Hire the Best WinDev Mobile Specialists
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Senior Software Architect specializing in secure systems and IoT Sec solutions with 15+ years of experience. I architect and deliver end-to-end nfc solutions, from embedded firmware to cloud-based backend systems. 🎯 CORE EXPERTISE IOT Systems - NFC Solutions: Reader/Writer, HCE, Digital Wallets (Android/iOS) - Smart Cards: JavaCard, MIFARE, DESFire, NTAG,Global Platform,GP,JCOP,Secure Element - Security: PKI, FIDO, Secure Element,HSM, PCI-DSS Compliance - RFID Systems: Asset Tracking, Access Control - EMV Payment: L1/L2/L3 Kernel Development & Certification - Microcontrollers: ESP32, STM32 (WiFi/BLE, RTOS) - Firmware: Secure Bootloader, OTA Updates, Real-time Systems - Industrial Applications: POS Terminals, Vending Machines, Access Control - IoT Architecture: Sensor Integration, Remote Management Full-Stack Development - Backend: Node.js, REST APIs, Database Design (SQL/NoSQL) - Cloud Services: Firebase, AWS/Azure/GCP Deployment - Mobile: Android (NFC APIs), iOS (CoreNFC), React Native - Desktop: Qt, .NET, Cross-platform Applications - Languages: C/C++, JavaScript/TypeScript, Java, C# 💼 SIGNATURE PROJECTS ✅ ESP32 IoT Systems - Created NFC-enabled payment solution with cloud integration - Built secure firmware with OTA update capabilities - Integrated Firebase for real-time data synchronization ✅ Cross-Platform Digital Wallet - Developed mobile wallet supporting EMV contactless payments - Implemented HCE and Secure Element integration - Built Node.js backend with Firebase authentication ✅ Enterprise RFID Solutions - Designed asset tracking systems for industrial clients - Implemented access control with NFC/RFID readers - Deployed cloud-based management platform ✅ EMV Payment Terminal Solutions - Developed EMV L2 & L3 kernel for contact/contactless terminals - Achieved EMVCo certification for payment applications - Implemented secure key management and transaction processing 🔧 TECHNICAL STACK Hardware: ESP32, STM32, NFC Readers, RFID Systems Backend: Node.js, Express, Firebase, REST APIs Database: MongoDB, PostgreSQL, MySQL, Firestore Cloud: Firebase, AWS, Azure, Docker deployment Mobile: Android, iOS, React Native Desktop: Qt, .NET, Windows/Linux Security: PKI, FIDO, PCI-DSS, Secure Boot 📋 CERTIFICATIONS & STANDARDS EMVCo, PCI-DSS, PBOC, Global Platform, ISO 14443 I deliver production-ready solutions with clean code, comprehensive documentation, and ongoing support. Available for both fixed-price projects and long-term contracts.

Full Stack Developer (7 Years) | Full-Time Freelancer I provide one-stop software solutions for startups and businesses. Instead of hiring separate frontend and backend developers, I build your entire product from the ground up—from server architecture to cross-platform clients. What I Deliver: - End-to-End Lifecycle: Architectural design - Backend/API - Pixel-perfect UI - Market Release. - Cross-Platform Expansion: Seamless apps for Android, iOS, Web, Desktop, and Wear OS with high performance. - Scalable Backend Systems: Fast, reliable, and maintainable backend services powered by Rust or Kotlin for long-term product growth. - IoT & Hardware Expertise: Advanced integration for Android-based IoT clients, including Kiosk Mode, Serial Port communication, etc. - Fast Delivery: Skilled in leveraging AI agents to speed up development, reduce repetitive work, and quickly turn ideas into production-ready features. Core Tech Stack: - Frontend & Mobile: Kotlin Multiplatform, Compose Multiplatform - Backend: Axum (Rust), Ktor (Kotlin) I turn sketches into flawless, scalable apps. As a full-time freelancer, I guarantee fast, transparent communication and dedicated availability. Let’s build something great together.

✅ 13 Years Professional Experience ✅ 40+ Mobile Apps ✅ Top Rated Plus Developer Hey there! 👋 I'm Sherwin, an expert Engineer with 13+ years of experience at big tech companies. I'm experienced leading, designing and implementing core mobile features in fast-paced, technology-driven environments with worldwide impact and multiple stakeholders. I am fluent in English and have experience working with scalable and testable code, REST APIs, multiple design patterns, CI/CD pipelines and version control. 🏆 Worked in the multinational company MicroStrategy, Developed apps with over 100 million daily users such as DiDi and Kuaishou before. 🚀 Expertise in Technologies: o Native Development: Swift, SwiftUI, Objective-C, Kotlin, Java, Jetpack Compose, HarmonyOS o Cross-Platform Frameworks: React Native , Flutter o DataBase: Realm, CoreData, Firebase FireStore, Firebase Realtime Database, Supabase, RoomDatabase o Web: Flutter Web o Deploy: AWS S3, Lamda, CloudFront, EC2, OpenShot o Server Development: Python, TS ✅ My experience domains: o AI Agent o Bluetooth / Smart Watch / Camera Domain o Fitness / Health Domain o OpenAI / Assistance / Whisper o Location Tracking / Travel o Social Media/Dating Domain/Video/Audio chats o Video/Audio player processing application o Financial / Shopping Domain o Payment / In App Purchase / Apple Pay / Stripe I'm excited to bring my experience and skills to new projects and deliver high-quality work on time and within budget. Let's make great apps together! Regards, Shaolin