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I'm a software engineer who's been building web and mobile products since 2013, and I lead the team at NUS Technology. My background is hands-on engineering, not slideware. I came up building high-traffic Ruby on Rails systems and complex web applications, and I still stay close to the architecture, the hard technical calls, and the code that has to hold up in production. Over 12+ years I've grown that into a team that does it at scale: 90+ people co-located in one Ho Chi Minh City office, including 75+ engineers (60+ web, 15+ mobile) plus QA, BAs, PMs, and designers. So when you work with me, you get an engineer who understands your problem at the technical level, and a full team to deliver it. WHERE I GO DEEP - Ruby on Rails: high-traffic systems, complex domains, API design, and legacy codebases most people won't touch - Frontend: React, Next.js, Vue.js, TypeScript, building interfaces that stay fast and maintainable as they grow - Cloud & DevOps: AWS, Google Cloud, Heroku, Docker, CI/CD, monitoring, and tuning systems for cost and scale - eCommerce: Shopify, Saleor, Spree, custom headless builds, complex integrations, and migrations off legacy platforms like Magento WHAT MY TEAM COVERS Everything above, at scale, plus the full stack around it: - Backend beyond Rails: Node.js, PHP (Laravel, Symfony), Python (Django, Flask), REST and GraphQL APIs - Mobile: native (Swift, Kotlin) and cross-platform (React Native, Flutter), including the hard stuff like offline-first sync, BLE sensor processing, and frame-accurate video - QA, business analysis, project management, and UI/UX design THE PROBLEMS I LIKE SOLVING - Operations platforms: the central system that runs bookings, payments, teams, hardware, and compliance when off-the-shelf tools stop coping. Software modeled on how your business actually works, not the other way around. - Legacy rescue: inheriting a system nobody wants to touch and making it safe to change again, without a risky rewrite. We've taken an 11-year-old codebase from timeout-or-fail to 3-7 second responses. - Deep integrations: the ones Zapier can't handle and SaaS avoids. Payments, logistics, identity, hardware, compliance-grade audit trails where failure isn't an option. - Performance: finding the real bottleneck and fixing it. We've cut infrastructure costs 50% and pulled 95th-percentile response times down to 500ms on live products. PROOF - Top Rated Agency on Upwork, 98%+ Job Success Score since 2013, 4.8/5.0 average rating - $10M+ in project value delivered - Clients who've stayed 5-10+ years, some since 2014 HOW I WORK - I think like a technical co-founder, not a contractor. I'll tell you when something is a bad idea before you build it. - I surface technical debt and scaling bottlenecks before they escalate, not after. - Clear communication across time zones. We're GMT+7, with strong overlap for AU and workable hours for US/EU. - Long-term thinking. I build systems that scale, not quick hacks that break six months later. WAYS TO WORK WITH ME 1. Build a core operations platform: internal tools, SaaS, workflow automation, complex integrations, replacing a stack of fragmented tools with one system 2. A dedicated engineering team: backend, frontend, mobile, and QA as an extension of yours, often for years 3. Product and MVP builds: idea to launch, fast but not fragile If you want someone who understands the engineering, challenges your assumptions, and can put a real team behind it, let's talk.

I am a professional embedded software engineer with more than 12 years of experience. My current areas of expertise are IoT Applications & Embedded Systems Design, including embedded hardware/software. 𝐌𝐘 𝐒𝐊𝐈𝐋𝐋𝐒: - Know about MCU: Nordic, Silicon Labs, AVR, PIC, ESP, TI CC32xx, ESP32, Qualcomm QCC51xx, etc. - Have experience in programming languages such as C/C++, C#, Java - Solid knowledge of standard interfaces such as I2C, SPI, UART, and CAN. - Have experience using debugging tools such as Segger Jlink, CAN bus analyzer, and Logic analyzer. - IoT devices with wireless connectivity such as LTE, CAT-M1, NB-IoT, LoRa/LoRaWAN, BLE, WIFI, NFC - Good experience in AWS Service, AWS IoT, AWS Shadow, and AWS Jobs. - Good experience in Battery Management Systems based on BQ products from TI. - Good experience with Audio Codec chips. - Experience with AI/ML on Edge Impulse with nRF Connect - True wireless earbuds, headsets and speakers, Bluetooth ® LE Audio standard from Qualcomm: QCC5141, QCC5171, QCC5181,... We have worked with wearable devices and medical devices: - ECG 1, 3, 12 leads with ADS1292, ADS1293, ADS1298 - EEG with ADS1299 - Body temperature with MAX302025, MAX30208 - PPG with MAX86178, MAX86178 - SPO2 with OB1203, MAX32664 sensor hub - Vital signal with AFE4950 - OTA firmware update via Bluetooth/WIFI End-to-End Embedded & Hardware Solutions I provide complete product development services — from concept and design through prototyping, firmware, and production — for IoT, wearables, medical, and consumer electronics. Hardware & PCB Design - Multi-layer PCB design for high-reliability, high-performance systems - High-speed design: USB 2.0, HDMI 2.0, DDR3/DDR4/LPDDR4, PCIe, NAND Flash, Ethernet (up to 10GBase-T1), PoE++ - Microcontrollers & SoMs: ARM Cortex-M3/M4 (STM32, ESP32, Nordic nRF52/53/91); custom boards for Raspberry Pi CM4, iMX8, Jetson Nano/Xavier/Orin, RK3588/3568, TI AM6254 - Power & analog: DC-DC (Flyback, Boost, Buck, LDO), BLDC/servo motor control, high-resolution ADC/DAC, audio circuits, and battery management (BMS) - DFM/DFA and EMC/EMI compliance, with certification support (CE, FCC, FDA-ready) - Tools: Altium Designer, KiCAD, Eagle, EasyEDA, OrCAD; SolidWorks and Inventor for 3D/enclosure design Firmware & Connectivity - Embedded software in C, C++, Python, and Qt, with RTOS integration and low-power optimization - Custom driver development and communication protocols: QSPI, I2C, SPI, RS485/RS232, CAN, Modbus (TCP/IP/RTU) - Connectivity stacks: BLE, Wi-Fi, NFC, LoRa/LoRaWAN, LTE, CAT-M1, NB-IoT, GSM (3G/4G) IoT platforms: MQTT, ThingsBoard, AWS IoT, Blynk; secure OTA updates, device provisioning, and cloud integration - Robotics: ROS/ROS2 for AGV, AMR, and 6-axis robot applications - Embedded UI/UX: Figma, TouchGFX, LVGL AI & Cloud Integration - Edge AI/ML deployment (Edge Impulse, TensorFlow Lite) - Predictive maintenance and anomaly detection for IoT/IIoT - Cloud integration with AWS, Azure, and Google Cloud - Cross-platform mobile apps (Android/iOS) and web dashboards for monitoring and analytics Product Leadership - Proven experience leading cross-functional teams in startup environments - End-to-end project management across design, fabrication, and procurement for cost-efficient, on-time delivery - Strong troubleshooting and research skills for electrical evaluation, testing, and design optimization 🔑𝐊𝐄𝐘𝐖𝐎𝐑𝐃𝐒: Embedded Design, Hardware Design, Firmware Development, Mobile App Integration, IoT Device, Medical Device Design, Embedded Systems, Real-time Operating Systems (RTOS), Microcontroller Programming, Sensor Integration, Wireless Communication (Bluetooth, Wi-Fi), Low Power Design, Wearable Devices, Firmware Architecture, Embedded Software, Device Drivers, System-on-Chip (SoC), PCB Design, Signal Processing, IoT Platforms, Cloud Integration, Mobile App Development, Web Portal Design, Healthcare Technology, Remote Monitoring, Data Security, Telemetry, ARM Cortex, ESP32, Device Connectivity, Embedded Prototyping, Human-Machine Interface (HMI), Medical Device Compliance, Mobile-Connected Devices, IoT Security, BLE, Firmware Debugging, Connectivity Solutions, Edge Computing, Smart Devices, Industrial IoT.

I help startups and businesses build high-quality products from MVP to production-ready with a dedicated team behind me to move fast and ship reliably. Beyond mobile, I bring a strong focus on AI-native development: using tools like Claude, Cursor, and AI agents not just as coding assistants, but to automate business workflows, clarify requirements faster, and reduce development time significantly. My strength is knowing where AI creates real productivity gains and where traditional engineering is still the right call. With 20+ years in software development and experience serving clients across Japan, the US, the EU, Australia, and Asia Pacific, I understand how to work across different business cultures, communication styles, and project expectations. ✅ CORE EXPERTISE: ・Mobile: Flutter, FlutterFlow, React Native ・AI / LLM: OpenAI API, Claude, Dify, RAG, LangChain, n8n ・Backend: Ruby on Rails, Node.js, Python ・Cloud: Firebase, Supabase, AWS, Google Cloud ・Low-code: FlutterFlow, Bubble, Kintone ✅ DOMAIN EXPERTISE: ・Mobile Apps & Cross-platform Development ・AI-powered Applications & Workflow Automation ・SaaS & MVP Development ・Booking & Reservation Systems ・E-commerce & Marketplace ・Healthcare & Wellness Apps ・Real Estate & Property Management ・HRTech & Job Matching

Help startups and indie hackers build secure, reliable, and scalable software, allowing founders to focus on business growth without worrying about technical limitations or system failures. Some of my past projects: - Invygo: a car subscription platform operating in the UAE and Saudi Arabia, serving over 20,000 long-term paying subscribers (from 1 yr), more than 100,000 total subscribers, and managing over 5,000 vehicles. - Ayyeka: a global IoT platform for critical data management, processing more than 3 million data points per hour across the US, Europe, MENA, and Asia. How can I help: - Design or improve scalable and reliable software architectures. - Do improvements for security and compliance requirements. - Build production-ready MVPs. - Build reliable and measurable AI solutions using LLMs, RAG, and agents. Also much experience for fixing hallucinations in AI systems. - Lead cross-functional teams and technical projects to achieve business goals. - Mentor junior engineers. I offer a free 15-minute consultation. Feel free to schedule a call to discuss your product or technical challenges. Keywords: - Backend: Node, Python, NestJS, Hono, Go, GraphQL, REST, tRPC, WebSocket, SSE, WebRTC, etc - Frontend: React, Next, Angular, Vue, TypeScript, Tailwind. - Mobile: React Native, Expo, iOS, Android, BLE. - Data: PostgreSQL, MongoDB, Redis, Supabase, Prisma, Drizzle. - Cloud: AWS, GCP, Cloudflare, Docker, Kubernetes, Terraform, CI/CD. - AI: Generative AI, Agentic AI, Automation, RAG, LangGraph / LangChain, Mastra, Vercel AI SDK, Composio, Embeddings, Vector DBs. - Payments: Stripe, PayPal, RevenueCat, Paddle, Polar, Checkout.