Dan Napierski
Verified Expert in Engineering
Artificial Intelligence (AI) Developer
Boston, MA, United States
Toptal member since April 28, 2016
Dan is a seasoned software architect and technology consultant specializing in innovative solutions to complex challenges. With over two decades of experience, he applies rigorous testing and deep expertise in blockchain, AI, and ML to build resilient, "bulletproof" systems. His track record of delivering impactful results for clients, from ambitious startups to global corporations, makes him a valuable asset to any team seeking a technological edge.
Portfolio
Experience
- Artificial Intelligence (AI) - 20 years
- C# - 15 years
- APIs - 10 years
- Blockchain - 10 years
- Python - 10 years
- Machine Learning - 6 years
- Node.js - 3 years
- React - 2 years
Work Experience
President
Napierski Consulting
- Developed and deployed an autonomous trading robot operating across four major US cryptocurrency exchanges using Python and machine learning (ML).
- Led the development of several models using AWS SageMaker, Python, and Mathematica. Each accurately predicted home listing prices in a large metropolitan area using MLS listings in a supervised learning environment.
- Developed and deployed Solidity contracts on the Ethereum blockchain using Truffle and a custom Node.js and React front end. Executed RPC commands using Web3.js to publish and execute contracts on test and main networks.
- Architected the payment and collateral system on the Stellar blockchain. Developed a fork of the Stellar core in C++ to support custom ledger features.
- Created a chatbot using IBM’s Watson that processed legal contracts to determine effective dates and critical clauses contained within.
- Administered full Ethereum, BTC, and LTC nodes in a local development environment and virtual infrastructure using Ansible, Terraform, and Docker.
- Created an alt-coin, forked from Litecoin, capable of storing and querying text records on the blockchain.
- Audited a complex Node.js, React, and Redux web application to identify security concerns and performance issues. Recommended steps to automate deployments in Azure and manage pull requests in Git.
Full-stack Product Engineer
SimplyWise, Inc.
- Architected and built a Python FastAPI application enabling subject matter experts to evaluate LLM and prompt performance on product matching tasks against a corporate product API. Automated app deployments on DigitalOcean from a GitHub repository.
- Designed and implemented a Node.js (Express) call handling service integrated with Twilio, providing real-time WebSocket-based phone interactions, user session management, database persistence, and operational telemetry for call events.
- Developed an asynchronous Python service supporting SMS reminders and persistence for the phone system, implementing background processing, database workflows, and Twilio messaging integration using FastAPI and PostgreSQL.
AI Auditor
The Higher Education Assistance Group, Inc
- Audited the AI agent’s codebase and browser performance, identifying UI errors and console bugs. By analyzing system logs and debugging edge cases, I ensured the agent was stable and production-ready for launch.
- Optimized the build scripts and deployment pipelines across Netlify and Boxpress. By resolving configuration issues and build failures, I created a reliable CI/CD workflow that guaranteed seamless site delivery.
- Partnered with developers to resolve all technical audits to client satisfaction. I translated complex error reports into rapid fixes, ensuring the final product exceeded performance and quality standards.
Lead Research Engineer
University of Southern California
- Led the DARPA-funded development of a robust machine learning pipeline for text and image processing, leveraging TensorFlow, PyTorch, Hugging Face, Docker, and Kubernetes for scalable deployment on AWS.
- Authored Dockerfiles to generate specialized Conda and Pip environments, providing researchers access to the GAIA project's advanced machine learning (ML) frameworks and pre-trained models (including LLMs like BERT).
- Co-authored the award-winning paper, “GAIA: A Fine-grained Multimedia Knowledge Extraction System,” recognized as Best Demo Paper at the Association for Computational Linguistics.
- Managed virtual infrastructure deployment and image publishing for complex ML components, including natural language processing, semantic reasoning, and computer vision.
- Collaborated extensively with researchers on pipeline component integration, testing, and documentation, ensuring system robustness and research integrity.
- Trained and mentored HPC administrators on the provisioning and maintenance of hundreds of advanced GPU-accelerated nodes and the latest libraries for cutting-edge ML research.
- Resolved complex software and hardware issues, including critical cybersecurity vulnerabilities, collaborating with researchers and institute stakeholders.
Co-founder and CTO
Versara Trade
- Co-founded and led the technology strategy for a fintech startup, designing and implementing an innovative blockchain-based lending system enabling cryptocurrency-backed loans.
- Developed and deployed production-grade Solidity smart contracts (including ERC-20 and ERC-721 standards) on Ethereum, utilizing Truffle, Ethers.js, and Web3.js.
- Engineered a custom Node.js and React front end, complete with automated UI testing for a robust user experience.
- Represented the company at industry events and collaborated with executive leadership on strategic product development and roadmap planning.
President
Phfeast, Inc.
- Founded Phfeast, Inc., as a software company engaged with social issues. Developed a loyalty program that provided free restaurant meals to families in need.
- Created a suite of secure, high-performance, RESTful web services in .NET, responsible for fully supporting both a popular AngularJS web app and mobile app prototype.
- Developed an automated email alert subscription service and profile management system, regularly sending thousands of custom messages per day.
- Performed a web application performance audit and analysis that led to significant page load time improvements.
- Implemented automated functional tests, load tests, and executive reports, employing .NET tools, SQL Server Reporting Services, and Lua web API scripts.
- Integrated Google Maps, AWS, OAuth providers, and social media plugins within a responsive web offering.
- Implemented SEO pre-rendering techniques to support proper indexation of AngularJS pages by internet search engines.
Director of Software Engineering
PolyRemedy, Inc.
- Delivered a complete Android smartphone app, a RESTful web service API, and a dynamic HTML5 user interface within 12 months.
- Produced a 1st-in-class web service platform for in-home patient assessments and therapeutic fulfillment by healthcare professionals that protected HIPAA data.
- Drove the transformation of an existing engineering group into a high-performing team by implementing Agile methods, code reviews, and automated testing.
- Managed the engineering department budget, staffing, and multiple product schedules throughout the development lifecycle.
- Collaborated closely with heads of marketing, clinical research, and operations to coordinate product deliveries.
- Analyzed camera sensor data from multiple smartphone models.
- Incorporated event-driven text messaging into our mobile app.
Software Engineering Team Lead
PolyRemedy, Inc.
- Led a distributed team of engineers, designers, and quality assurance professionals in releasing an innovative software product for home health aides and visiting nurses.
- Turned diverse user needs and stakeholder desires into achievable milestones, resulting in on-time and well-tested product delivery.
- Managed web application availability and medical product fulfillment operations.
- Served as software architect, DevOps manager, and security chief.
- Produced a scalable SQL Server database design and Entity Framework mapping for efficient querying and retrieval by .NET web services and automated services.
Principal Software Engineer
Unidesk Corporation
- Integrated LDAP user accounts, VMware vSphere and View resources, and external APIs to create a broad set of secure .NET web services to manage virtual machines and application deployment.
- Integrated ActiveMQ messaging and inter-process communication using .NET remoting for a scalable, distributed architecture.
- Redesigned critical business applications to improve performance, reliability, and maintainability.
- Served as scrum master to a cross-functional team of six developers working on a range of product features.
- Automated testing and deployment in both Microsoft .NET IIS and Linux Apache Mono environments using Python, NUnit, NCover, and Bamboo.
Founder and Chief Architect
Napierski Consulting
- Directed software development within a client team during the development of a large-scale data-driven web application offering custom financial reports.
- Redesigned a client data model using SQL Server and NHibernate to facilitate efficient database querying.
- Advised large and medium-sized clients in the adoption of Agile development methods.
- Completed evaluations of internet technologies for clients to improve website performance, security, and usability.
- Developed custom software testing tools for Mathematica.
Senior Software Engineer
Arts Alliance Labs, Inc.
- Developed a recommendation server for a large DVD rental company based on collaborative filtering technology.
- Designed and implemented the membership and administration systems for multiple websites in a widespread European digital cinema initiative.
- Drove the adoption of a number of best practices, including test-driven development.
- Set up a continuous integration server to automate builds and deployments.
- Created a tiered architecture for a high-performance web application.
Software Engineer | Scientist
Charles River Analytics, Inc.
- Redesigned an advanced human behavior representation (HBR) based upon the recognition-primed decision (RPD) model for a government research project.
- Developed a component-based architecture that allowed users to construct a wide variety of autonomous intelligent agents.
- Organized communication between the development team and the government sponsor.
- Co-authored and presented a research paper on the project at the Conference on Behavior Representation in Modeling and Simulation.
- Implemented Bayesian network, fuzzy logic, and expert system technologies integrated within a Department of Defense simulation.
Project History
GAIA: A Fine-grained Multimedia Knowledge Extraction System
Education
Master of Science Degree in Computer Science
Harvard University - Cambridge, MA, USA
Bachelor of Science Degree in Economics
Duke University - Durham, NC, USA
Certifications
Fintech: Future Commerce
MIT
Skills
Libraries/APIs
API Development, REST APIs, Web3.js, Node.js, Google API, Amazon API, Google Maps, D3.js, Entity Framework, React, Twilio API, jQuery, Facebook API, PyTorch, Kraken, Coinbase API, Scikit-learn, NumPy, Pandas, OpenAI API, TensorFlow, Web3.py
Tools
GitHub, Jira, Terraform, Mathematica, Microsoft Visual Studio, Ninject, Xcode, Git, Microsoft Team Foundation Server, Atom, VMware vSphere, Stellar SDK, Eclipse IDE, MATLAB, AWS Command Line Interface (CLI), Microsoft Excel, ChatGPT, GIS, Grafana, Named-entity Recognition (NER), Multiple Listing Services (MLS)
Languages
Python, C#, PHP, Solidity, Java, Swift, C++, SQL, JavaScript, XML, HTML, Haskell, Lua, GraphQL, TypeScript, HTML5
Frameworks
.NET, Flutter, NUnit, NHibernate, Entity, ASP.NET, ASP.NET MVC 5, ASP.NET Web API, ASP.NET MVC, AngularJS, Bootstrap, Angular, Flask, Tailwind CSS, Botpress.io, Next.js, JSON Web Tokens (JWT), React Native
Paradigms
Agile Software Development, Continuous Integration (CI), DevOps, Agile Project Management, Cross-platform, Concurrent Programming, Object-oriented Design (OOD), Test-driven Development (TDD), Design Patterns, Agile, HIPAA Compliance, REST, Mobile Development, High-performance Computing (HPC), ETL, Microservices, Back-end Architecture, Change Management
Platforms
Blockchain, Windows, Ethereum, iOS, Android, Azure, Mobile, Linux, Docker, Kubernetes, NVIDIA CUDA, Amazon Web Services (AWS), AWS Lambda, Decentralized Exchanges (DEXs), Netlify, Twilio, Zendesk, Google Cloud Platform (GCP)
Storage
Microsoft SQL Server, Azure SQL, MySQL, Amazon S3 (AWS S3), MongoDB, PostgreSQL, Databases, Redis
Industry Expertise
Banking & Finance, Trading Systems
Other
Bitcoind, Fintech, Cryptocurrency, Machine Learning, RESTful Web Services, Artificial Intelligence (AI), Web App Development, Mobile App Development, API Design, DApps, Software Development, ÐApp, Blockchain Development, Front-end Development, eCommerce, Agentic AI, Data Science, Large Language Models (LLMs), Large Language Model Operations (LLMOps), Architecture, SDKs, APIs, Code Review, Product Owner, System Architecture, Cloud, Blockchain & Cryptocurrency, Smart Contracts, Decentralized Finance (DeFi), ERC-20, Ethereum Virtual Machine (EVM), Ethereum Smart Contracts, IBM Watson Analytics, Mobile Wallet, Bitcoin, SSL Certificates, Cryptography, Agile Software Testing, Video Streaming, Computer Graphics, Natural Language Processing (NLP), Computer Vision, Location Services, Network Programming, Optimization, Virtualization, Bayesian Statistics, Generative Pre-trained Transformers (GPT), CTO, Trading, Trading Bots, Algorithmic Trading, Systematic Trading, OAuth, Web Services, LDAP, Litecoin, Distributed Software, Cloud Computing, CI/CD Pipelines, Software Architecture, Data Modeling, Full-stack, Cybersecurity Automation, Leadership, Mentorship, Finance, Economics, Statistics, Chemistry, Mathematics, Encryption, AI Agents, Software, AI Research, Social Networks, Deep Learning, Object Detection, Lending, LangChain, SEO Marketing, Prompt Engineering, AI Chatbots, Document Processing, Crypto, Full-stack Development, Web Development, Chatbots, Cloud Infrastructure, Integration, Healthcare IT, Software Design, API Integration, Machine Learning Operations (MLOps), Recommendation Systems, Retrieval-augmented Generation (RAG), Cryptocurrency Exchanges, Gemini API, FastAPI, IT Security, Exchanges, Data Engineering, Geographic Information Systems, Fuzzy Logic, Bayesian Networks, Simulations, 3D Simulations, Expert Systems, Infrastructure, RESTFul APIs, Back-end, Quality Assurance (QA), Audit Testing, Bug Fixes, Edge Functions, SaaS, Supabase, Vite, GitHub Actions, Technical Leadership, Prometheus, Minimum Viable Product (MVP), GPU Computing, AI Integration, OpenAI, ChatGPT API, ChatGPT Prompts, Startups, Auditing, Higher Education, Regulated Industries, HIPAA Electronic Data Interchange (EDI), Orchestration, Workflow, Generative Artificial Intelligence (GenAI), Fractional CTO, IT Strategy, Technical Project Management, Software Development Lifecycle (SDLC), Business Strategy, WebSockets, Authentication, Deployment, AI Consulting, AI Systems, Cloud Architecture, Data Privacy, Microsoft 365, RAG Architecture, Data, Technical Writing, Project Review, Milestone Tracking, Image Processing, Solution Architecture, 2D Image Processing, Data Processing, Technical Design, ML Pipelines, BERT, RAG Systems, AI Programming, AI Design, Communication, Team Productivity, Software as a Service (SaaS), Low Code, Scalable Platforms, AI Model Training, Training, Audits, Risk Management, Scalability, Security, Mobile Apps, SMS, Healthcare Software, Development, Sales, Customer Experience, Back-end Development, RAG Pipelines, Vibe Coding, Chatbot Conversation Design, Business Continuity & Disaster Recovery (BCDR), Cloud Platforms, Commercial Real Estate, ETL Pipelines, Property Valuation, Third-party APIs, Web Scraping, OpenAI SDK, Data Anonymization, Optical Character Recognition (OCR)
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