I have Expert-Vetted Talent (EVT) badge - it's Upwork's top 1% freelancers — pre-screened by Upwork Talent Managers and experts in their field. Out of ~30 million programmers worldwide, only a few thousand know Algorithms & Data Structures better than I do, which is proven by programming competitions. Please, contact me if you need that skill level (top 0.01%). I can do algorithmic/performance work in C/C++, Python, SQL, Java, MQL4, MQL5, C#, Assembly, JavaScript, Julia, Rust, and probably other languages - learning them rapidly. I also work with AI, mostly in NLP and NLU: large language models including OpenAI GPT-3, Bloom, BloomZ, GPT-J 6B, LLaMA, Alpaca, etc.; HuggingFace Transformers, Accelerate; Petals, Deepspeed, zfp/zfpy; CUDA, CPU, and MPS (AArch 64 M2 MacOS Metal GPU) backends. I have some work experience with Apple Neural Engine (ANE). In AI, I also worked with XGBoost for predictions (including trading), LibSVM, TensorFlow, PyTorch, Scikit-learn, etc. I have the hardware in my home office for training and inference with large language models and other AI. English: C1 (Grammarly plugin says I use more unique words than 95% of other users, native speakers included). Polish: B1 (86%). Russian, Belarusian: Native. - With unique skills in Algorithms & Data Structures, I improve programs asymptotically (often 100 or more times on large input data). - 29 years of programming (started Basic and assembler on ZX Spectrum), 24 years of C/C++, 16 years of commercial work experience + 3 years of research projects. - Contributed to widely used Open Source projects: LLVM/Clang (my contribution is XRay profiler on ARM32 and AArch64 systems), Katana Graph (multiple small contributions mostly driven by the proprietary part where I do GPU/CUDA), CBMC "C Bounds Model Checking" (I contributed parallelized output of DIMACS formatted Boolean Satisfiability formula), oatpp (C++ web framework, I contributed bug-fixes), OWL (OptiX Wrapper Library, I contributed build fixes for Ubuntu), Galois (research project for distributed computations on graphs, I contributed GPU improvements) - Actively participated in bug reporting and reproduction (for NVIDIA CUDA, Cadical&kissat boolean satisfiability solver, JBOSS, MariaDB, Tensorflow, Linux, etc) - Led several open-source projects of my own: ProbQA (a video game recommendation system based on a high-performance Bayesian inference engine with CUDA, SIMD, and multi-threading); InSoAr (automatic reconstruction of software architecture from source code ), a multi-threaded Boolean Satisfiability solver, etc. Working for hire, implemented: - efficient multi-threading, scaling real-world workloads almost linearly with the number of CPU cores (128x for AMD Ryzen Threadripper 3990X) - SIMD vectorization (SSE/AVX), up to 8x improvement in computing thread or even copying (see my "Faster alternatives to memcpy" answer on Stackoverflow, URL upon request). - cache-aware algorithms: up to 50x improvement on some workloads - up to 20 trillion operations/second in CUDA (thousands of times faster than CPU) - up to the theoretical limit (6.8 Gigarays/second on RTX 2080 laptop GPU) in ray-tracing with OWL and OptiX - AVX512 and RTM (Restricted Transactional Memory) based acceleration, 16x improvement for float numbers -up to 20x improvements to cryptocurrency miners on CPU using AVX512 and cache-friendly algorithms - crypto-miners for Ethereum, Bittensor, Qubic 15K reputation on Stackoverflow: (1915854/serge-rogatch) Topcoder SRM score: 1480 - among top 5K programmers in the world - top 0.02% (rSerge) I developed all kinds of networking applications, from Linux Kernel modules up to Web applications. The majority of work was, of course, done at TCP/IP level with socket calls like send/recv/select. Programming languages: C++, C++11/14/17/20, C, Python, x86/x64/ARM/AArch64 assembly, SQL, C# .NET, JavaScript, HTML, CSS, Java, MQL4, MQL5, XML, Cypher, Rust. Libraries/Frameworks: PyTorch, Tensorflow, HuggingFace Transformers/Accelerate/Safetensors, Hivemind/Petals, OpenAI, tiktoken, Django, Flask, STL, LibSVM, XGBoost, libcurl, Selenium, PyTorch, Transformers. Technologies: OpenMP, CUDA, SIMD (AVX&SSE, RTM), Linux Kernel Modules, OptiX/OWL, RTX, raytracing. Theory/Principles/Know-how/Methodologies: Algorithms & Data Structures, Performance Optimization, Artificial Intelligence, Multithreading, Vectorization, OOP, Low-latency, High-frequency, Blockchain. Open source code: Clang, LLVM, LLVM's compiler-rt library, Linux Kernel, a few of my own repositories, contributions to AI and Algorithm open-source projects such as Petals and CBMC. Tools/APIs/Architectures/Platforms: PostgreSQL, MSSQL, MySQL, Neo4j, MATLAB, CMake, GIT, MT4, MetaTrader 5, Conda, PyCharm. Virtual Machines / Containers: Docker, VMWare, VirtualBox, QEmu, Hyper-V. OSes: Windows, Linux, Android, macOS

96.8% retrieval accuracy. 150-page contracts processed in under 60 seconds. Zero cross-tenant data leakage. I build RAG and AI systems that survive real production, not just demos, and clients keep hiring me back to build the next one. I'm Top Rated Plus, with 3+ years building AI systems and 7+ years in full-stack engineering. A lot of my work is repeat business. One client has brought me back 5+ times, because the systems hold up after launch, when real users and messy data arrive. RAG and document intelligence are my deep end, but I build complete production systems end to end: SaaS platforms, automations, and full-stack MVPs. The same discipline that keeps a RAG system reliable keeps the simpler builds clean, which is why teams trust me with both. RECENT WORK DocsFlow | Document Intelligence Platform 96.8% retrieval accuracy Hybrid search with source-linked, citation-backed answers 150-page documents processed in under 60 seconds, down from 3 to 5 minutes Four-layer tenant isolation with zero cross-tenant data leakage Around 85% AI cost reduction through model routing and caching SureCiteAI / LPA Analyzer | Legal & Contract Intelligence RAG across thousands of documents with grounded, citation-validated outputs Deterministic validation layer so financial figures are never generated by the LLM Built for legal and compliance-sensitive workflows LeadFlow AI | Multi-Agent Operations Platform AI-powered qualification, routing, and follow-up Integrated across Supabase, WhatsApp, APIs, and n8n Reduced manual operational effort by 40 to 70% (Also: multi-agent game-dev systems and real-time computer vision for fitness. Happy to share.) WHY TEAMS HIRE ME A cheaper freelancer can usually get an MVP working. The problems show up later, when real users, messy data, scaling, edge cases, security, and AI cost all arrive at once. That is exactly when architecture starts to matter, and when getting it wrong gets expensive. I'm more senior and product-minded than a typical freelancer, but more hands-on and cost-effective than an agency or an early senior hire. In practice: fewer wrong turns, faster decisions, and a system built right from day one. TECHNOLOGIES Next.js, TypeScript, Python, PostgreSQL, Supabase, Pinecone, pgvector, OpenAI, Claude, Gemini, Llama, LangGraph, CrewAI, Stripe, Vercel, AWS. Microsoft, Google, and IBM AI certified. SPEAKING TechStars Startup Week, DeFi Summit London, LevelUP KL Tell me what you're building and the outcome you need. If it has to actually work in production, that's where I'm strongest.

I provide precise Web Scraping, contact list building, email list building, LinkedIn list building, Data Research, Data Mining, market research, Email Marketing, Klaviyo Email Marketing, Cold Email, Email Design, Mailchimp email marketing, email newsletter, email deliverability, and email campaign services. With over 7 years of experience, I deliver both high-quality lead lists and targeted email sequences that drive engagement and conversions. Lead Generation ✦Web Scraping for targeted data extraction ✦Contact list building, email list building & prospect list building ✦LinkedIn list building via Sales Navigator ✦Data Research, Data Mining & market research ✦Email Scraping & verification (100% bounce-checked) ✦Deliverables: company details, contact names, job titles, verified emails, phone numbers, LinkedIn URLs, industry, location, and any custom filters Tools: LinkedIn, Sales Navigator, ZoomInfo, Apollo, Lusha, Neverbounce, Million Verifier, custom scraper scripts Email Marketing ✦Email Marketing strategy and setup (including Klaviyo email marketing & Mailchimp email marketing) ✦Cold Email outreach and automated drip sequences ✦Email Design and email newsletter creation ✦Email Campaign management and scheduling ✦Email deliverability monitoring and optimization Tools: Mailchimp, Klaviyo, Outreachbin, Smartlead AI, Brevoo, Instantly AI 📌Send your project details and criteria, and I’ll prepare a tailored lead list and email campaign that fits your timeline and goals.

I am a Senior Software Engineer with over 7 years of experience specializing in full-stack development and blockchain/Web3 technologies. I excel at designing and building scalable decentralized finance platforms, smart contracts, and high-performance backend APIs across multiple EVM-compatible chains. My expertise in Node.js, TypeScript, Solidity, and GraphQL allows me to lead complex technical projects from architecture through to deployment. I have successfully developed solutions that enhance user experience and deliver value in the fintech landscape. If you're looking to innovate and create impactful blockchain or software solutions, I am ready to collaborate and bring your vision to reality. Let's connect and discuss your project needs.

In my career as a software engineer, I have had the opportunity to work on a wide range of projects, from small scale to large, and in various industries. I have a strong foundation in computer science principles and am constantly looking for ways to improve my skills and stay up to date with the latest technologies. I am a detail-oriented and organized individual, and I pride myself on my ability to deliver high-quality code and meet project deadlines. Whether working on a complex blockchain/AI project or a simple automation script, I am always up for a challenge and enjoy the opportunity to use my creativity and problem-solving skills to find solutions. I believe that my combination of technical expertise and strong work ethic make me an ideal candidate for any software development project. 🟥Machine Learning: I have research published in the field of machine learning, and am proficient in using various tools and libraries such as Tensorflow and Keras. I have experience working with chat GPT and its fine-tuning API and have used it to develop code for parsing chat for a different use case. I am confident in my ability to tackle any ML project, including those involving chat GPT. 🟩Blockchain Development: I have extensive experience in blockchain development, focusing on NFT projects and games integrated with Unity. I have worked on backend and web3/contract development for these projects. 🟦Python Scripting: I am highly proficient in Python and have used it to create thousands of scripts for a variety of purposes, including Discord bots and automation tools. I have also professionally deployed Python scripts for more than 500k users worldwide. 🟨Full Stack Engineering: I have worked on a wide range of full-stack development projects, using a variety of tools and languages including C++, Python, Javascript, Go, PHP, Docker, Grafana, Kafka, Prometheus, Jenkins, Java, OCI, Springboot, AWS, React, React Native, Selenium, Tensorflow, Keras, Open CV, and Arduino. 🟧Programming Tutoring: In addition to my software engineering experience, I have also served as a coach and advisor for a significant educational tech company, where I advised students and stakeholders on course syllabi and work plans. I have also taught competitive programming and programming courses in college.

With 14+ years in software engineering, systems architecture, and IT leadership, I help founders, startups, and matured companies to turn complex ideas into clear, strategic, and actionable software solutions. Whether you're validating an early-stage concept, optimizing a legacy system, or building scalable infrastructure from scratch. I bring a unique blend of technical depth, strategic thinking, and team leadership. I’ve worked across most of the roles in IT like: software engineer, full-stack dev, project manager, QA, DevOps, team lead, and architect. This gives me a 360° view of the software development lifecycle, allowing me to make pragmatic, value-driven choices that move projects forward efficiently. If you're navigating technical uncertainty, scaling fast, or planning your next product, I'm here to guide you with clarity, confidence, and execution. The first step into the unknown is always easier with an expert by your side. Message me today. I’m here to help you build smart, scalable, successful systems :-).

[Sept 2024 - November 2025] Will respond slower as I am trying to clear out existing pipeline of work. Also, building stealth projects. If you would like to collaborate urgently, please reach out to me at henrybyhee@gmail.com! Currently building allocatool.app 🏅 Top Rated Plus on Upwork 🏅 High Project completion rate 🏅 AWS Solution Architect Certified since 2019 🏅 6+ years experience writing production grade code Worked with 20+ clients ranging from Startups to Enterprise teams across various timezones such as US, Germany, India and Australia. ✅ Proficient in Rust, Typescript, Java and Python ✅ Worked extensively with AWS cloud (EKS, Lambda, RDS, HA setup) ✅ Written multiple Solana on chain programs, cosmwasm and Solidity contracts ✅ Developed various bots interacting with brokers such IBKR, TD Ameritrade and Binance api How can I help you? ⭕ Build proof-of-concept or MVP bots in Rust (Eg: trading bots, NFT mint bots) ⭕ Create a low latency web application in Rust with actix-web. ⭕ Desktop application with tauri-rs ⭕ Package your code in Docker container efficiently ⭕ Create and deploy smart contract (Solana, cosm-wasm chains) ⭕ Write a custom pallet for your Substrate blockchain ⭕ Design Highly Available system on AWS Cloud ⭕ Deploy new Kubernetes Cluster on cloud ⭕ Migrate from Python/Typescript to Rust ⭕ Perform code reviews ⭕ Take previously stalled codebase over finish line My Process is typically as follows: 1. Gather requirements for an idea or product 2. Trim down unnecessary or non-urgent wants 3. Come up with features to satisfy each use case 4. Break up every feature into bite size task 5. Provide rough estimate for each task 6. Deploy to test environment (or testnet for smart contracts) for beta testing 7. Initiate a call for demo and ask for further improvement 8. Repeat from Step 1 if there are further requests Regardless of the size or complexity, I welcome discussing your project or idea and help you find success!

Companies usually hire me as an AI Consultant, AI Strategy & Innovation Partner for advisory and consultations for Business Process Automation. As a Chief Product Owner, I help turn ideas into products, hire the right people, and build delivery teams. Or as a Fractional CTO, I define architecture, select technologies, and lead engineering execution. Typical projects include AI agents, multi-agent orchestration systems, SaaS platforms, conversational AI with memory, AI companions, digital clones, sales agents, marketplaces, and AI-native web and mobile applications. Core Expertise • AI Agents & Workflow Automation (agentic systems, copilots, business automation) • Business Process Automation (ERP, CRM, HubSpot, Microsoft 365, OpenAI) • Conversational AI (voice, memory, digital personas) • AI Products (strategy, architecture, execution) • SaaS Platforms (operations, workflows, internal tools) • Marketplaces (creator economies, monetization systems) • AI Infrastructure (real-time systems, orchestration layers) • Web3 Systems (payments, tokens, utility design) Recent Products AI Digital Clone Platform - Callable A platform for creating AI-powered digital replicas of experts, founders, educators, influencers, and professionals. The system enables users to interact with AI clones through text and voice while preserving knowledge, communication style, and personality traits. Real-Time Robotics Brain Infrastructure - IronHeart.AI Conversational infrastructure for humanoid robots, kiosks, physical AI systems, and embedded devices operating in real-world environments. Low-latency conversation, interruption handling, contextual memory, multilingual communication, and edge deployment. AI Agent Marketplace for Wellness Industry [NDA] The platform combines conversational AI, voice interaction, appointment workflows, knowledge management, and subscription-based monetization. Agent-Based Data Intelligence Platform (NDA) Enterprise AI intelligence platform that allows organizations to interact with structured and unstructured data through AI agents. The system combines agent orchestration, MCP integrations, retrieval pipelines, workflow automation, and decision-support interfaces. AI Companion Platform - Amora Real-time AI companion ecosystem featuring voice conversations, persistent memory, emotional engagement systems, creator monetization, and AI-generated personalities. The platform enables creators to launch AI personalities for ongoing relationships with AI companions. AI Call Center Infrastructure & Sales Voice Agents [NDA] Conversational AI infrastructure for automated customer interactions, sales operations, inbound support, and call center automation. The system includes transcription, routing, analytics, conversation optimization, and multilingual voice interactions. AI-Powered Design Workspace & Proposal Automation B2B platform (VC Gallery) The platform combines project management, proposal generation, pricing automation, catalog management, financial tracking, and AI-assisted workflows into a unified workspace for managing complex design projects. Web3 AI Marketplace & Consumer Engagement Ecosystem - MAX44 AI & Beenachi Marketplace Web3-powered consumer platform combining AI agents, behavioral engagement systems, tokenized rewards, location-based interactions, and marketplace mechanics. The platform explores new models for user acquisition, consumer incentives, and AI-driven engagement. IoT Visualization & Industrial SCADA Platform – HyperVision The system provides operators, engineers, and plant managers with a centralized interface for monitoring production lines, industrial equipment, sensors, and operational processes across manufacturing facilities.

Innovative Solutions, Delivered Fast! As a Senior Full-Stack Developer with over 11 years of experience, I specialize in creating robust and scalable web applications. My expertise lies in AI LLMs, Node.js, React, Ruby on Rails, Blockchain, Solana Ecosystem, Web3 platforms, along with a variety of API integrations and SaaS systems. I'm passionate about delivering top-notch solutions that align with your business goals. What I Bring to the Table: ✅ Python expert with 8+ years of experience in TensorFlow, PyTorch, Django, Flask, FastAPI ✅ Expert in LLMs, Custom Chatbots, Jupyter Notebooks, Google Colab, NumPy, Pandas Generative AI ✅ Ruby on Rails Expert: Over 11 years of experience building reliable data-driven platforms. ✅ Responsive Frontend Development: Utilizing React, Next.js, Tailwind CSS, and Bootstrap to create fast, seamless user interfaces. ✅API & Backend Mastery: Crafting solid backend APIs with Node.js and integrating with Stripe, Firebase, Supabase, Twilio, and REST/GraphQL APIs. ✅Web3 Capabilities: Specialized in blockchain and smart contract interactions using Solidity, ethers.js, and Web3.js. ✅Custom Solutions: Developing tailor-made admin panels, dashboards, and internal tools that fit your business needs. ✅Cloud Deployment: Expertise in deploying production-ready applications on platforms like Vercel, AWS, and DigitalOcean. My Approach: I am committed to writing clean, maintainable code and focusing on scalability and documentation. With a product-focused mindset, I ensure that each project not only meets but exceeds expectations. Let’s turn your ideas into reality quickly and efficiently. Reach out today to discuss how I can contribute to your success!

I build native iOS and Android applications that work in the real world, in the field, offline, in complex physical environments where most mobile solutions fall apart. My focus is on technically demanding work: augmented reality and spatial computing, LiDAR-based 3D reconstruction and site scanning, RoomPlan-based room and space capture, GIS and GNSS field data collection, BLE and IoT device integration, and AI/ML features that actually ship. Not demos, production systems. I'm the founder of Quality Wolves, a senior-only engineering team. Everyone on the team has owned full project cycles and made architectural decisions. We take ownership of the technical scope, surface what matters, and keep things moving. You stay focused on your product, we handle the build. What I build: Native Mobile: Swift, SwiftUI, Kotlin, full-cycle iOS & Android development, App Store and Google Play delivery AR / Spatial Computing: ARKit, ARCore, RealityKit, RoomPlan, LiDAR scanning, point cloud processing, 3D reconstruction, Apple Vision Pro. GIS & Field Data: GNSS/RTK integration, offline-first architecture, geospatial data pipelines, custom map layers, QGIS compatibility AI & ML: LLM integration, computer vision, NLP, on-device inference with Core ML and TensorFlow Lite, OpenAI and custom model pipelines, TTS/STT Connectivity: BLE pairing flows, LoRa, IoT sensor integration, background sync, beacon tracking Our senior engineers use AI tools deliberately, not as a substitute for judgment, which means faster delivery without trading speed for technical debt. Good fit if you: Need someone who operates independently without hand-holding Are building something with real operational complexity Have been burned by teams that shipped demos and called it done Describe the problem you're trying to solve, send a message, and let's talk specifics.