Marco Jardim
Verified Expert in Engineering
Blockchain Developer
Niterói - State of Rio de Janeiro, Brazil
Toptal member since March 16, 2022
Marco isn't just a blockchain expert; he's a digital visionary. With a master's in blockchain and digital currencies, Marco has pioneered transformative solutions like the Gov Token, a tool combating corruption in Brazilian state loans. His contributions to UNICEF's Giga aim to connect every school to the internet by 2030. Beyond the tech, his passion lies in reshaping our world through blockchain's potential. Dive deeper and discover how Marco revolutionizes the digital frontier.
Portfolio
Experience
Availability
Preferred Environment
Ethereum, Bitcoin, Solidity, Node.js, Lightning Network, DApps, Blockchain, Decentralized Finance (DeFi), Back-end, Hardhat
The most amazing...
...feat I've achieved is leveraging blockchain at UNICEF's Giga, connecting schools globally to the internet, empowering millions of children.
Work Experience
Web3 Security Engineer
Stealth Startup
- Leveraged the capabilities of GPT-4 for natural language analysis, which improved the tool's understanding of code documentation and potential areas of exploitation.
- Drove a 30% reduction in false positives through iterative refinement and feedback loops, optimizing the tool's performance and reliability.
- Integrated Mythril, Slither, and Echidna into the tool's pipeline, enhancing its accuracy in identifying critical vulnerabilities by 70%.
- Designed a cutting-edge fuzz testing mechanism that automatically generated over 10,000 test cases, uncovering 95 unique vulnerabilities in previously audited contracts.
- Conducted over 150 security audits on externally developed smart contracts, providing comprehensive feedback and recommendations that safeguarded over $500 million in digital assets.
- Spearheaded the incorporation of Mythril, leading to a 40% increase in detecting logical and computational flaws in smart contracts.
- Initiated and maintained a comprehensive vulnerability database, which now houses records of vulnerabilities and their solutions.
Blockchain Engineer
UNICEF's Giga
- Designed and coded web3 pages to enable secure and efficient tracking of donations and grants, reducing administrative costs.
- Conducted rigorous testing and auditing of smart contracts, ensuring zero security breaches and 100% compliance with industry standards.
- Collaborated with the Giga team and external partners to integrate blockchain technology into the initiative's broader strategy, increasing stakeholder engagement.
- Conducted research on emerging blockchain trends and technologies, presenting findings to the team and contributing to developing Giga's long-term roadmap.
- Trained and mentored junior blockchain developers, increasing team productivity and knowledge-sharing.
- Coordinated with external auditors to ensure accurate reporting of blockchain-related expenses and compliance with regulatory requirements.
MEV Bot Developer
Stealth Client
- Developed an automated Ethereum trading bot that executes front-running and back-running strategies based on real-time transaction analysis.
- Integrated multiple APIs, including Alchemy and Moralis, to fetch live blockchain data and token price information, enhancing the bot’s decision-making process.
- Implemented in-memory caching mechanisms to optimize API calls, reducing redundant queries by 80% and improving overall system performance.
- Designed and built a secure web interface with basic authentication for managing bot configurations and monitoring performance metrics in real time.
- Engineered a robust server restart mechanism that gracefully handles configuration changes, ensuring minimal downtime and consistent service availability.
- Optimized transaction processing logic to filter out non-profitable or high-risk transactions, leading to a 30% increase in successful exploitations.
- Created a comprehensive error-handling system that logs failures, analyzes patterns, and provides detailed statistics, enabling data-driven improvements to the bot's strategy.
- Enhanced system security by caching and rejecting suspicious token addresses, mitigating risks associated with spam, unverified contracts, and low-liquidity tokens.
- Streamlined the bot deployment process by automating environment variable management and integrating seamless server reloads upon configuration updates.
- Ensured compliance with best practices in smart contract interaction by implementing gas estimation techniques and optimizing transaction fees.
Blockchain Expert
TapRoots Wisdom, Inc.
- Led the strategic planning and development of the TORC tokens and TapRoots Wisdom games ecosystem, ensuring alignment with the project's vision.
- Developed a comprehensive roadmap that outlines key milestones, deadlines, and deliverables, resulting in a clear path forward for the project.
- Designed the website wireframe and user experience, focusing on clean, concise, and engaging content that enhances user interaction.
- Created compelling one-liners and content for the website, increasing user engagement and brand clarity by 25%.
- Managed the tokenomics structure, ensuring a balanced and sustainable economic model that supports long-term growth and user retention.
- Coordinated a cross-functional team of designers, developers, and marketers to ensure timely delivery of project components, achieving a 100% on-time delivery rate.
- Authored detailed problem-solution presentations, effectively communicating the project’s value proposition to stakeholders and potential investors.
- Implemented a community engagement strategy, increasing community involvement and feedback by 40%.
- Reviewed and revised the project's white paper, enhancing clarity and ensuring all technical details were accurately represented.
- Monitored project progress and KPIs, providing regular updates to stakeholders and ensuring alignment with project goals.
ERC Auditing and Deployment Specialist
SIMBA Token
- Conducted detailed security audits of the ERC20 token's smart contracts successfully, identifying and rectifying vulnerabilities to ensure robust security against hacks and fraud.
- Developed and implemented best practices for smart contract development and auditing, significantly enhancing the token's reliability and trustworthiness in the blockchain community.
- Designed and executed innovative risk management strategies, effectively mitigating potential financial and operational risks associated with the ERC20 token.
Solidity Developer
Kondux LLC
- Architected the blockchain infrastructure for Kondux, including creating ERC721 NFTs NVidia Omniverse metaverse-ready.
- Designed and implemented whitelist minting contracts and systems.
- Helped Kondux establish itself as a leading design lab in the Web3 space, specializing in 3D NFT marketplaces, AR/VR/XR environments, metaverse design, manufacturing models, and gaming experiences.
- Designed and implemented staking smart contracts for the company's clients, enabling them to earn rewards for holding and supporting specific tokens.
- Connected the company's blockchain assets to NVidia Omniverse, enabling clients to experience their digital assets in immersive, real-time 3D environments.
- Collaborated on the development of Kondux's tokenomics, creating a sustainable and effective system for incentivizing participation and value creation within the company's ecosystem.
- Documented and tested the smart contract basecode, ensuring accuracy, efficiency, and security in the company's blockchain solutions.
Smart Contracts Developer
Alpha Lease Management LLC
- Developed decentralized finance (DeFi) smart contracts with DAO governance, bonds, and staking. This project was inspired by OlympusDAO. I've used Hardhat as the main framework.
- Created a full CI/CD with full test coverage and autonomous deployment.
- Upgraded some clients' legacy contracts to more secure versions while keeping functionality and migrating assets.
Senior Solidity Developer
Banyan Storage Inc.
- Designed a decentralized storage provider marketplace, agnostic to any storaging (IPFS, S3, etc.) and type of crypto payment (ERC20, ERC721, ERC1155) as collateral.
- Developed contracts for the company's MVP, with full testing, deployment scripts, and CI/CD pipeline using Hardhat and GitHub Actions. (https://github.com/banyancomputer/contracts).
- Conducted regular code reviews and provided mentorship and feedback to junior engineers, resulting in an increase in team productivity and a reduction in code defects.
- Stayed up-to-date with the latest trends and best practices in blockchain and distributed systems and shared this knowledge with the team through regular training and knowledge-sharing sessions.
- Created and maintained technical documentation, including API specifications and user guides, reducing the time required to onboard new developers and users to the platform.
- Worked closely with product managers and other stakeholders to identify and translate key business requirements into technical specifications.
CTO
Blockchain Studio
- Developed a token for the Brazillian government to track state loans and fight corruption. This project used Bitcoin, Lightning Network, and RGB stack.
- Created an NFT-based game with a marketplace for users to auction their NFTs. This project used the Ethereum and Polygon stack.
- Started adopting the agile culture in the company, teaching and implementing frameworks like the OKR, Large Scale Scrum (LeSS), and Holacracy.
Software Engineer
Knowledge21
- Developed a classroom scheduler system. The project used PHP and a WordPress framework.
- Built a chatbot for Zendesk to increase the SLA and NPS of the company's help desk.
- Led one of the company's strategic and tactical OKRs cycle of 2020.
Tech Leader
Kiina.Ai
- Developed several chatbots using Facebook, Twitter, and Zendesk API.
- Built a custom integration for the Consumidor.Gov website to plug in a chatbot.
- Created these chatbots that had near 100,000 chats with users per month.
- Developed a dashboard with the chatbot's usage statistics and insights.
Blockchain Developer
55.com
- Created a CI/CD pipeline for the exchange system on Gitlab.
- Helped the quality assurance team create and automate the tests for the company's software.
- Helped the blockchain team to develop smart contracts for the company's tokens.
Blockchain Engineer
Apus Payments
- Developed a cryptocurrency payment system that used the credit card number (fingerprint) as the seed of a custom, in-house, Crypto HD Wallet.
- Developed a crypto HD wallet for Bitcoin, Bitcoin Cash, Decred, and Litecoin.
- Developed an API to communicate blockchain full nodes to POS that received payments in crypto.
- Created an intelligent fee estimator for Bitcoin that watched the mempool for the probable minimum fee for a 1-block mining time for a transaction.
- Created a system that cached and batched different platform costumer's transactions to the Bitcoin blockchain to save on fees.
Experience
UNICEF's Giga
http://giga.globalBy connecting schools, Giga provides opportunities for students to develop digital skills and access online learning content while creating anchor points for communities to access local businesses and services. The initiative combines the expertise of UNICEF in education and procurement, ITU's knowledge of regulation and policy, and private-sector technology solutions.
As a blockchain engineer, I have contributed to securing donations and tracking grants using blockchain technology. Giga is the only initiative for connectivity named in the UN Secretary-General's Digital Cooperation Roadmap and Common Agenda. It operates under UNICEF's Office of Innovation and ITU's Telecommunication Development Bureau.
Kondux
http://kondux.infoBanyan Decentralized Storage Marketplace
https://github.com/banyancomputer/contractsWhy Banyan?
• Security: the safety of decentralized storage with exceptional censorship-resistant privacy features.
• Longevity: incentive IPFS paid on the chain to ensure your data will be stored safely as long as the user wants.
• User-friendliness: effortless advanced file management features with a web interface and API.
Futster.io
https://futster.ioI've submitted this project to Certik's auditory, supervised, and implemented their recommendations to get a 90+ score.
The cool part: the game is fully decentralized regarding the custody of the assets but centralized on game rules and mechanics. We achieved an effortless onboarding as playing the game doesn't require the player to have cryptocurrencies. I designed the system to act like a "concierge," catching and submitting the transactions on behalf of the player. This project also had CI/CD for smart contracts with Hardhat and Gitlab pipelines, compilation, testing, deployment, and verification.
Gov Token
Apus Payments
https://www.youtube.com/channel/UCrNKH83d14ZYcpsufht4lyA/featuredVacinaAcao
https://github.com/VacinaAcaoVacinaAcao uses Ethereum smart contract for the back end and a Web3 mobile app.
Ether Box
https://github.com/etherbox/etherboxNode.js Bitcoin Library
https://github.com/marco-jardim/bitcoin-libEducation
Ph.D. Degree in Computer Science
Rio de Janeiro's Federal University (UFRJ/IESC) - Rio de Janeiro, Brazil
Master's Degree in Digital Currencies and Blockchain
University of Nicosia (UNic) - Nicosia, Cyprus
Bachelor's Degree in Computer Science
Rio de Janeiro's Federal University (UFRJ/DCC) - Rio de Janeiro, Brazil
Certifications
Azure AI Fundamentals
Microsoft
R Programming
Coursera
The Data Scientist’s Toolbox
Coursera
Getting and Cleaning Data
Coursera
Exploratory Data Analysis
Coursera
Skills
Libraries/APIs
Node.js, Web3.js, Chai, REST APIs, OpenZeppelin, Liquid, Binance API, React
Tools
Ganache, BTC Wallet, MetaMask, BigQuery, GitHub, Git, GitLab, GitLab CI/CD, VPN
Languages
Solidity, JavaScript, TypeScript, HTML, SQL, Python, Java, R, HTML5, PHP, Rust, GraphQL, Go, CSS, C++
Frameworks
Hardhat, Truffle, Express.js
Paradigms
Agile Project Management, Scrum, Agile, ETL, High-performance Computing (HPC), Distributed Computing, DevOps, Testing, Test-driven Development (TDD), Microservices, Server-side Programming, Fuzz Testing, Object-relational Mapping (ORM)
Platforms
Linux, Ethereum, Blockchain, Blockchain Platforms, Amazon Web Services (AWS), Decentralized Exchanges (DEXs), Avalanche, Chainlink, Oracle, Google Cloud Platform (GCP), Mobile, Hyperledger, WordPress, Twilio, Telegram Bot Platform, Hyperledger Fabric, Zendesk, Azure, Magento, Android, iOS
Storage
DB, Google Cloud, MySQL, NoSQL, Databases, Redis, PostgreSQL, MongoDB, CouchDB
Industry Expertise
Cybersecurity, Trading Systems, Project Management
Other
Bitcoin, Lightning Network, DApps, Decentralized Finance (DeFi), Data Science, Artificial Intelligence (AI), Sidechains, Non-fungible Tokens (NFT), Google BigQuery, Cryptocurrency, Scraping, Cryptography, Digital Signatures, Bitcoind, Blockchain as a Service, Blockchain & Cryptocurrency, ERC-1155, Elliptic Curve Cryptography, Decentralization, Decentralized Autonomous Organizations (DAO), Zero-knowledge Proofs, Token Design, Tokenization, Ethers.js, Smart Contracts, Ethereum Smart Contracts, Litecoin, HD Wallets, Cryptocurrency Wallets, ERC-721, Liquidity Pools, Exploratory Data Analysis, Data Cleaning, Data Recovery, Statisticians, Architecture, ÐApp, Technical Project Management, Cloud Services, Back-end, Cryptocoin Mining, APIs, IPFS, Web Security, Security, IT Security, Distributed Systems, Team Management, Team Leadership, Decentralized Systems, Solana, Infrastructure, Infrastructure as Code (IaC), Payment APIs, Crypto, Consensus Mechanism, Web 3.0, Concurrency, Memory Management, Applied Cryptography, Advisory, Project Consultancy, Networks, ERC-20, Blockchain Design, Loyalty Programs, Customized Blockchains, Enterprise Loyalty Programs, Leadership, Digital Asset Management, Fractionalization, ICO, Cryptocurrency Exchanges, Polygon EVM, Back-end Development, Sepolia, Web3, API Integration, Foundry, Utility Tokens, Data Queries, Analytics, Algorithms, Off-chain Development, Ledgers, Troubleshooting, Auditing, Uniswap V2, Reflection Tokens, Security Audits, Distributed Hash Tables (DHT), Consensus Algorithms, Networking, Mining, Threat Analytics, Vulnerability Management, Decentralized Applications, Bots, Distributed Ledger Technology (DLT), Computer Science, White Papers, GPU Computing, Technical Writing, Ethereum Virtual Machine (EVM), Software Architecture, Obfuscation, Trading Bots, Audits, P2P, Tokenomics, CI/CD Pipelines, Big Data, RGB Protocol, zkSNARKs, Polygon, Card Payments, Digital Payments, Credit Cards, Mobile Wallet, Cloud, Full-stack, CTO, Scrum Master, GDPR, Arbitrage, Flash Loans, Content Creation, Internet of Things (IoT), Stock Exchange, Telegram Bots, Parsers, Compilers, Biomedical Skills, SysOps, Web Development, Writing & Editing, PoWH3D, Microsoft Azure, Economics, Exchanges, Cryptocurrency Payments, Graphs, District Health Information Software (DHIS), Open Source, Game Theory, Libraries, RPC, Front-end, Trading, High Code Quality, Storage, Secure Storage, Validation, User Validation, Mobile Advertising, Aptos, Cosmos, Internet Computer Protocol (ICP)
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