Hi there, I'm Lionel J 👋

I'm a seasoned Embedded Systems and Application Development Engineer with over 15 years of experience in Linux and Android-based HAL, application, platform, and server development. From early Android porting (Cupcake era) to modern IoT and smart devices, I've specialized in Camera, Audio, SurfaceFlinger, and Multimedia HAL/Framework. Passionate about building innovative solutions for smart speakers, robots, and IoT ecosystems using C/C++, Python, Go, and Kotlin.

"The road is under your feet, the heart looks to the distance"

🚀 About Me

• 🔭 Currently working on: Camera video control systems and Public Address Systems at Hanwha Vision (using C++, Buildroot, GStreamer, and Pipewire).
• 🌱 Currently learning: I'm learning about Rust, WASM, and Stable Diffusion.
• 👯 Looking to collaborate on: Open-source IoT projects, Application Development Using Local LLMs
• 🤔 Looking for help with: Optimizing real-time audio processing in edge devices, Development of a Korean TTS Model that Runs Locally
• 💬 Ask me about: Delving into Android NDK internals, understanding the Android System, porting to embedded Linux, or building Linux applications.
• 📫 How to reach me: hybridego@gmail.com
• ⚡ Fun fact: I authored All About Android NDK (2012, Hanbit Media) – a go-to book for early Android developers!

🛠️ Skills

Languages & Frameworks

Development Environments & Tools

• Embedded: Buildroot, Yocto, Linux Device Drivers, Android HAL/NDK/SDK, ROS/ROS2, ESP32 Firmware
• Multimedia: FFmpeg, GStreamer, ALSA/TinyALSA, PulseAudio, Pipewire
• Databases: SQLite, MariaDB (MySQL), Neo4j
• IDEs & Tools: Vim, Android Studio, IntelliJ, VS Code, JIRA, Git
• Frontend/Other: QT, SDL, Vue3, Electron (Node.js)

Publications

• Publication: All About Android NDK (2012)

📈 Work Experience Highlights

Period	Company	Key Projects
May 2024 – Present	Hanwha Vision	Camera (C++, HW Codec) & Public Audio System (GStreamer, RTP, Multicast)
Sep 2023 – May 2024	Hyundai Autoever	Android Automotive OS-Navigation (Kotlin, AIDL, D-Bus)
Dec 2019 – Aug 2023	Kakao Enterprise	Kakao Home IoT Platform (Spring Boot, Kubernetes), Robot Tech (ROS2, SLAM), Smart Office (Nordic nRF52840, Matter), Kakao Mini Audio Enhancements
Oct 2014 – Nov 2019	Kakao	Kakao Mini Smart Speakers (Android BSP, Bluetooth Stack), IDC Sensors (ESP32, MQTT), Video Encoder Servers (FFmpeg, NVENC)
Jan 2013 – Sep 2014	Daum Communications	Bluetooth Beacon R&D, Indoor Air Quality Collectors, Song Recognition Receivers
Sep 2010 – Dec 2012	Insignal	Android NDK Training, Multimedia Engines, Navigation Apps

🎯 Featured Projects

• Kakao Home: Backend development of IoT Device Control system
• Kakao Mini Series: Full-stack development of Android-based smart speakers, including porting, HAL customizations, and audio tuning.
• Indoor Serving Robot: ROS2-based navigation and server integration with MQTT and KakaoTalk Chatbot.
• Smart Office Dashboard: BLE sensor networks with Django backend and Vue3 frontend for real-time monitoring.
• Home Appliance Control: Matter/Thread integration for voice-controlled appliances via smart speakers.
• Unmanned Store Verification: AI-driven camera and weight sensor system for product tracking.

Check out my repos for code samples: GitHub Repos

🌐 Connect With Me

Thanks for visiting! Let's build something awesome together 🚀

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