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Blockchain engineer, 5 years writing Solidity in production. I've shipped smart contract systems across DeFi, NFTs and L1 consensus, and I build the frontend and backend around them too, so you're not stitching three freelancers together. Systems I've built and shipped: • Consensus and staking contracts for an L1, audited by a top-tier firm and live on mainnet through a token generation event. Validator committee logic, delegation, reward accounting, plus the foundation vesting schedules around it. • A community rewards platform with sybil resistance, pluggable quest types, and verification across X, Discord, Telegram and on-chain activity. Processed rewards for 95k+ contributors. • Token launch infrastructure with custom Uniswap V4 liquidity curves, where each launch spins up its own on-chain economy. • Gasless wallet UX using embedded wallets, EIP-7702 delegation and ERC-7579 smart accounts. Users tap once and never see a gas prompt or a seed phrase. • Cross-chain swap integrations across Base, Solana and BNB from a single interface, routed through aggregators. • DAO treasury and governance contracts, plus ERC-6551 token-bound account identity and dynamic metadata NFTs. • NFT platforms: upgradeable proxies, Beacon Proxy factories for user-generated collections, Merkle whitelisting, reveal mechanics, marketplace contracts with the backend behind them. On the AI side I build agent systems that actually run something, not demos. Most recent one is a Claude Code workspace running a marketing agency's daily operations: review replies on Google Business Profile and TripAdvisor, monthly Metricool reports delivered over Gmail, automated newsletters. Orchestrated through MCP servers with Playwright as the fallback for platforms with no write API, packaged so non-technical staff install it in one command. I hold an MSc in Machine Learning and AWS ML Specialty certification, so the AI work isn't a recent pivot. What I can take off your plate: • Smart contract development and refactors: Solidity, Foundry, Hardhat, proxy patterns, ERC-20/721/1155/4626 • Pre-audit hardening: Slither, fuzz testing, invariant tests, fixing what auditors flagged • DeFi and protocol integrations: Uniswap V3/V4, 0x, Relay, vesting and staking • Full-stack dApps: Next.js, React, TypeScript, wagmi/viem, Node.js, Go, PostgreSQL, Docker • Account abstraction and wallet UX for users who don't want to know they're using crypto • AI agents and MCP tooling wired into real systems and APIs

I'm a freelance Blockchain specialist with over 9 years of experience delivering high-quality decentralized applications, smart contract systems, and Web3 infrastructure. I've worked with a wide variety of clients. From DAOs and startups to established tech companies building: 🧠 Smart contracts (Solana, Solidity, Hardhat,...) 🧮 DeFi platforms (staking, liquidity mining, fee management, Native DEX,...) 🖼️ NFT marketplaces (minting, royalties, IPFS/Pinata, metadata management) 🌉 Cross-chain tools and integrations (Safe, Aave, Uniswap, Metamask, THORChain, CosmosSDK, IOTA,...) 🧰 Custom tooling and dApp frontends (React, Node.js, TypeScript, Ethers.js, Wagmi, Go,...) I'm also experienced in project leadership and backend systems, which helps me collaborate with full-stack teams, manage timelines, and deliver reliable software even under tight deadlines. ✅ Strong communication ✅ Web3-native mindset ✅ Adaptable to remote teams and async workflows If you’re looking for a committed and hands-on blockchain expert to bring your Web3 product to life, or scale it. Let’s connect.

Experienced blockchain developer with strong background in smart contract development, blockchain architecture and backend. Proven ability to implement and test decentralized applications on Ethereum and Hyperledger platforms.

❗️𝗚𝗲𝘁 𝗮 𝗙𝗥𝗘𝗘 𝟒𝟎-𝗺𝗶𝗻𝘂𝘁𝗲 𝗕𝗹𝗼𝗰𝗸𝗰𝗵𝗮𝗶𝗻 𝗖𝗼𝗻𝘀𝘂𝗹𝘁𝗮𝘁𝗶𝗼𝗻❗️ I’m a senior blockchain engineer focused on building and scaling production-grade Web3 systems, from smart contracts to full DeFi architectures and backend integrations. I collaborate with security auditors (including Certik) on selected projects when formal audit stage is required, but my main focus is clean architecture, secure contract design, and long-term maintainability before audit even becomes necessary. 🏆 Blockchain Expertise 11+ years building Web3 infrastructure, including: Smart contract development (Solidity, Rust, Move) Tokenomics & stablecoin architecture DeFi protocols: staking, liquidity pools, AMMs, lending/borrowing Wallet & blockchain integration Cross-chain bridges & interoperability Security audits, gas optimization, and threat analysis Node setup, backend APIs, indexing & on-chain data pipelines 𝗛𝗶𝗴𝗵𝗹𝗶𝗴𝗵𝘁𝗲𝗱 𝗣𝗿𝗼𝗷𝗲𝗰𝘁𝘀: Gold-backed Stablecoin System (Liechtenstein Launch) ✔ KYC onboarding, Sumsub integration ✔ Smart contracts on Ethereum + Polygon ✔ Oracle pricing + OTC gold price feeds ✔ Token mint/burn mechanics ✔ Reserve-backed auditing model ✔ Whitelist & transfer-restriction compliance ✔ Storage-fee mechanism (token balance decay) ✔ Full on-chain/off-chain architecture DeFi Protocols (AMMs, staking, farming) ✔ Smart-contract suite (Solidity) ✔ Reward distribution mechanisms ✔ Price oracle integration (Chainlink) ✔ Security hardening & audit fixes NFT platforms & minting engines ✔ ERC-721 / 1155 collections ✔ Royalty logic, metadata generation ✔ Claiming contracts, allowlists, randomness 𝗕𝗹𝗼𝗰𝗸𝗰𝗵𝗮𝗶𝗻 𝗧𝗲𝗰𝗵 𝗦𝘁𝗮𝗰𝗸: Smart Contracts: Solidity, Rust (Solana), Move (Aptos/Sui) Frameworks: Hardhat, Foundry, Truffle, Anchor Security: Slither, Mythril, Echidna, Certora On-Chain Data: TheGraph, SubQuery, custom indexers Blockchains: Ethereum, Polygon, BNB Chain, Arbitrum, Optimism, Avalanche, Solana, TON Backend: Node.js, NestJS, PostgreSQL, Redis, Docker Tools: Chainlink, Safe (Gnosis), IPFS, Pinata, Fireblocks Want a secure, scalable blockchain product, not a risky MVP? Send the documentation, and let’s build it correctly from day one. 𝗞𝗲𝘆𝘄𝗼𝗿𝗱𝘀: Blockchain, Web3, Blockchain Developer, Web3 Developer, Smart Contract Developer, Solidity Developer, Rust Developer, Move Developer, Ethereum Developer, DeFi Developer, Smart Contract Audit, Security Audit, Tokenomics, Stablecoin Development, NFT Development, ERC20, ERC721, ERC1155, Solidity Engineer, Blockchain Architecture, DApp Backend, Oracle Integration, Chainlink, Hardhat, Foundry, Web3 Security, Multi-Chain Deployment, DeFi Protocol, Yield Farming, Staking Contract, Vesting Contract, Governance Token, On-Chain Data, TheGraph, EVM Developer, Crypto Developer, Blockchain Consultant, Token Development, ICO/IDO Smart Contracts, Bridge Development, Layer 2 Developer, Polygon, Arbitrum, Optimism.

𝗜 𝗵𝗲𝗹𝗽 𝗰𝗼𝗺𝗽𝗮𝗻𝗶𝗲𝘀 & 𝗲𝗻𝘁𝗿𝗲𝗽𝗿𝗲𝗻𝗲𝘂𝗿𝘀 𝗯𝘂𝗶𝗹𝗱 𝘁𝗵𝗲 𝗯𝗲𝘀𝘁 𝗪𝗲𝗯𝟯 𝗽𝗿𝗼𝗷𝗲𝗰𝘁𝘀 𝗮𝗻𝗱 𝗕𝗹𝗼𝗰𝗸𝗰𝗵𝗮𝗶𝗻 𝗯𝗿𝗮𝗻𝗱𝘀 📈 𝘁𝗵𝗿𝗼𝘂𝗴𝗵 𝗦𝗖𝗔𝗟𝗔𝗕𝗟𝗘 𝗱𝗲𝘃𝗲𝗹𝗼𝗽𝗺𝗲𝗻𝘁 𝗮𝗻𝗱 𝗦𝗧𝗥𝗔𝗧𝗘𝗚𝗜𝗖 𝗰𝗼𝗻𝘀𝘂𝗹𝘁𝗶𝗻𝗴 🔥 +175 projects, +20M in revenue, +3M in funds raised 𝗔𝗹𝗹 𝗼𝗳 𝘁𝗵𝗲𝗺 𝘁𝗮𝗸𝗲𝗻 𝘁𝗵𝗿𝗼𝘂𝗴𝗵 𝗺𝘆 𝗔-𝗭 𝗽𝗿𝗼𝗰𝗲𝘀𝘀 𝘁𝗼 𝗰𝗿𝗲𝗮𝘁𝗲 𝘁𝗵𝗲 𝗯𝗲𝘀𝘁 𝘁𝗲𝗰𝗵𝗻𝗼𝗹𝗼𝗴𝘆 𝗮𝗻𝗱 𝗶𝗻𝗳𝗿𝗮𝘀𝘁𝗿𝘂𝗰𝘁𝘂𝗿𝗲 𝗲𝗻𝘀𝘂𝗿𝗶𝗻𝗴 𝘀𝗲𝗰𝘂𝗿𝗶𝘁𝘆 & 𝗲𝗳𝗳𝗶𝗰𝗶𝗲𝗻𝗰𝘆. 🎯 "𝙉𝙤 𝙦𝙪𝙚𝙨𝙩𝙞𝙤𝙣𝙨 𝙖𝙨𝙠𝙚𝙙, 𝙩𝙝𝙞𝙨 𝙜𝙪𝙮 𝙞𝙨 𝙩𝙝𝙚 𝙗𝙚𝙨𝙩 𝙤𝙛 𝙩𝙝𝙚 𝙗𝙚𝙨𝙩. 𝙄 𝙝𝙖𝙫𝙚 𝙙𝙤𝙣𝙚 𝙖 𝙫𝙚𝙧𝙮 𝙩𝙝𝙤𝙧𝙤𝙪𝙜𝙝 𝙧𝙚𝙨𝙚𝙖𝙧𝙘𝙝 (𝙛𝙤𝙧 𝙬𝙚𝙚𝙠𝙨!) 𝙩𝙤 𝙛𝙞𝙣𝙙 𝙖 𝙧𝙚𝙖𝙡𝙡𝙮 𝙜𝙤𝙤𝙙 𝙗𝙡𝙤𝙘𝙠𝙘𝙝𝙖𝙞𝙣 𝙙𝙚𝙫𝙚𝙡𝙤𝙥𝙥𝙚𝙧, 𝙖𝙣𝙙 𝙝𝙚 𝙚𝙭𝙘𝙚𝙚𝙙𝙚𝙙 𝙢𝙮 𝙚𝙭𝙥𝙚𝙘𝙩𝙖𝙩𝙞𝙤𝙣𝙨 1000%. 𝙉𝙤𝙩 𝙤𝙣𝙡𝙮 𝙝𝙚 𝙞𝙨 𝙫𝙚𝙧𝙮 𝙥𝙧𝙤𝙛𝙚𝙨𝙨𝙞𝙤𝙣𝙖𝙡 𝙖𝙣𝙙 𝙨𝙠𝙞𝙡𝙡𝙚𝙙 𝙬𝙝𝙚𝙣 𝙞𝙩 𝙘𝙤𝙢𝙚𝙨 𝙩𝙤 𝙘𝙪𝙨𝙩𝙤𝙢𝙞𝙯𝙚 𝙨𝙢𝙖𝙧𝙩 𝙘𝙤𝙣𝙩𝙧𝙖𝙘𝙩𝙨, 𝙢𝙞𝙣𝙩𝙞𝙣𝙜 𝙬𝙚𝙗𝙨𝙞𝙩𝙚𝙨, 𝙗𝙪𝙡𝙠 𝙪𝙥𝙡𝙤𝙖𝙙𝙨 𝙩𝙤 𝙤𝙥𝙚𝙣𝙨𝙚𝙖, 𝙨𝙚𝙩𝙩𝙞𝙣𝙜 𝙨𝙚𝙧𝙫𝙚𝙧𝙨 𝙚𝙩𝙘, 𝙗𝙪𝙩 𝙝𝙚 𝙞𝙨 𝙖𝙡𝙨𝙤 𝙫𝙚𝙧𝙮 𝙣𝙞𝙘𝙚, 𝙥𝙖𝙩𝙞𝙚𝙣𝙩, 𝙖𝙣𝙙 𝙝𝙚𝙡𝙥𝙨/𝙛𝙞𝙭𝙚𝙨/𝙖𝙙𝙟𝙪𝙨𝙩𝙨 𝙙𝙪𝙧𝙞𝙣𝙜 𝙩𝙝𝙚 𝙬𝙝𝙤𝙡𝙚 𝙥𝙧𝙤𝙘𝙚𝙨𝙨. 𝙄 𝙝𝙞𝙧𝙚𝙙 𝙖 𝙙𝙤𝙯𝙚𝙣 𝙥𝙚𝙤𝙥𝙡𝙚 𝙛𝙤𝙧 𝙢𝙮 𝙉𝙁𝙏 𝙥𝙧𝙤𝙛𝙚𝙘𝙩, 𝙖𝙣𝙙 𝙩𝙝𝙞𝙨 𝙬𝙖𝙨 𝙗𝙮 𝙛𝙖𝙧 𝙢𝙮 𝙜𝙧𝙚𝙖𝙩𝙚𝙨𝙩 𝙚𝙭𝙥𝙚𝙧𝙞𝙚𝙣𝙘𝙚. 𝙏𝙝𝙖𝙣𝙠𝙨 𝙖 𝙡𝙤𝙩 𝘼𝙣𝙞𝙤𝙡 😀" ⭐️⭐️⭐️⭐️⭐️ 🗣 Tom Olssen - Vengeaful Beasts 🗣 𝗟𝗶𝗸𝗲 𝘄𝗵𝗮𝘁 𝘆𝗼𝘂’𝗿𝗲 𝗵𝗲𝗮𝗿𝗶𝗻𝗴? 𝗜𝗻𝘃𝗶𝘁𝗲 𝗺𝗲 𝘁𝗼 𝘆𝗼𝘂𝗿 𝗷𝗼𝗯 𝗼𝗻 𝗨𝗽𝘄𝗼𝗿𝗸 𝘁𝗼 𝘀𝗰𝗵𝗲𝗱𝘂𝗹𝗲 𝗮 𝗙𝗥𝗘𝗘 𝗱𝗶𝘀𝗰𝗼𝘃𝗲𝗿𝘆 𝗰𝗮𝗹𝗹 𝘁𝗼 𝗳𝗶𝗻𝗱 𝗼𝘂𝘁 𝗶𝗳 𝘄𝗲 𝗰𝗮𝗻 𝗯𝘂𝗶𝗹𝗱 𝘀𝗼𝗺𝗲𝘁𝗵𝗶𝗻𝗴 𝗮𝗺𝗮𝘇𝗶𝗻𝗴 𝘁𝗼𝗴𝗲𝘁𝗵𝗲𝗿. 🔎 𝗛𝗲𝗿𝗲’𝘀 𝘄𝗵𝗮𝘁 𝘀𝗲𝘁𝘀 𝗺𝗲 𝗮𝗽𝗮𝗿𝘁 𝗳𝗿𝗼𝗺 𝗮𝗻𝘆𝗼𝗻𝗲 𝗲𝗹𝘀𝗲 𝘆𝗼𝘂 𝗰𝗼𝘂𝗹𝗱 𝗵𝗶𝗿𝗲 𝘁𝗼 𝗵𝗲𝗹𝗽 𝘆𝗼𝘂: 🔸 I deliver exceptional results from the start. Many clients reach out to me after trying less experienced talent or in-house solutions that didn’t meet their expectations. By choosing me, you’re securing a product that will make you proud and run smoothly for years to come. 🔸 You’re never reliant on me to stay in control! My development approach emphasizes clear, ongoing communication and transparency. I ensure that you have full ownership and understanding of everything built. 🔸 Working closely with Blockchain companies has allowed me to establish exclusive partnerships with some of the most prominent names in the Web3 industry. From Marketing, PR, Go-to-Market Strategy, and Tokenomics to NFT Strategy, Legal Structure Setup, VC Fundraising, and KOL, I offer comprehensive expertise. 🔸 Security is never compromised. Too many times in the Web3 world we see projects getting shattered - funds stolen, servers crashing, trust from users lost. That’s why I include thorough quality assurance testing at every stage, with final checks before your product is delivered. 𝗜𝗻𝘃𝗶𝘁𝗲 𝗺𝗲 𝘁𝗼 𝘆𝗼𝘂𝗿 𝗷𝗼𝗯 𝗼𝗻 𝗨𝗽𝘄𝗼𝗿𝗸 𝘁𝗼 𝘀𝗰𝗵𝗲𝗱𝘂𝗹𝗲 𝗮 𝗙𝗥𝗘𝗘 𝗱𝗶𝘀𝗰𝗼𝘃𝗲𝗿𝘆 𝗰𝗮𝗹𝗹 𝘁𝗼 𝗳𝗶𝗻𝗱 𝗼𝘂𝘁 𝗶𝗳 𝘄𝗲 𝗰𝗮𝗻 𝗯𝘂𝗶𝗹𝗱 𝘀𝗼𝗺𝗲𝘁𝗵𝗶𝗻𝗴 𝗮𝗺𝗮𝘇𝗶𝗻𝗴 𝘁𝗼𝗴𝗲𝘁𝗵𝗲𝗿. 🔎 𝗦𝗘𝗥𝗩𝗜𝗖𝗘𝗦 & 𝗦𝗢𝗟𝗨𝗧𝗜𝗢𝗡𝗦: ✅ Ethereum / Solana / BSC / Polygon (EVM) Customized Smart Contract Development ✅ Blockchain & Web3 Consultation (Smart Contract Ecosystem Design, Tokenomics, Whitepaper) ✅ EVM Smart Contract Audits (Automated Testing, Security Breach Search, Gas Efficiency, etc.) ✅ NFT Collection (ERC721 / ERC721A / ERC1155) creation (Whitelist, Shareholder Dividends, Burn mechanism, Reveal/Unreveal, Access Control, etc.) ✅ NFT Minting Dapps ✅ NFT Staking Contracts + Staking Dapps ✅ ERC20 Tokens (Basic Tokenomics, Staking Features, Buy Limits, Fees, etc.) + ICOs / IDOs ✅ DAOs ✅ NFT Marketplace ✅ Decentralized Exchange (Uniswap / Pancakeswap) ✅ Launchpad (Seedify) ✅ Yield Farming + DeFi Protocol ✅ Image & Metadata Generation Algorithm for NFT Artwork + IPFS Upload ✅ Solana NFT Smart Contract + Minting Dapp (Candymachine, Metaplex) ✅ 2D & 3D Graphic Design, Animations, and Promo Teaser Videos 𝗧𝗘𝗖𝗛 𝗦𝗧𝗔𝗖𝗞: ✅ Solidity, Hardhat / Truffle / Remix, Slither, Ethereum / Binance / Polygon / Avalanche / Optimism / Solana ✅ React.JS + Next.JS (Web3.JS, ethersJS), AngularJS, HTML, CSS & JavaScript (jquery, Bootstrap) ✅ Node.js, NestJS, ExpressJS, Docker, Python, Amazon AWS, MongoDB, MySQL ✅ Figma, AdobeXD, PSD ✅ Github / Gitlab / Bitbucket, Slack, Trello / Notion / Clickup / Jira 𝗜𝗻𝘃𝗶𝘁𝗲 𝗺𝗲 𝘁𝗼 𝘆𝗼𝘂𝗿 𝗷𝗼𝗯 𝗼𝗻 𝗨𝗽𝘄𝗼𝗿𝗸 𝘁𝗼 𝘀𝗰𝗵𝗲𝗱𝘂𝗹𝗲 𝗮 𝗙𝗥𝗘𝗘 𝗱𝗶𝘀𝗰𝗼𝘃𝗲𝗿𝘆 𝗰𝗮𝗹𝗹 𝘁𝗼 𝗳𝗶𝗻𝗱 𝗼𝘂𝘁 𝗶𝗳 𝘄𝗲 𝗰𝗮𝗻 𝗯𝘂𝗶𝗹𝗱 𝘀𝗼𝗺𝗲𝘁𝗵𝗶𝗻𝗴 𝗮𝗺𝗮𝘇𝗶𝗻𝗴 𝘁𝗼𝗴𝗲𝘁𝗵𝗲𝗿. 🔎

I’m a senior Shopify App Developer, MERN specialist, and full-stack developer with 10+ years of experience in Shopify, Shopify Plus, custom apps, public apps, private apps, API integrations, data migration, and complex eCommerce systems. As a Shopify App Developer, full-stack developer, web developer, react developer, python developer, wordpress developer, and blockchain developer, I build stores, apps, dashboards, and workflows that are fast, stable, scalable. 🚀 Full-Cycle Shopify, MERN, and App Development. As a Shopify App Developer and full-stack developer, I don’t just write code. I build eCommerce systems that support real business operations. Whether you need a Shopify app, Shopify Plus customization, Shopify data migration, admin tools, public app development, private app development, shopify speed improvement, dropshipping setup, automation, or technical support, I can help from planning to launch. My main focus is Shopify App Developer work, MERN development, full-stack developer solutions, and scalable systems for brands that need clean code, better UX, backend logic, and conversion. I also support web developer tasks, react developer work, python developer scripts, wordpress developer projects, blockchain developer features, mern stack apps, React interfaces, Node.js backends, MongoDB databases, and API integrations. 💻 Core Expertise - Shopify App Developer services for custom Shopify apps, public apps, private apps, and embedded apps - Shopify App Developer support for Shopify Plus workflows, checkout logic, admin tools, subscriptions, and B2B features - Shopify App Developer integrations with APIs, ERPs, CRMs, payments, fulfillment tools, and analytics platforms - MERN and mern stack development using MongoDB, Express.js, React, and Node.js - full-stack developer support for frontend, backend, databases, cloud services, and deployment - full stack developer architecture for dashboards, portals, SaaS tools, and internal systems - react developer work for storefronts, app interfaces, Polaris components, and interactive UI - React development with Redux, TypeScript, JavaScript, HTML, CSS, SCSS, and component logic - python developer support for data migration, scripts, automation, backend tools, and API workflows - wordpress developer support for WooCommerce, WordPress migration, plugin logic, and frontend fixes - web developer support using HTML, CSS, JavaScript, Liquid, PHP, Laravel, APIs, and cloud tools - blockchain developer support for wallet flows, Web3 integrations, NFT logic, and token-gated features ⭐ How I Can Help If you need a Shopify App Developer to build a custom app, I can plan the logic, design the architecture, develop the interface, connect APIs, test the workflow, and prepare the app for real use. If you need a MERN developer or mern stack expert, I can build web apps with React, Node.js, Express, and MongoDB. If you need a full-stack developer or full stack developer for an eCommerce platform, I can connect frontend, backend, database, and integrations into one stable system. I can also help as a react developer for clean interfaces, as a python developer for scripts and automation, as a wordpress developer for migration and WooCommerce support, as a web developer for theme and frontend work, and as a blockchain developer for Web3 features. My Shopify App Developer experience also covers app migration, debugging, webhooks, billing logic, product sync, order sync, customer sync, inventory sync, and dashboards. 🎯 My Approach Every project starts with understanding your store, business model, app logic, customer journey, data structure, and technical constraints. As a Shopify App Developer, MERN engineer, full-stack developer, full stack developer, react developer, python developer, wordpress developer, web developer, and blockchain developer, I focus on stable architecture, clean development, QA, and simple handoff. For Shopify projects, I check app logic, Shopify API limits, webhook flows, data migration risks, checkout behavior, speed issues, and conversion gaps. For MERN and mern stack projects, I focus on React structure, Node.js backend logic, MongoDB data design, API security, deployment, and scalability. For full-stack developer and full stack developer tasks, I make sure frontend, backend, database, and integrations work together without fragile shortcuts. Clients choose me because I combine Shopify App Developer experience, MERN execution, full-stack developer thinking, full stack developer flexibility, and real eCommerce understanding. If you need a reliable Shopify App Developer, MERN specialist, full-stack developer, full stack developer, mern stack engineer, react developer, React expert, python developer, wordpress developer, web developer, blockchain developer, Shopify data migration specialist, custom app builder, API integration expert, or eCommerce technical partner, lets discuss.