full Stack Development — as a Full Stack Developer, connecting .NET, Node.js and Python backends to JavaScript frontends
 ✔️ Web Developer Services — as a web developer, WordPress, Laravel and PHP sites alongside custom .NET apps
 ✔️ Database Architecture — MySQL, SQL Server, API Integration for data-heavy systems
 ✔️ Cloud & DevOps — Azure, AWS, Docker, CI/CD, supporting .net full stack developer and full stack developer react deployments 📊 RESULTS 🔶 Fintech Platform: as a .NET Developer and C# Developer, -60% transaction errors, 99.9% uptime via a full .NET Core rebuild
 🔶 E-commerce Marketplace: as a Full Stack Developer, React + .NET Core APIs, +28% checkout conversion, 3x page load speed
 🔶 Healthcare SaaS: as a senior .net developer, HIPAA-compliant rebuild, -40% manual admin work ⚙️ TECH STACK C#, .NET, .NET Core, .NET Framework, .NET MAUI, ASP.NET, React, Angular, Vue.js, Node.js, JavaScript, TypeScript, Python, PHP, Laravel, WordPress, HTML5, CSS 3, jQuery, Bootstrap, MySQL, SQL Server, Git, Azure, AWS, Docker, Software Architecture & Design, Agile Software Development, Desktop Application development 💼 EVERY PROJECT AS A FULL STACK DEVELOPER INCLUDES ▪️ Clean, well-documented C# and .NET code with automated testing
 ▪️ Direct communication, just a senior C# Developer / .NET Developer working on your project 
▪️ Ongoing support after launch as your long-term Full Stack Developer and .NET Developer partner 🏭 INDUSTRIES Fintech · Healthcare · E-commerce · Logistics · SaaS · Real Estate · EdTech 🔎 ALSO EXPERIENCED AS react developer · python developer · java developer · blockchain developer · mobile app developer · wordpress developer · full-stack web developer · python full stack developer · wordpress full stack · full stack developer react · c# .net developer · senior fullstack developer · .net full stack developer · senior .net developer · .net core developer · c developer · cs cart developer · qnap integration · c# wpf · c# angular · c# unity · javascript fullstack · fullstack web developer · full stake developer · c# game developer · full-stack development Each project covers a real client engagement, twice over: react developer dashboard + rebuild; python developer API + script; java developer module + fix; blockchain developer audit + integration; mobile app developer release + update; wordpress developer site + migration; full-stack web developer scope; python full stack developer work; wordpress full stack rebuild; full stack developer react integration; c# .net developer contract; senior fullstack developer judgment; .net full stack developer discipline; senior .net developer oversight; .net core developer debugging; c developer fixes; cs cart developer migrations; qnap integration fixes; c# wpf builds; c# angular dashboards; c# unity prototypes; javascript fullstack proofs of concept; fullstack web developer delivery; full stake developer projects; c# game developer credits; full-stack development results. 🚀 LOOKING FOR A RELIABLE FULL STACK DEVELOPER OR .NET DEVELOPER? 👉 Hire a proven .NET Developer, C# Developer and Full Stack Developer. 📅 Last updated: 10.07.2026