Full-Stack Web Developer | React + .NET | Corporate Background I'm a full-stack developer with hands-on production experience building web applications at scale. About Me: I'm currently completing my Associate's degree in Computer Science at Da Vinci College Dordrecht while working as a developer. I've invested over 1400 hours in real-world development, focusing on clean code, scalability, and delivery excellence. My Expertise: Frontend Development: • React & Svelte (modern component architecture) • TypeScript (type-safe, maintainable code) • Responsive UI design & performance optimization Backend Development: • .NET/C# (microservices, REST APIs) • PHP/Laravel (when needed) • Database design (PostgreSQL, SQL Server) DevOps & Deployment: • Docker containerization • CI/CD pipelines (GitHub Actions) • Linux server management • Automated testing & deployment What I'm Best At: ✓ Complex backend architectures ✓ Smooth deployment workflows ✓ Problem-solving under pressure ✓ Working with solo and teams projects Work Style: • Communicative and proactive • Detail-oriented with clean code standards • Comfortable with agile workflows • Happy to explain my approach Current Availability: Part-time freelance (10-15 hrs/week) while maintaining quality

Overall 6+ years of Industry Experience and Presently working as a Full-stack developer for Web-based applications using PHP and MERN stack. My goal for working on Upwork is to create value in the client’s business and earn the trust of the client. I follow best practices for Web app development e.g. automated unit testing, static code analysis, code reviews, software builds, etc. Please check some of the work in the Portfolio Section. Key Technical skills: - • PHP, codeignator, Zend • Angular, JavaScript, jQuery, ReactJS, Redux, D3.js, XML, AJAX, CSS3, HTML5, Bootstrap • MySQL, Postgres, Mongo DB • Node.js, Nest.js, Vue.js • Ngnix, Apache Web Server, nuxtuWSGI • ExtJs, Sencha Touch & Sencha Architect • Heroku, AWS, GitHub Looking forward to becoming an asset to your team. Regards,

Full-stack JavaScript and Solidity developer with 8+ years of experience in developing responsible and highly scalable web applications. Wesley is adept at understanding the requirements of clients and delivering projects accordingly. He uses latest technologies and modern design patterns to deliver high quality products.

I am a professessional JavaScript Developer and I have 7 years experience of React, React Native and Redux. I am very familiar with webpack, babel and es6 in React. And also I have enough experience with javascript frameworks such as angular.js, vue.js, bootstrap and jquery. I can develop and integrate back-end with node.js/express.js, meteor.js and php frameworks such as laravel, codeignitor, and shopify. I am also developing mobile apps using React Native, Swift and Android Studio in iOS and Android platforms. Here are my skill sets: ✅ React/React Native (WebPack, Babel, ES6, Redux, Sagas) ✅ Angular.js/Vue.js/jQuery/BootStrap/HTML5/CSS3/SASS ✅ Laravel, CodeIgniter, Ruby on Rails, Node.js/Express.js, Meteor.js, Shopify, WordPress ✅ iOS and Android app development (Swift, Objective-C, Java, Cocoa) I always satisfy clients with on-time, on-budget, good-delivery and I can communicate clearly in fluent English. I am full-time developer and I can work in your timezone. Thank you

🏆 𝘾𝙧𝙤𝙨𝙨-𝙋𝙡𝙖𝙩𝙛𝙤𝙧𝙢 𝙈𝙤𝙗𝙞𝙡𝙚 𝘿𝙚𝙫𝙚𝙡𝙤𝙥𝙚𝙧 | 𝙍𝙚𝙖𝙘𝙩 𝙉𝙖𝙩𝙞𝙫𝙚 | 𝙀𝙭𝙥𝙤 | 𝙁𝙞𝙧𝙚𝙗𝙖𝙨𝙚 Are you looking for a reliable Mobile App Developer who delivers high-performance, scalable, and pixel-perfect apps for both iOS and Android? You're in the right place! 📱 What I Do: I specialize in building cross-platform mobile applications using React Native and Expo, backed by powerful Firebase cloud solutions. From concept to App Store/Google Play deployment, I handle the full mobile development lifecycle with clean, maintainable code and a user-first mindset. 💼 My Core Expertise: ✅ React Native & Expo — Smooth, native-feel apps for iOS & Android from a single codebase ✅ Firebase — Real-time Database, Firestore, Authentication, Cloud Functions & Push Notifications ✅ REST API & GraphQL Integration — Seamless backend connectivity ✅ Redux / Context API / Zustand — Scalable state management solutions ✅ React Navigation — Intuitive multi-screen navigation experiences ✅ UI/UX Implementation — Pixel-perfect designs using Tailwind, NativeWind & Styled Components ✅ App Store & Google Play Deployment — End-to-end publishing & release management ✅ TypeScript — Type-safe, production-grade codebases ✅ Third-Party Integrations — Stripe, Google Maps, Twilio, OneSignal & more 🎯 Industries I've Served: 🛒 E-Commerce & Marketplace Apps 💬 Real-Time Chat & Messaging Apps 🏥 Healthcare & Telemedicine Apps 🎓 EdTech & E-Learning Platforms 🏋️ Fitness & Lifestyle Apps 💰 FinTech & Payment Gateway Apps ⚙️ My Development Process: 🔹 Discovery — Understanding your vision, goals & requirements 🔹 Planning — Architecture design, tech stack selection & timeline 🔹 Development — Agile sprints with regular updates & demos 🔹 Testing — Unit testing, device testing & QA across iOS & Android 🔹 Deployment — App Store & Google Play submission & optimization 🔹 Support — Post-launch maintenance & feature enhancements 🌟 Why Hire Me? ✔️ 100% Client Satisfaction — Your success is my priority ✔️ On-Time Delivery — I respect deadlines and keep you updated ✔️ Clean & Scalable Code — Built for long-term growth ✔️ Clear Communication — Daily/weekly progress reports ✔️ Bug-Free Guarantee — Thorough testing before every delivery ✔️ Long-Term Partnership — I don't just build apps, I build relationships 🛠️ Tech Stack at a Glance: React Native • Expo • Firebase • TypeScript • JavaScript • Redux • REST API • GraphQL • Node.js • MongoDB • Git • Figma • NativeWind • App Store Connect • Google Play Console 📩 Let's Build Something Amazing Together! Drop me a message and let's discuss your project. I'm available for short-term tasks, long-term contracts, and ongoing app maintenance. "Your idea deserves a world-class app — Let's make it happen!" 🚀

Welcome to my page. I am Kevin, an experienced full-stack developer with a broad and versatile coding skill set. My 9 years` experience makes me more confident and able to work with projects of any difficulties. Since I work as a freelancer, I delivered many projects and services to businesses all around the world. It's my passion, and my mission to provide high-quality services to my customers and build successful projects.

I'm a Software Developer specialised in Java and Spring Boot, with experience building and modernising backend systems, cloud applications and complete SaaS products. I have worked on software projects for organisations such as Rabobank, Omoda and Port of Rotterdam, as well as building complete applications for smaller businesses. My experience ranges from enterprise backend development and application migrations to designing and developing products from scratch. Besides my professional software development work, I am the founder and developer of Loyaltree, a SaaS loyalty platform that I built from the ground up. This has given me hands-on experience with the complete product lifecycle: architecture, backend and frontend development, cloud deployment, integrations, launching a product and improving it based on real customer feedback. My main technologies include Java, Spring Boot, React, React Native, TypeScript, PostgreSQL, Kafka, Google Cloud and AWS. I enjoy working with businesses and founders who have a problem or software idea and need someone who can translate it into a practical, reliable and scalable solution.

I am a Senior DevOps and AI/ML Engineer with 8 years of experience in designing and deploying robust cloud-native applications and backend systems. My expertise encompasses Python, JavaScript/TypeScript, Docker, Kubernetes, and AWS. I specialize in creating seamless MLOps workflows and scalable system designs that support innovative AI-powered products. My approach combines a strong infrastructure foundation with product-oriented thinking, ensuring reliable applications from architecture to production. Whether you're looking to enhance your existing systems or build new capabilities from the ground up, I have the skills and insights to drive your project to success. Let's collaborate to bring your vision to life and achieve impactful results.

I am a frontend developer with a solid foundation in HTML, CSS, JavaScript, React, and modern development tools like Bootstrap, Sass/SCSS, Tailwind and Webpack. I specialize in building responsive, user-friendly web applications that prioritize clean, maintainable code and seamless user experiences. Having completed a comprehensive frontend bootcamp, I am actively expanding my expertise through hands-on portfolio projects and continuous learning. I enjoy solving problems, exploring new technologies and engaging web solutions. Beyond coding, I am curious, adaptable, and enthusiastic about learning. I love meeting new people, exchanging ideas, and embracing new experiences that challenge me to grow both personally and professionally.

𝐏𝐑𝐎𝐅𝐄𝐒𝐒𝐈𝐎𝐍𝐀𝐋 𝐒𝐔𝐌𝐌𝐀𝐑𝐘 Senior Full Stack Developer and Mobile Developer with 7+ years building production React, Next.js, Node.js, NestJS, React Native, and Expo applications scaled to 1M+ users. Deep expertise across the modern JavaScript/TypeScript stack: React 18/19, Next.js 14 App Router, Node.js, NestJS, Express.js, and Prisma ORM on the backend; React Native and Expo (iOS and Android) on mobile; and AWS (EC2, Lambda, S3, RDS, CloudFront) for cloud infrastructure. Specialized in AI/LLM integration - shipping production OpenAI (GPT-4o, GPT-5) and Anthropic Claude (Sonnet, Opus) integrations, RAG pipelines on pgvector/Pinecone, LangChain-based agent workflows, and vector database systems. Full-stack TypeScript throughout. PostgreSQL, MongoDB, MySQL, and Redis for data and caching. Daily AI-augmented development with Claude, ChatGPT, Cursor, GitHub Copilot, and Windsurf. Proven impact: 40% inference cost reduction, 55% latency improvement, 35% API latency reduction, 20% throughput improvement. Available for freelance React/Next.js development, React Native/Expo mobile app development, Node.js/NestJS backend APIs, AWS cloud architecture, and AI/LLM integration (OpenAI, Anthropic Claude, RAG) engagements. 𝐖𝐇𝐀𝐓 𝐒𝐄𝐓𝐒 𝐌𝐄 𝐀𝐏𝐀𝐑𝐓 👉𝐅𝐮𝐥𝐥-𝐒𝐭𝐚𝐜𝐤 𝐑𝐞𝐚𝐜𝐭 + 𝐍𝐞𝐱𝐭.𝐣𝐬 + 𝐍𝐨𝐝𝐞.𝐣𝐬 + 𝐍𝐞𝐬𝐭𝐉𝐒 + 𝐓𝐲𝐩𝐞𝐒𝐜𝐫𝐢𝐩𝐭 - End-to-end delivery across React 18/19 and Next.js 14 (App Router, RSC, Server Actions) frontends, Node.js + NestJS + Express.js + Prisma ORM backends, PostgreSQL and MongoDB databases, and AWS cloud infrastructure. Full-stack TypeScript, single-language ownership from database schema to React component. 👉𝐑𝐞𝐚𝐜𝐭 𝐍𝐚𝐭𝐢𝐯𝐞 + 𝐄𝐱𝐩𝐨 𝐌𝐨𝐛𝐢𝐥𝐞 𝐃𝐞𝐯𝐞𝐥𝐨𝐩𝐦𝐞𝐧𝐭 (𝐢𝐎𝐒 + 𝐀𝐧𝐝𝐫𝐨𝐢𝐝) - Shipped React Native and Expo apps to App Store and Google Play Store with offline-first sync, biometric auth, push notifications (FCM, APNs), deep linking, in-app purchases, EAS Build, EAS Update, and native modules in Swift and Kotlin. One React Native app reached 1M+ users; another reached 40% of total platform traffic within 6 months. 👉𝐀𝐈/𝐋𝐋𝐌 𝐈𝐧𝐭𝐞𝐠𝐫𝐚𝐭𝐢𝐨𝐧 (𝐎𝐩𝐞𝐧𝐀𝐈, 𝐀𝐧𝐭𝐡𝐫𝐨𝐩𝐢𝐜 𝐂𝐥𝐚𝐮𝐝𝐞, 𝐑𝐀𝐆, 𝐋𝐚𝐧𝐠𝐂𝐡𝐚𝐢𝐧) - Production OpenAI GPT-4o and Anthropic Claude API integrations with streaming, function calling, and structured outputs. RAG pipelines on pgvector, Pinecone, and Weaviate. LangChain and LlamaIndex agent workflows. Vector database and embedding systems. Delivered 40% LLM cost reduction and 55% latency improvement in production. 👉𝐀𝐖𝐒 𝐂𝐥𝐨𝐮𝐝 𝐀𝐫𝐜𝐡𝐢𝐭𝐞𝐜𝐭𝐮𝐫𝐞 & 𝐃𝐞𝐯𝐎𝐩𝐬 - AWS EC2 auto-scaling, Lambda, S3, CloudFront, RDS (PostgreSQL and MySQL), Bedrock, ALB, ECS/Fargate, CodePipeline. Docker containerization, CI/CD pipelines (GitHub Actions, CircleCI), Nginx, blue-green deploys, zero-downtime migrations. 15% infrastructure cost reduction and 99.9% uptime records. 👉𝐏𝐫𝐨𝐯𝐞𝐧 𝐚𝐭 𝟏𝐌+ 𝐔𝐬𝐞𝐫 𝐒𝐜𝐚𝐥𝐞 - React + Next.js + Node.js + NestJS + PostgreSQL + AWS systems scaled to 1M+ active users. Distributed Redis caching (3x traffic absorption), auto-scaling AWS EC2, containerized Docker deployments, and PostgreSQL query optimization. 👉𝐃𝐚𝐢𝐥𝐲 𝐀𝐈-𝐀𝐮𝐠𝐦𝐞𝐧𝐭𝐞𝐝 𝐃𝐞𝐯𝐞𝐥𝐨𝐩𝐦𝐞𝐧𝐭 𝐖𝐨𝐫𝐤𝐟𝐥𝐨𝐰 - Claude (Sonnet, Opus, Claude Code), ChatGPT (GPT-4o, GPT-5), Cursor, GitHub Copilot, and Windsurf used daily for React/Next.js/Node.js/TypeScript code generation, refactoring, debugging, test scaffolding, and LLM integration testing. Strong code review discipline maintained. 👉𝐑𝐞𝐦𝐨𝐭𝐞-𝐍𝐚𝐭𝐢𝐯𝐞, 𝐀𝐬𝐲𝐧𝐜-𝐅𝐫𝐢𝐞𝐧𝐝𝐥𝐲 - 5+ years async delivery across US, Canada, and European time zones. Strong written communication, self-directed delivery, and structured