John is available for hire
Hire JohnJohn McLaughlin
Verified Expert in Engineering
Blockchain Developer
New York, NY, United States
Toptal member since September 12, 2022
Bio
John is a back-end and platform engineer with 10+ years of experience architecting production systems, APIs, and data pipelines. He's built a multi-exchange platform in Python and FastAPI with third-party API integrations, live data processing, and an admin dashboard. He builds LLM systems focused on reliability, grounding outputs to their source and adding deterministic verification, so AI can't assert what it can't prove. John's depth extends to blockchain architecture across EVM and Solana.
Portfolio
McKurz Capital
Echidna, Games, Mythril, Code Review, Incident Response, Observability...
McKurz Capital
LLM Integration, Decentralized Finance (DeFi), Decentralized Applications...
McKurz Capital
CAD, Monte Carlo, Tokenomics, Code Review, Observability, Code Auditing...
Experience
- Web3 - 10 years
- Solidity - 9 years
- Docker - 9 years
- RESTFul APIs - 5 years
- Next.js - 5 years
- Amazon Web Services (AWS) - 5 years
- Solana - 4 years
- LLM Integration - 2 years
Preferred Environment
React, Next.js, Docker, Amazon Web Services (AWS), LLM Integration, Python, FastAPI, PostgreSQL, RESTFul APIs, TypeScript
The most amazing...
...thing I created is a document-extraction pipeline that pairs an LLM with deterministic verification, grounding values to their source and catching model misses.
Work Experience
Smart Contract Security Engineer
2024 - PRESENT
McKurz Capital
- Performed smart contract security assessments using Slither, Echidna, and Mythril, combining static analysis, property-based fuzzing, and manual review to find vulnerabilities and catch cases where contract logic violated its intended invariants.
- Conducted a full security assessment of a set of insurance smart contracts, documenting findings by severity with concrete remediation guidance.
- Led the security hardening of a production multi-exchange crypto trading platform, implementing Authelia two-factor authentication, JWT-based authentication, and nginx reverse-proxy hardening.
- Established platform-wide security operations, including secrets management, malware scanning, and fleet-wide CVE remediation across the deployment.
- Applied webhook signature verification, idempotency keys, and replay defense to components handling payments and settlement, where correctness directly protected real funds.
Technologies: Echidna, Games, Mythril, Code Review, Incident Response, Observability, Code Auditing, Startups
AI Integration Developer
2023 - PRESENT
McKurz Capital
- Integrated an LLM insight layer into Decent Portfolio, a peer-to-peer crypto portfolio tracker, using Claude models to generate portfolio analysis on top of a TypeScript, Helia, libp2p, and OrbitDB stack.
- Designed the integration to fit a decentralized, client-side architecture, handling API access and key security without exposing credentials in a public client.
- Used AI-assisted development daily, including Claude Code and the Model Context Protocol, to build and ship production features.
- Deployed and operated the application behind Cloudflare on self-managed infrastructure, keeping the AI features reliable in production.
Technologies: LLM Integration, Decentralized Finance (DeFi), Decentralized Applications, API Design, OrbitDB, Capacity Planning, Containerization, Code Review, Incident Response, Observability, Web Scraping, Code Auditing, Startups
Tokenomics Simulation Engineer
2022 - PRESENT
McKurz Capital
- Built cadCAD simulations to validate and stress-test tokenomics models, running Monte Carlo analysis across many demand scenarios to measure token value stability rather than relying on a single projected path.
- Modeled multiple stakeholder classes as distinct agents, including end users, infrastructure contributors, and DAO participants, to trace how value and capital flow across a token ecosystem.
- Used parameter sweeps to compare competing token designs head-to-head on value stability and downside risk, producing a clear basis for recommending one version over another.
- Diagnosed and corrected a Monte Carlo seeding fault that was silently collapsing runs to identical results, and separated genuine economic effects from compounding-noise modeling artifacts.
- Connected simulation findings to regulatory framing, including utility-versus-security considerations under the Howey framework, to support investor-ready and legally-relevant reporting.
Technologies: CAD, Monte Carlo, Tokenomics, Code Review, Observability, Code Auditing, Startups
Blockchain and Rust Developer
2026 - 2026
JoyPixels Inc
- Developed cross-platform desktop emoji picker using Tauri v2, Rust, and Vue with global keyboard shortcuts, system tray integration, and dual-window architecture for seamless emoji insertion.
- Eliminated external cliclick dependency by migrating to Tauri's native cursor_position() API, reducing installation complexity and improving reliability across macOS systems.
- Replaced clipboard-based emoji insertion with direct keystroke injection using macOS Core Graphics API, preserving user clipboard contents during emoji insertion.
- Implemented target app detection using AppleScript to capture display names instead of process names, ensuring accurate emoji delivery to VS Code, Sublime Text, and browsers.
- Built production macOS distribution packages (.app and .dmg), resolving Tauri version mismatches and documenting the build process for team handoff.
Technologies: Rust, Vue, JavaScript, TypeScript, MacOS, Tauri, AppleScript, AI Agents, Agentic AI, RESTFul APIs, Artificial Intelligence (AI), Claude Code, Large Language Models (LLMs), API Design, High Code Quality, Mapping, Systems Design, Compliance, Debugging, Site Reliability, Site Reliability Engineering (SRE), CI/CD Pipelines, Capacity Planning, Code Review, Incident Response, Observability, Code Auditing, eCommerce
Blockchain Solana and Rust Developer
2025 - 2025
JoyPixels Inc
- Designed and deployed multiple versions of a Solana NFT program using Rust, implementing core minting functionality and emoji-based domain logic.
- Built and integrated validation logic to ensure the uniqueness of emoji array combinations, preventing duplicate NFT minting on-chain.
- Created a front-end reservation system for NFT acquisition, providing streamlined user experience for token minting and emoji domain registration.
- Deployed program iterations to the Solana blockchain, handling on-chain asset storage and transaction processing.
Technologies: Rust, Solana, Blockchain, Smart Contracts, Ethereum, Web3, Vue, JavaScript, TypeScript, Ethers.js, User Interface (UI), User Experience (UX), Back-end, Architecture, Anchor, Blockchain Development, AI Agents, Agentic AI, RESTFul APIs, Artificial Intelligence (AI), Claude Code, API Design, High Code Quality, Debugging, Web Scraping, eCommerce
Blockchain Developer
2024 - 2025
All American Consultants LLC
- Architected and deployed a custom fungible token to the Solana mainnet, implementing tokenomics and establishing initial distribution infrastructure.
- Built full-stack liquid staking protocol with Rust smart contracts and React front end, enabling token holders to earn rewards through on-chain staking mechanisms.
- Created and deployed a sought-after NFT collection of 1,000+ unique digital assets, achieving strong secondary market trading volume and community adoption on Magic Eden marketplace.
- Developed proprietary marketplace program and web interface for project-specific NFT trading, implementing on-chain escrow and settlement logic.
- Integrated Discord authentication system with on-chain verification, restricting community access based on SPL token or NFT ownership.
- Executed social media campaign strategy to drive platform awareness, grow engaged user base, and facilitate organic community expansion across multiple channels.
- Designed and deployed an on-chain governance program enabling token-weighted voting on community proposals, establishing a decentralized decision-making framework.
Technologies: Blockchain, Cryptocurrency, Solana, Tokenomics, Crypto, Anchor, NFT Design, Non-fungible Tokens (NFT), Decentralized Finance (DeFi), Discord, Architecture, Stablecoins, Blockchain Development, AI Agents, Agentic AI, RESTFul APIs, Artificial Intelligence (AI), Claude Code, Docker, API Design, High Code Quality, Mentorship, Systems Design, System Administration, Legacy Software, Debugging, Site Reliability, Site Reliability Engineering (SRE), CI/CD Pipelines, Capacity Planning, Containerization, Code Review, Incident Response, Observability, Startups, eCommerce
Blockchain Developer
2024 - 2024
G.W. Pastrick Enterprises LLC
- Designed and developed an application to store encrypted academic records as on-chain NFTs where relevant stakeholders can retrieve these documents.
- Designed and developed a REST API where users can retrieve and decrypt user data by scanning a code.
- Designed a system where academic records can be uploaded in bulk and minted as NFTs through an NFT factory.
Technologies: Blockchain, Tokenization, Non-fungible Tokens (NFT), Smart Contracts, Ethereum Smart Contracts, Solidity, Blockchain Platforms, Ethereum, API Integration, User Interface (UI), User Experience (UX), Back-end, Uniswap, Architecture, Stablecoins, Blockchain Development, AI Agents, Agentic AI, RESTFul APIs, Artificial Intelligence (AI), Claude Code, API Design, High Code Quality, Data Modeling, Mapping, Mentorship, Systems Design, Compliance, System Administration, Debugging, Startups
Python Developer (via Toptal)
2024 - 2024
Lucas Flett
- Designed and developed a Python-based trading bot connector for decentralized and centralized cryptocurrency exchanges, optimizing execution speed and transaction efficiency.
- Created a custom Telegram UI that allowed users to start trading bot scripts, submit algorithm-based orders, and monitor execution status directly within the exchange account UI.
- Conducted detailed code reviews for team members by evaluating GitHub pull requests, ensuring code quality and alignment with project standards before repository updates.
- Researched and analyzed 3rd-party asset custody solutions to determine optimal integration strategies for enhanced platform security and compliance.
Technologies: Blockchain, Python, Decentralized Finance (DeFi), Solana, Solana.py, Rust, RPC, WebSockets, substream, Remix IDE, Telegram Bot API, Telegram Bots, API Integration, TradingView, Flask, Back-end, Uniswap, Architecture, AI Agents, Agentic AI, RESTFul APIs, Artificial Intelligence (AI), Claude Code, Auth, API Design, High Code Quality, AI Model Training, Observability, Automated Deployment Scripts, Startups
Full-stack Blockchain Developer
2023 - 2024
Mueller Health Foundation, Inc
- Developed minting of on-chain NFTs to represent documents stored on the TBConnect app related to tuberculosis research and analysis.
- Upgraded overall application from Node.js 8 to Node.js 16 and React 16 to React 17 in 2023. Upgraded dependencies and cleared all errors to improve overall performance.
- Deployed the upgraded back-end to an AWS EC2 instance, the front-end to an AWS S3 bucket, and various APIs to Amazon API Gateway. As a result, the application is now fast, scalable with resizable compute capacity, highly secure, and very efficient.
- Upgraded the chat and virtual meeting functionality from Twilio Video to the Zoom Video SDK to enable group meetings instead of one-to-one sessions.
- Updated the visual aesthetic of the front end to enhance the overall user experience, making it more intuitive, engaging, and visually appealing.
Technologies: Blockchain, Ethereum Smart Contracts, React, Node.js, Full-stack, JavaScript, Ethereum, Amazon Web Services (AWS), Twilio, Blockchain Design, Zoom, AWS Cloud Computing Services, Use Case Analysis, Ganache, Tokenization, RPC, WebSockets, Remix IDE, API Integration, User Interface (UI), User Experience (UX), Back-end, Architecture, Blockchain Development, AI Agents, MongoDB, RESTFul APIs, Artificial Intelligence (AI), PostgreSQL, Auth, MySQL, API Design, High Code Quality, Data Modeling, Mapping, Mentorship, Systems Design, Compliance, System Administration, Infrastructure, Legacy Software, Cloud Infrastructure, Debugging, Site Reliability, Site Reliability Engineering (SRE), CI/CD Pipelines, Containerization, Code Review, Incident Response, Observability, Observability Tools, Healthcare, Code Auditing
Web3 Back-end Developer
2023 - 2023
Polemarch LLC
- Developed an Ethereum NFT marketplace for listing Bitcoin ordinal inscriptions with full function to create, mint, and list EVM NFTs representing inscribed Bitcoin ordinals, BRC-20 tokens, and name inscriptions.
- Contributed to the smart contract Solidity smart contract behind the NFT marketplace featured createNFT, listNFT, cancelListing, addToCart, burn, and other relevant functions.
- Worked on the contract design that utilized OpenZeppelin audited contract library to ensure safety and security.
- Designed and developed a REST API for storing Bitcoin inscription off-chain data such as collection value, curation, real-time pricing of listed NFTs in terms of ETH/USD, etc. The API utilized MongoDB for storage.
Technologies: Blockchain, Web 3.0, Smart Contracts, Node.js, Python, Security, IT Security, APIs, Bitcoin, Ethereum, Data Queries, Databases, DevOps, Ethereum Virtual Machine (EVM), Software Architecture, DApps, Microservices Architecture, Cryptography, Computer Science, White Papers, Distributed Computing, Project Consultancy, Use Case Analysis, Binance Cryptocurrency Exchange, Tokenization, RPC, WebSockets, Remix IDE, API Integration, TradingView, Back-end, Uniswap, Architecture, Blockchain Development, RESTFul APIs, Artificial Intelligence (AI), MySQL, API Design, High Code Quality, Mapping, Debugging, Startups, eCommerce
Blockchain Developer
2023 - 2023
Levi Sirmons
- Developed an Ethereum wallet that removed and added specific functionalities to the basic Metamask web3 wallet.
- Added permissions to the web3 wallet where it can be used by team members who do not possess administrative rights and permissions to the firm's treasury wallet(s).
- Created a web3 wallet browser extension distribution that can be uploaded into Chrome, Firefox, or Brave.
- Assisted in designing a team workflow that allows for close supervision of trading strategies by platform administrators.
Technologies: JavaScript, Blockchain, MetaMask, Advisory, Strategy, Troubleshooting, TypeScript, Data Queries, Databases, Writing & Editing, Ethereum Virtual Machine (EVM), Software Architecture, Computer Science, Project Consultancy, Use Case Analysis, zkSync, Decentralized Finance (DeFi), Binance Cryptocurrency Exchange, RPC, WebSockets, Remix IDE, API Integration, TradingView, Back-end, Uniswap, Architecture, Blockchain Development, High Code Quality, Systems Design, Startups
Blockchain Developer
2022 - 2023
Currentz Corp.
- Worked as the lead blockchain developer for Currentz. Designed, developed, and deployed ER-C721 and ERC-1155 Solidity smart contracts for the Ethereum and EVM-compatible blockchains.
- Created a defined process for the team to set up NFT drops with a user interface for customers to mint and claim NFTs from their creative economy platform.
- Integrated not only Web 3.0 payments using cryptocurrencies through a Metamask wallet but also purchasing the NFTs using a credit card where customer knowledge of Web 3.0 is not necessary.
- Deployed contracts on Layer 2 chains such as Polygon or Optimism to allow the platform and its customers to save transaction "gas fees" when using cryptocurrencies.
Technologies: Solidity, JavaScript, Ethereum, Smart Contracts, Blockchain, React, MetaMask, Non-fungible Tokens (NFT), Blockchain & Cryptocurrency, Blockchain Platforms, Crypto, Security, IT Security, Technical Writing, Advisory, Blockchain as a Service, Strategy, Back-end Development, Web Development, Troubleshooting, TypeScript, Writing & Editing, Decentralized Autonomous Organizations (DAO), Ethereum Virtual Machine (EVM), Tokenomics, Software Architecture, DApps, Computer Science, Solana, Project Consultancy, Use Case Analysis, Ganache, Binance Cryptocurrency Exchange, Tokenization, RPC, WebSockets, Remix IDE, Vue, API Integration, User Interface (UI), User Experience (UX), Back-end, Architecture, Stablecoins, Blockchain Development, Docker, High Code Quality, Systems Design, Startups, eCommerce
Senior Blockchain Developer
2022 - 2022
John Nesgoda - Web3 Startup
- Developed an Ethereum Solidity smart contract with tokenomics functionalities.
- Implemented multi-signature wallet functionality as a method of custody.
- Added payment streaming functionality to multi-signature wallet orchestration.
- Designed and deployed a platform membership NFT token with an expiration date and the functionality to extend the expiration date.
Technologies: Blockchain & Cryptocurrency, Solidity, Decentralized Finance (DeFi), Ethereum Smart Contracts, Multisig, MetaMask, CTO, Electronic Payments, Fraud Prevention, Cryptocurrency Wallets, Payment APIs, Fintech, Branding, Cryptocurrency, Decentralized Systems, Web 3.0, Fintech Consultant, Foundry, Next.js, Ethers.js, GitHub, Node.js, Polygon, Crypto, Security, IT Security, JavaScript, Blockchain, Technical Writing, Advisory, Back-end Development, Web Development, Troubleshooting, TypeScript, Data Queries, Writing & Editing, Ethereum Virtual Machine (EVM), Tokenomics, Software Architecture, DApps, Computer Science, White Papers, Project Consultancy, Arbitrage, Use Case Analysis, Ganache, Tokenization, RPC, WebSockets, Remix IDE, Audits, TradingView, Back-end, Uniswap, Architecture, Stablecoins, Blockchain Development, High Code Quality, Code Review, Incident Response, Code Auditing, Startups
Lead Blockchain Developer
2017 - 2022
McKurz Capital Incorporated
- Founded McKurz as a part-time development shop for Web3 applications, submitting our apps to 11 ETHGlobal and two Chainlink hackathons. Several of these apps won prizes in hackathon competitions and the interest of venture capital firms.
- Built Ethereum smart contract web apps using development tools such as Truffle and Hardhat, with React and Next.js as front ends.
- Deployed an NFT factory/marketplace to the Polygon blockchain during the ETHGlobal DAOHacks hackathon.
- Developed a few storage apps deployed to the Filecoin blockchain that were submitted to hackathons last year, including Disco Rock Repo for the 1960s to 1990s disco, rock, and pop music and Fin File Crypto for crypto investment videos and documents.
Technologies: Solidity, Ethereum, Truffle, Hardhat, Node.js, React, Docker, Blockchain, Smart Contracts, Blockchain & Cryptocurrency, Decentralized Exchanges (DEXs), Full-stack, ERC-20, HTML5, CSS5, Web3.js, OpenSea, Bitcoin, CTO, Electronic Payments, Fraud Prevention, Cryptocurrency Wallets, Govtech, Payment APIs, Fintech, Branding, Cryptocurrency, Rust, Amazon Web Services (AWS), Decentralized Systems, Mobile Advertising, Web 3.0, Fintech Consultant, Hyperledger Fabric, Hyperledger, Kubernetes, Foundry, Netlify, Next.js, Ethers.js, GitHub, Polygon, Python, Cloud, Crypto, Cybersecurity, Twilio, Security, IT Security, MetaMask, JavaScript, DigitalOcean, Technical Writing, Advisory, Blockchain as a Service, Strategy, Back-end Development, Web Development, APIs, Troubleshooting, TypeScript, DevOps, Data Queries, Databases, PostgreSQL, Redis, Writing & Editing, Ethereum Virtual Machine (EVM), Tokenomics, Software Architecture, Technical Leadership, Leadership, DApps, Microservices Architecture, Cryptography, Computer Science, White Papers, Distributed Computing, GPU Computing, Solana, Azure, Project Consultancy, Twilio API, Arbitrage, Use Case Analysis, Arbitrum, zkSync, Ganache, Decentralized Finance (DeFi), Binance Cryptocurrency Exchange, Metaplex Sugar, Metaplex Candy Machine, RPC, WebSockets, Remix IDE, Vue, Telegram Bot API, Telegram Bots, API Integration, TradingView, Flask, User Interface (UI), User Experience (UX), Back-end, Uniswap, Architecture, Anchor, ICO, VRF, Blockchain Development, MongoDB, Agentic AI, RESTFul APIs, gRPC, Artificial Intelligence (AI), Claude Code, Cloudflare, AI Integration, API Design, High Code Quality, LLM Integration, Data Modeling, Mapping, Mentorship, Systems Design, Compliance, System Administration, Infrastructure, Legacy Software, Cloud Infrastructure, AI Model Training, Site Reliability, CI/CD Pipelines, Capacity Planning, Containerization, Code Review, Incident Response, Observability, Observability Tools, Automated Deployment Scripts, Web Scraping, Code Auditing, Startups, eCommerce
Adjunct Lecturer
2011 - 2022
CUNY-College of Staten Island
- Instructed on personal finance, using accounting software such as Microsoft Excel and QuickBooks.
- Led students on financial topics through a technology lens to better equip them for the 21st-century digital economy.
- Lectured on the history of blockchain, industry trends, and investing analysis into various projects such as Bitcoin, Ethereum, Solana, decentralized finance protocols, and NFTs.
Technologies: Windows, Google Drive, Excel 2010, Intuit QuickBooks, Bitcoin, Fraud Prevention, Cryptocurrency Wallets, Govtech, Fintech, Branding, Cryptocurrency, Decentralized Systems, Web 3.0, Crypto, Cybersecurity, Blockchain, Troubleshooting, Writing & Editing, Leadership, Project Consultancy, Data Modeling, Mentorship, Systems Design, Compliance
Teacher
2005 - 2022
New York City Department of Education
- Taught mathematics topics such as basic algebra, intermediate algebra and trigonometry, and logic and pre-calculus.
- Instructed entrepreneurship students about website development using HTML, CSS, and JavaScript.
- Expanded student knowledge to extend JavaScript development to Node.js, React, and Next.js, with additional topics toward server-based development.
- Introduced students to blockchain history and use cases, the theory on Ethereum smart contracts, and the potential of cryptocurrency-based applications.
Technologies: K-12 Education, Business, Mathematical Finance, Technical Writing, Personal Finance, Excel 2013, Excel 365, Intuit QuickBooks, JavaScript, HTML, CSS, Bitcoin, Cryptocurrency Wallets, Govtech, Branding, Node.js, Writing & Editing, Mentorship
Experience
Trustworthy LLM Document Extraction (Grounding and Arithmetic Verification)
https://document-extraction-coral.vercel.app/Document-extraction pipeline where you can click any extracted value to see exactly where it came from in the source, plus a math-verification layer that catches what the large language model (LLM) misses; measured at 0.98 micro-F1 on a labeled evaluation set: live demo and full pipeline (FastAPI, PostgreSQL, Next.js).
Peer-to-Peer Portfolio Tracker with AI Analyst
https://decent-portfolio.vercel.app/I built a peer-to-peer cryptocurrency portfolio tracker that stores data on a decentralized database using OrbitDB on IPFS instead of a centralized SQL store. The platform tracks multi-asset positions with live pricing, weighted-average cost basis, and real-time unrealized P&L, and includes an AI Analyst feature that generates natural-language analysis via Claude Sonnet 5 while keeping raw portfolio data inside OrbitDB.
The architecture separates a Next.js and TypeScript front end on Vercel from a self-hosted Helia, OrbitDB, and libp2p back end connected through a Cloudflare Tunnel. Infrastructure uses production-grade ingress without exposed ports or static IPs, managed through systemd for automatic recovery. The AI reasoning layer uses a context-bundle pattern that never exposes OrbitDB CIDs, identity material, or oplog entries, and the Anthropic SDK is isolated to a single file, so the model choice is swappable.
The project is a ground-up rebuild of a 2022 prototype, re-architected on OrbitDB v3 with document-level encryption.
Technologies: Next.js 16, React 19, TypeScript, Tailwind, OrbitDB v3, Helia, libp2p, Anthropic SDK, Claude Sonnet 5, Node.js, Cloudflare Tunnel, Vercel.
The architecture separates a Next.js and TypeScript front end on Vercel from a self-hosted Helia, OrbitDB, and libp2p back end connected through a Cloudflare Tunnel. Infrastructure uses production-grade ingress without exposed ports or static IPs, managed through systemd for automatic recovery. The AI reasoning layer uses a context-bundle pattern that never exposes OrbitDB CIDs, identity material, or oplog entries, and the Anthropic SDK is isolated to a single file, so the model choice is swappable.
The project is a ground-up rebuild of a 2022 prototype, re-architected on OrbitDB v3 with document-level encryption.
Technologies: Next.js 16, React 19, TypeScript, Tailwind, OrbitDB v3, Helia, libp2p, Anthropic SDK, Claude Sonnet 5, Node.js, Cloudflare Tunnel, Vercel.
Solana Liquidity Staking Pool App
https://mckurz-liquid-staking.vercel.app/OVERVIEW
This Solana DevNet liquid staking pool lets users stake SOL while maintaining liquidity via placeholder staking tokens. Users earn staking rewards, which can be claimed anytime. The app features an intuitive UI with deposit, withdrawal, reward claim functions, real-time pool, and user wallet stats.
FEATURES
• Stake and earn: Deposit SOL, receive liquidity tokens, and earn rewards.
• Claim rewards: Withdraw accumulated staking rewards anytime.
• Withdraw anytime: Unstake and reclaim original SOL.
• Live pool stats: Displays total deposits, rewards, and user balances.
• User-friendly UI: Simple deposit, withdrawal, and claim functions.
LIMITATIONS AND BEST PRACTICES
• Keep deposits small (approximately 0.50 SOL or less) for successful transactions.
TECH STACK
• Front end: Vite, React, Tailwind CSS
• Back end: Solana Web3.js, Anchor
• Smart contracts: Rust (Solana Program Library)
This project highlights my expertise in Solana smart contracts, decentralized finance apps, and Web3 front-end development with Vite for fast performance.
To connect to this application, you must have a Phantom or Solflare wallet funded with Solana Devnet tokens. You can visit https://faucet.solana.com/ to acquire SOL Devnet tokens.
This Solana DevNet liquid staking pool lets users stake SOL while maintaining liquidity via placeholder staking tokens. Users earn staking rewards, which can be claimed anytime. The app features an intuitive UI with deposit, withdrawal, reward claim functions, real-time pool, and user wallet stats.
FEATURES
• Stake and earn: Deposit SOL, receive liquidity tokens, and earn rewards.
• Claim rewards: Withdraw accumulated staking rewards anytime.
• Withdraw anytime: Unstake and reclaim original SOL.
• Live pool stats: Displays total deposits, rewards, and user balances.
• User-friendly UI: Simple deposit, withdrawal, and claim functions.
LIMITATIONS AND BEST PRACTICES
• Keep deposits small (approximately 0.50 SOL or less) for successful transactions.
TECH STACK
• Front end: Vite, React, Tailwind CSS
• Back end: Solana Web3.js, Anchor
• Smart contracts: Rust (Solana Program Library)
This project highlights my expertise in Solana smart contracts, decentralized finance apps, and Web3 front-end development with Vite for fast performance.
To connect to this application, you must have a Phantom or Solflare wallet funded with Solana Devnet tokens. You can visit https://faucet.solana.com/ to acquire SOL Devnet tokens.
EVM DeFi Staking Platform
https://mckurz-evm-staking-ui.vercel.app/PROJECT OVERVIEW
Developed a complete DeFi staking application on Base Sepolia that allows users to stake MckurzToken (MKT) and earn 17.16% APR. Built with React, Ethers.js, and Solidity smart contracts.
KEY ACHIEVEMENTS
• Engineered a precision-based reward system using Solidity with customizable APR settings.
• Built a responsive React UI with real-time staking metrics, MetaMask integration, and intuitive stake and unstake functionalities.
• Resolved critical precision issues in reward calculations to ensure accurate APR display and reward distribution.
• Fixed mathematical discrepancies between displayed rates and actual reward accumulation.
• Implemented proper TVL tracking and reward projections.
• Optimized contract interactions to minimize gas costs while maintaining accurate rewards.
• Verified contracts on BaseScan with proper documentation.
TECHNOLOGIES
Solidity, React, Ethers.js, OpenZeppelin, Foundry, Base (Ethereum L2)
The project demonstrates my expertise in DeFi platform development, addressing complex tokenomics challenges while delivering an intuitive user experience with reliable on-chain performance.
To use this application, you must connect a Metamask wallet and connect to the Base Sepolia network.
Developed a complete DeFi staking application on Base Sepolia that allows users to stake MckurzToken (MKT) and earn 17.16% APR. Built with React, Ethers.js, and Solidity smart contracts.
KEY ACHIEVEMENTS
• Engineered a precision-based reward system using Solidity with customizable APR settings.
• Built a responsive React UI with real-time staking metrics, MetaMask integration, and intuitive stake and unstake functionalities.
• Resolved critical precision issues in reward calculations to ensure accurate APR display and reward distribution.
• Fixed mathematical discrepancies between displayed rates and actual reward accumulation.
• Implemented proper TVL tracking and reward projections.
• Optimized contract interactions to minimize gas costs while maintaining accurate rewards.
• Verified contracts on BaseScan with proper documentation.
TECHNOLOGIES
Solidity, React, Ethers.js, OpenZeppelin, Foundry, Base (Ethereum L2)
The project demonstrates my expertise in DeFi platform development, addressing complex tokenomics challenges while delivering an intuitive user experience with reliable on-chain performance.
To use this application, you must connect a Metamask wallet and connect to the Base Sepolia network.
Solana DeFi Trading Bot - Automated Token Analysis and Trading System
Developed a sophisticated automated trading bot for the Solana blockchain that monitors and analyzes newly created tokens on pump.fun. The bot implements advanced price analysis algorithms with real-time monitoring of bonding curves, smart entry/exit strategies, and customizable trading parameters.
Key features:
• Real-time token detection and price analysis.
• Multi-factor trading decision system considering price movements, volume, and market momentum.
• Configurable risk management with price thresholds and volatility analysis.
• Automated buying and selling with slippage protection.
• Long-term holding mode for promising tokens.
• Comprehensive logging and transaction tracking.
• Robust error handling and retry mechanisms.
• WebSocket integration for real-time blockchain monitoring.
The bot is built using Python and integrates with Solana's blockchain infrastructure, demonstrating expertise in decentralized finance development, algorithmic trading, and blockchain technology.
Key features:
• Real-time token detection and price analysis.
• Multi-factor trading decision system considering price movements, volume, and market momentum.
• Configurable risk management with price thresholds and volatility analysis.
• Automated buying and selling with slippage protection.
• Long-term holding mode for promising tokens.
• Comprehensive logging and transaction tracking.
• Robust error handling and retry mechanisms.
• WebSocket integration for real-time blockchain monitoring.
The bot is built using Python and integrates with Solana's blockchain infrastructure, demonstrating expertise in decentralized finance development, algorithmic trading, and blockchain technology.
Solana NFT Marketplace
https://black-kitten-solana-nft.vercel.app/marketplaceSuccessfully developed and deployed a full-featured NFT marketplace on the Solana mainnet, combining robust blockchain functionality with an intuitive React-based user interface. The marketplace enables users to mint, buy, sell, and trade NFTs with minimal gas fees and fast transaction speeds.
Nature NFTs Marketplace
https://nature-nfts-marketplace-polygon.vercel.app/The Nature NFT Marketplace is an NFT factory deployed on the Polygon Mainnet blockchain. It allows users to create their own NFT from a digital image, list it for sale on the marketplace, and actively trade all users' NFT listings. It was built with an Ethereum smart contract that adds the previously mentioned functionality. I have deployed the app to the Polygon and Arbitrum blockchains in an effort to lower transaction "gas" fees. This project's GitHub repository can be found at Github.com/georgemac510/nature-nfts-marketplace-polygon.
Legal Documents Marketplace
The Legal Documents form repository is a datastore and marketplace for purchasing standard fillable-PDF legal documents such as a simple will, articles of incorporation for specific states or provinces, bill of sale samples, building contracts, and business plans. Currently, the legal documents are stored as .jpg files. In future iterations, the documents will be fileable-PDFs so users can fill them with unique information and use them for their purposes. The legal documents are stored on IPFS and deployed to the Goerli Ethereum Testnet as ERC-721 NFTs. This project's GitHub repository can be found at Github.com/georgemac510/blockchain-developer-bootcamp-final-project. Your Metamask account must be set to the Goerli blockchain to view and interact with the app.
Decentralized Token Exchange
https://mckurz-dex.vercel.app/The McKurz cryptocurrency exchange dApp was launched on the Ethereum Kovan Test Network in August 2020. It has since been upgraded to the Goerli testnet due to the Ethereum Merge and the deprecation of the Kovan chain. The exchange allows users to list buy and sell orders of different cryptocurrencies. The app is an older production and works best with unlocking Metamask with your password, refreshing the browser after connection, and possibly making a manual connection to the Metamask Goerli wallet (update shortly). If you need Goerli testnet tokens to test the app, please email john.mclaughlin@toptal.com with your Goerli Ethereum address, and testnet tokens will be sent to your address.
Safe Harbour Finance Reward Coin Staking App Deployed to zkSync
https://safeharbour-finance.vercel.app/The Safe Harbour Finance app allows users to stake native SAFE tokens and acquire rewards of the platform's native SAFE token. The app's uniqueness is that it is deployed to the zkSync testnet 2.0, where costs of staking, transfer, lending, or borrowing are quite inexpensive and secure. To use the app, you will need to add the 'zkSync alpha testnet' to Metamask. Directions for this process can be found at: https://v2-docs.zksync.io/dev/troubleshooting/important-links.html#testnet-network-info. Demonstrations of the app are available.
Education
2014 - 2016
Master's Degree in Education Administration
City University of New York (CUNY) - Hunter College - New York City, New York, United States
2005 - 2009
Master's Degree in Mathematics Education
City University of New York (CUNY)-Brooklyn College - New York City, New York, United States
1983 - 2005
Bachelor's Degree in Accounting, Business Management, and English
St. John's University - New York City, New York, United States
Certifications
JUNE 2024 - JUNE 2027
AWS Certified Developer – Associate
Amazon Web Services
JULY 2023 - PRESENT
AWS Partner: Accreditation (Technical)
Amazon Web Services Training and Certification
DECEMBER 2021 - PRESENT
ConsenSys Certified Ethereum Developer
ConsenSys Academy
SEPTEMBER 2020 - PRESENT
LFS171x: Introduction to Hyperledger Blockchain Technologies
The Linux Foundation | via edX
JUNE 2020 - PRESENT
The Python Mega Course: Build Ten Real World Apps
Udemy
SEPTEMBER 2019 - PRESENT
Modern React with Redux
Udemy
AUGUST 2019 - PRESENT
Codecademy Intensive Program: Build Front-end Web Apps from Scratch
Codecademy
FEBRUARY 2019 - PRESENT
Docker Mastery: The Complete Toolset From a Docker Captain
Udemy
Skills
Libraries/APIs
React, Node.js, Web3.js, Twilio API, Vue, Telegram Bot API, Auth, OpenZeppelin, Solana.py, React Redux, Libp2p, Pydantic
Tools
Microsoft Excel, MetaMask, Excel 2010, Git, GitHub, Ganache, Remix IDE, Claude Code, Docker Compose, Docker Swarm, Docker Hub, Zoom, Observability Tools, MATLAB, Excel 2013, CAD
Languages
Solidity, JavaScript, HTML, CSS, HTML5, Rust, Python, TypeScript, Python 3, Python 2, Markdown, AppleScript
Frameworks
Next.js, Truffle, Hardhat, Flask, Anchor, Redux, gRPC, Tauri
Paradigms
DevOps, Microservices Architecture, Distributed Computing, UI Design
Platforms
Docker, Linux, Ethereum, Hyperledger, Windows, Blockchain, Decentralized Exchanges (DEXs), Blockchain Platforms, Amazon Web Services (AWS), DigitalOcean, AWS Cloud Computing Services, Hyperledger Fabric, Netlify, Twilio, Azure, Vercel, Kubernetes, MacOS
Storage
MySQL, Databases, PostgreSQL, MongoDB, Redis, Docker Cloud
Industry Expertise
Binance Cryptocurrency Exchange, Healthcare, Cybersecurity
Other
Web3, Ethers.js, Distributed Team Management, Instruction & Coaching, Time Management, Infura, Non-fungible Tokens (NFT), Decentralized Finance (DeFi), Ethereum Smart Contracts, Ethereum Test Network, Google Drive, Technical Writing, Smart Contracts, Blockchain & Cryptocurrency, Full-stack, ERC-20, Multisig, Blockchain Design, Decentralized Autonomous Organizations (DAO), zkSync, OpenSea, Bitcoin, CTO, Electronic Payments, Fraud Prevention, Cryptocurrency Wallets, Payment APIs, Fintech, Branding, Cryptocurrency, Decentralized Systems, Web 3.0, Fintech Consultant, Foundry, Polygon, Cloud, Crypto, Security, IT Security, Advisory, Strategy, Back-end Development, Web Development, AWS Partner Network (APN), APIs, Troubleshooting, Data Queries, Writing & Editing, Pulse Width Modulation (PWM), Ethereum Virtual Machine (EVM), Tokenomics, Software Architecture, Technical Leadership, Leadership, DApps, Cryptography, Computer Science, White Papers, Solana, Project Consultancy, Arbitrage, Use Case Analysis, Metaplex Sugar, Metaplex Candy Machine, Tokenization, RPC, WebSockets, Audits, Telegram Bots, API Integration, User Interface (UI), User Experience (UX), Back-end, Uniswap, Architecture, Stablecoins, ICO, VRF, Blockchain Development, Cloudflare, AI Agents, Agentic AI, RESTFul APIs, Artificial Intelligence (AI), Large Language Models (LLMs), AI Integration, API Design, High Code Quality, LLM Integration, Data Modeling, Mapping, Mentorship, Systems Design, Compliance, System Administration, Infrastructure, Legacy Software, Cloud Infrastructure, AI Model Training, Debugging, Site Reliability, Site Reliability Engineering (SRE), CI/CD Pipelines, Capacity Planning, Containerization, Code Review, Incident Response, Observability, Automated Deployment Scripts, Web Scraping, Code Auditing, Startups, eCommerce, IPFS, CSS5, Arbitrum, Govtech, Mobile Advertising, Blockchain as a Service, GPU Computing, substream, TradingView, Filecoin, Intuit QuickBooks, K-12 Education, Business, Mathematical Finance, Personal Finance, Excel 365, HD Wallets, NFT Design, Token Design, Vite, Discord, OrbitDB, Helia, Prompt Engineering, FastAPI, Railway, Echidna, Games, Mythril, Monte Carlo, Decentralized Applications
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