Anh Trần Sĩ Nguyên

Built a custom Android keyboard from scratch using InputMethodService and integrated Firebase AI for text rewriting and grammar correction. Deployed Gemma 3 Nano on-device, improving inference by ~60% versus cloud calls, and led a team of 5 engineers.

Built a transcription and summarization backend from scratch using self-hosted STT and multi-provider AI (Gemini/OpenAI), with thousands of active users. Implemented RAG with a vector database, replaced cloud speech APIs with an in-house STT pipeline, and led a 12-engineer team; mobile stack was Flutter with a Python/FastAPI backend and Firebase.

Architected a LangGraph multi-agent system where AI agents performed sentiment/technicals/backtesting and o3 produced final decisions without tool calling. Reduced API costs by self-hosting vLLM with GPT-OSS 120B and deployed a Django REST Framework backend on the SUI blockchain network for a team of 10 engineers.

Built a blockchain wallet app from the ground up supporting Ethereum, Polygon, BNB, and XENE plus decentralized storage. Implemented a blockchain crawler to index transactions and NFTs (thousands of events/day), delivered WebSocket updates in under a second with Redis pub/sub, and led 20 engineers on the mobile side.

Used Gemini Vision to extract ingredients from food photos and estimate calorie intake with ~85% accuracy. Implemented RAG with a vector database and LangChain for structured ingredient extraction, and delivered the full Django REST Framework backend with a 2-person team.

Developed a Flutter mobile app for smart camera accessories, including high-speed capture, time lapse, wireless flash control, and on-the-go file management. Implemented real-time data streaming via WebSocket using Provider and Clean Architecture with a team of 2.

Built a Kotlin mobile client for a blockchain strategy game with real-time gameplay mechanics and on-chain asset management. Worked with a team of 5 engineers and applied clean architecture patterns.

Built an Ethereum NFT gallery app enabling users to mint, browse, and trade digital art peer-to-peer. Implemented NFT minting and trading smart-contract integration using Kotlin with Jetpack Compose Desktop and MVVM under Clean Architecture.

Implemented 3D photo editing features in Swift using The Composable Architecture. Integrated RevenueCat for subscription management and delivered updates as part of a team of 2.

Built a mobile app and backend from scratch for an AI chat assistant integrated with the OpenAI API. Optimized prompts for quality and token efficiency and delivered the feature set with a team of 3 using Kotlin/Android Native and Python.

Developed AR features to help users discover nearby places of interest such as restaurants, ATMs, hospitals, and public transport. Built the app using C# Xamarin for Android/iOS with Clean Architecture and Firebase as part of a team of 15.

Profiled and optimized a crypto exchange mobile app covering trading, staking, and portfolio experiences. Implemented a Flutter app using RxDart and BLoC to handle live market data feeds with a team of 22 engineers.

Built and maintained a mobile networking app for belly dance professionals and fitness instructors. Implemented Kotlin Android features with RxJava/RxAndroid and Clean Architecture with a team of 8.

Built a virtual try-on feature where Unity renders 3D garments onto a user from a 2D photo to preview clothing before purchase. Developed the Kotlin Android app with Clean Architecture and MVVM, contributing to reduced return rates, with a team of 24 engineers.

Built a privacy-first secure data vault using end-to-end RSA encryption so users can store and share personal data with full privacy control. Developed the Kotlin Android app with Protobuf, AWS SDK, and Firebase as part of a 5-engineer team.

Earned a BE in Computer Science from Vietnam-Korea University of Information and Communication Technology.