Octavian is available for hire
Hire OctavianOctavian Lojnita
Verified Expert in Engineering
Full-stack Developer
Constanța, Romania
Toptal member since April 22, 2022
Bio
Octavian, an accomplished software polymath, has 20+ years of experience in networking, security, apps, websites, blockchains, and emerging technologies like AI. His expertise in app development, iOS games, custom web systems, and fintech propelled numerous projects to success in both the Web 2.0 and Web 3.0 realms. Leveraging his profound knowledge, Octavian pushes the frontiers of blockchain technologies, fostering innovation within all his expertise.
Portfolio
Progressive Web Apps
Blockchain, Cryptocurrency, Non-fungible Tokens (NFT), ICO, Sidechains...
Psalm, LLC (dba Psalm DAO)
Blockchain, Smart Contracts, CTO, Non-fungible Tokens (NFT), Cryptocurrency...
Opus Momentus Proprietary Limited
Blockchain, Tokenomics, Cryptocurrency Wallets, Product Growth, SQL, Oracle...
Experience
- Full-stack - 14 years
- Blockchain - 11 years
- Ethereum - 8 years
- Solidity - 8 years
- DApps - 8 years
- Audits - 7 years
- React - 7 years
- Decentralized Finance (DeFi) - 5 years
Work Experience
Chief Technical Officer
2018 - PRESENT
Progressive Web Apps
- Developed back-end and front-end solutions for clients that required KYC and AML expertise. I developed the back end in Node.js and the front end in React.
- Built ERC20 tokens, ERC677 tokens for multiple clients, and ICO campaigns with multistage vesting emissions. In the past year, we focused on building DAOs and voting systems in which proposers, voters, and executers maintain the community treasury.
- Helped a few local artists launch their independent and ERC721 NFT collections. A few of the NFTs provided access to a private website section that allowed only private members to join.
- Built multiple projects that used ERC721 and ERC1155 to incentivize a private community focused on DAO governance.
- Developed solutions that revolved around Chainlink and APIs to ensure on-chain whitelisting and revalidation for existing members.
- Integrated Chainlink Price Feeds into multiple ICOs to provide full conversion in USD for every major supported cryptocurrency. This ensured strict USD limits that were compliant with KYC and AML rules.
- Contributed to the Loom Network interoperable bridges and universal wallets.
- Integrated more than 30 non-custodial wallets inside front ends.
Technologies: Blockchain, Cryptocurrency, Non-fungible Tokens (NFT), ICO, Sidechains, JavaScript, Smart Contracts, Web3.js, Ethereum Smart Contracts, ERC-721, Decentralized Applications, Node.js, Fintech, Decentralized Finance (DeFi), JSON-RPC, Cryptocurrency Wallets, Blockchain & Cryptocurrency, Ethers.js, Blockchain Design, MetaMask, HTML, CSS, TypeScript, Full-stack, Security, Architecture, Banking & Finance, Express.js, IT Security, IPFS, API Architecture, Blockchain Platforms, Blockchain Game Development, Next.js, Distributed Systems, Vercel, Audits, Ethereum, Team Management, Scrum, Agile, Scrum Master, Team Leadership, Agile Project Management, Project Management, APIs, IT Infrastructure, Solidity, Crypto, Software, Arbitrage, Decentralization, Flash Loans, Decentralized Exchanges (DEXs), Integration, API Integration, Go, Decentralized Systems, Software Architecture, Amazon Web Services (AWS), Microservices, Bots, Trading, Tokenization, Quality Assurance (QA), QA Automation, QA Leadership, QA Testing, Manual QA, Utility Tokens, Technical Leadership, Technical Requirements, Estimations, Web 3.0, GitHub, ERC-1155, ERC-20, Twilio, Healthcare Services, React, RPC, WebSockets, P2P, Advisory, Project Consultancy, DApps, MySQL, Python, Web Development, Algorithms, Software Engineering, Front-end, WebAssembly (Wasm), Webhooks, Stock Exchange, CTO, Leadership, Digital Asset Management, Fractionalization, DigitalOcean, Cryptocurrency Exchanges, NoSQL, Back-end Development, Blockchain as a Service, Jira, Parsers, Fuzz Testing, Compilers, Web3, Casinos & Gaming, Gambling, Tailwind CSS, Public Finance, Back-end, Sequelize, Product Growth, SQL, Oracle, Foundry, Web Scraping, API Development, GraphQL, Push Notifications, Biomedical Skills, Token Design, Databases, HTML5, Ledgers, Off-chain Development, Troubleshooting, Auditing, Binance API, GRAPH, ÐApp, Marketplaces, MultiChain, Kubernetes, Vue, CI/CD Pipelines, Scripting, Ethereum Virtual Machine (EVM), Full-stack Development, Microservices Architecture, Applied Cryptography, Test Scripting, token airdrop, Distributed Ledger Technology (DLT), Avalanche, White Papers, Computer Science, Cryptography, Cybersecurity, Geth (go-ethereum), Technical Writing, Distributed Computing, Apps, Quantitative Finance, Linux, Etherscan, Front-end Development, User Interface (UI), User Experience (UX), SCSS, UTXO, Cryptocurrency APIs, Chrome Extensions, Data Science, KVM, VirtualBox, Blockchain Architecture, Cosmos SDK, Mathematics, Large-scale Distributed Systems, Distributed Software, Vendor Management, Content Writing, Writing & Editing, Algorithmic Trading, Uniswap, Uniswap V2, Uniswap SDK, Trading Bots, Liquidity Pools, Solidity Assembly, cross chain, Swaps, Aggregators, Binance Smart Chain (BSC), Automated Market Makers (AMM), Subgraph, JSON, Payment Gateways, Payment Processing, Rust, AirDrop, QR Codes, Cryptocurrency Trading, Maximal extractable value (MEV), Remix IDE, Huff, Documentation, WalletConnect, Arweave, Agile Software Development, MEV bots, Maximal Extractable Value (MEV), Lending, Filecoin, Real Estate, Project Budget Management, Project Discovery, NFT Design, Website Integration, Squarespace, Plaid, Plaid API, gRPC, Java, Digital Payments, Payment Systems, Payment Solutions, Solana, Solution Architecture, Blockchain Development, Artificial Intelligence (AI), Quantum Computing, Crypto++, Credit Card Processing, Credit Cards, High-risk Credit Card Processing, PCI DSS, TradingView, Bybit, Binance Cryptocurrency Exchange, Common Crypto, Ethereum Plasma, OpenZeppelin, Permit2, Code Review, Product Owner, System Architecture, Cloud, Terraform, Docker, Continuous Integration (CI), Deployment, Platform Engineering, Telegram Bots, AWS Cloud Operations, Red Hat Linux, High-frequency Trading (HFT), Data Pipelines, Performance Optimization, Real-time Data, Hyperliquid, Drift, Google Cloud Platform (GCP), Backtesting, Data Handling, CSV File Processing, Quantitative Risk Modeling, Backtesting Trading Strategies, Trading Strategy Development, Data Vaults, Prisma, Mapbox, Health, Identity & Access Management (IAM), Compliance, Slack, Google Workspace, Google Drive, Email Automation, Card Payments, CRM Systems, Zapier, SMS Bots, Airtable, Stripe, Enterprise Architecture, AI Integration, Large Language Models (LLMs), OpenAI, Stablecoins, Metrics, Data Analysis, A/B Testing, Concurrent Programming, Startups, Minimum Viable Product (MVP), Escrow, Prediction Markets, Hash, Deterministic Encryption, Azure, VRF, Anchor, NestJS, Event-driven Architecture, ERC-8004, Payments, Fractional CTO, Amazon EC2, Prompt Engineering, Claude, LLM Integration, AI Agent Orchestration, AI Agents, Agentic AI, Claude Code, Gemini, Model Context Protocol (MCP), Vertex AI, Role-based Access Control (RBAC), Virtual Machines, Networking, Virtual Environments, Unix/Linux Virtualization, VMware, Memory Management, Virtualization, AI Security, Data Security, Web Security, App Infrastructure, Cloud Infrastructure, Enterprise Infrastructure, Infrastructure Monitoring, Infrastructure Automation, Immutable Infrastructure, Infrastructure Security, Network Security, Customer Identity and Access Management (CIAM), Capital Markets, Venture Capital, External Audits, Audit Testing, Website Audits, IT Audits, Code Auditing, SEO Audits, Apple Pay, Google Pay, Industrial Automation Communication Protocols, Protobuf, Automation, Application State Management, Redux, Responsive UI, Zustand, Jest, Blockchain Wallets, Monitoring, Transactions, Oracle Configure, Price and Quote (CPQ) Cloud, Open-source LLMs, Risk & Compliance.Auditing, Controllership/Accounting.External Financial Reporting, Industry.Finance.Financial Modeling.Financial Statements, Advisory.Business Advisory.Valuation, Tests of Controls, Technical Accounting, SOX Compliance, SOX
Chief Technology Officer, Blockchain
2023 - 2023
Psalm, LLC (dba Psalm DAO)
- Reduced ERC721 smart contract IT costs to around 13 MATIC on Polygon to mint 20,000 NFTs.
- Lowered gas fees to around 0.0005 MATIC for the same batch of 20,000 NFTs after upgrading the codebase to ERC721A.
- Helped configure and deploy Next.js and Vercel for the website.
- Managed two teams and mentored developers on using the Ethereum virtual machine (EVM) to help them use newer EVM tricks more efficiently to reduce gas costs.
Technologies: Blockchain, Smart Contracts, CTO, Non-fungible Tokens (NFT), Cryptocurrency, DigitalOcean, Security, Oracle, Token Design, Data Queries, Redis, HTML5, Troubleshooting, ÐApp, CI/CD Pipelines, Scripting, Ethereum Virtual Machine (EVM), Full-stack Development, Microservices Architecture, Architecture, Applied Cryptography, Distributed Ledger Technology (DLT), White Papers, Computer Science, Cryptography, Cybersecurity, Geth (go-ethereum), Etherscan, Front-end Development, User Interface (UI), User Experience (UX), Mathematics, Large-scale Distributed Systems, Distributed Software, JSON, AirDrop, Project Discovery, NFT Design, Website Integration, Crypto++, Common Crypto, Ethereum Plasma, Cloud, Docker, Deployment, Platform Engineering, Startups, Minimum Viable Product (MVP), Escrow, Hash, NestJS, Event-driven Architecture, Fractional CTO, Memory Management, Virtualization, App Infrastructure, Website Audits, IT Audits, Responsive UI, Transactions, Advisory.Business Advisory.Valuation, Tests of Controls
Blockchain Expert
2023 - 2023
Opus Momentus Proprietary Limited
- Built a fully functional cross-chain hedge with six core features: wallet creation, staking, deposits, relayer, aggregator, and withdrawal.
- Created the back end and fault tolerance using two mirror databases: relational and non-relational.
- Developed deposit tracking using Alchemy SDK and deposits aggregator contracts deployed on each chain.
Technologies: Blockchain, Tokenomics, Cryptocurrency Wallets, Product Growth, SQL, Oracle, API Development, Token Design, Databases, PostgreSQL, HTML5, Ledgers, Off-chain Development, Troubleshooting, Auditing, ÐApp, MultiChain, Kubernetes, CI/CD Pipelines, Scripting, Ethereum Virtual Machine (EVM), Full-stack Development, Microservices Architecture, Architecture, Applied Cryptography, Test Scripting, Distributed Ledger Technology (DLT), White Papers, Computer Science, Cryptography, Cybersecurity, Geth (go-ethereum), Apps, Linux, Etherscan, Front-end Development, User Interface (UI), User Experience (UX), SCSS, Cryptocurrency APIs, Data Science, Mathematics, Large-scale Distributed Systems, Algorithmic Trading, Uniswap, Uniswap V2, Uniswap SDK, Trading Bots, Automated Market Makers (AMM), JSON, Payment Gateways, Payment Processing, Cryptocurrency Trading, Documentation, MEV bots, Maximal Extractable Value (MEV), Project Discovery, Website Integration, Payment Solutions, Crypto++, Credit Cards, Common Crypto, Ethereum Plasma, Code Review, Cloud, Docker, Deployment, Platform Engineering, High-frequency Trading (HFT), Go, Performance Optimization, Data Handling, Backtesting Trading Strategies, Identity & Access Management (IAM), Google Workspace, Google Drive, Email Automation, Data Analysis, A/B Testing, Startups, Minimum Viable Product (MVP), Escrow, Event-driven Architecture, Fractional CTO, Role-based Access Control (RBAC), Virtual Machines, Memory Management, App Infrastructure, Website Audits, IT Audits, Code Auditing, Automation, Web3.py, Application State Management, Blockchain Wallets, Monitoring, Transactions, Oracle Configure, Price and Quote (CPQ) Cloud, Risk & Compliance.Auditing, Controllership/Accounting.External Financial Reporting, Industry.Finance.Financial Modeling.Financial Statements, Advisory.Business Advisory.Valuation, Tests of Controls, Technical Accounting, SOX Compliance, SOX
Blockchain Expert
2023 - 2023
Hoichi
- Developed a Solidity smart contract for Hoichi DAO to distribute prizes incurred from the Hoichi Token Uniswap buy and sell fees to their 369 ERC-721 NFT holders.
- Built the raffle to support the Chainlink VRF self-subscription method.
- Tested on Sepolia, simulated on Mainnet, and created the deployment configuration.
- Deployed the raffle to Ethereum Mainnet successfully.
- Passed all audits with flying colors—no issues found.
Technologies: Blockchain, Chainlink, Smart Contracts, Solidity, Parsers, Fuzz Testing, Compilers, Web3, Casinos & Gaming, Public Finance, Back-end, Oracle, Foundry, HTML5, Troubleshooting, Auditing, ÐApp, Scripting, Ethereum Virtual Machine (EVM), Full-stack Development, Microservices Architecture, Architecture, Applied Cryptography, Distributed Ledger Technology (DLT), Computer Science, Cryptography, Etherscan, Mathematics, Project Discovery, NFT Design, Website Integration, Crypto++, Common Crypto, Ethereum Plasma, Docker, Deployment, Platform Engineering, Data Handling, Startups, Minimum Viable Product (MVP), Escrow, VRF, IT Audits, Transactions
Blockchain Lead
2022 - 2022
Freelance Client
- Discovered multiple critical vulnerabilities and logic flaws in multiple projects that the team was working on and helped protect and migrate liquidity to safe versions.
- Created a thorough security report detailing the problems discovered and mitigation steps with scenario outcome recommendations.
- Rewrote the v1 codebase into the most gas-efficient version with native MEV Protection.
- Innovated trading protection features and OTC Token sales. Led auditing, testing, deployments, and liquidity migrations that covered all edge cases and successfully migrated all vulnerable liquidity using flashbots and shielded transactions.
- Added protected transactions to prevent MEV bots from executing a sandwich attack on users by draining their slippage tolerance.
- Added a check that enforces multi-transfers only to be done once per block by each user when transferring and thus prevented MEV bots from making arbitrage and transaction reordering plays.
- Performed a lot of planning, rewrites, dead code, and improved gas costs to the latest versions with no technical debt.
- Made a snapshot of balances for V1 and minted an equal amount in V2 contracts.
- Helped coordinate with team members and assisted them in creating local forks and Gnosis treasury proposals, votes, and quorum executions via Flashbots.
- Trained three developers on how to do mainnet fork and simulations. Created scripts to extract liquidity and do the migrations successfully.
Technologies: Blockchain, Solidity, Team Management, Scrum, Agile, Scrum Master, Web3.js, Team Leadership, Agile Project Management, Project Management, Integration, API Integration, Memory Pools, Decentralized Systems, Software Architecture, REST APIs, Microservices, Bots, Tokenization, Quality Assurance (QA), QA Automation, QA Leadership, QA Testing, Manual QA, Utility Tokens, Technical Leadership, Technical Requirements, Estimations, Web 3.0, GitHub, ERC-20, Twilio, React, Next.js, JavaScript, Full-stack, RPC, WebSockets, P2P, Advisory, Project Consultancy, Go, DApps, Audits, Ethereum, Web Development, Algorithms, Software Engineering, Front-end, Webhooks, Stock Exchange, CTO, Leadership, Digital Asset Management, Exchanges, Fractionalization, NoSQL, Back-end Development, Jira, Parsers, Fuzz Testing, Compilers, Web3, Casinos & Gaming, Gambling, Tailwind CSS, Public Finance, Back-end, Product Growth, Oracle, API Development, Token Design, HTML5, Troubleshooting, Auditing, GRAPH, ÐApp, Scripting, Full-stack Development, Microservices Architecture, Applied Cryptography, Test Scripting, Distributed Ledger Technology (DLT), Computer Science, Cryptography, Cybersecurity, Linux, Etherscan, Front-end Development, User Interface (UI), User Experience (UX), SCSS, Mathematics, Vendor Management, Uniswap, Uniswap V2, Uniswap SDK, JSON, QR Codes, Cryptocurrency Trading, WalletConnect, Agile Software Development, Project Discovery, Website Integration, Payment Solutions, Blockchain Development, Crypto++, Common Crypto, Ethereum Plasma, Code Review, Product Owner, System Architecture, Cloud, Docker, Deployment, Platform Engineering, Performance Optimization, Data Handling, Concurrent Programming, Startups, Minimum Viable Product (MVP), Escrow, Hash, Event-driven Architecture, Fractional CTO, IT Audits, Code Auditing, Application State Management, Blockchain Wallets, Transactions, Risk & Compliance.Auditing, Controllership/Accounting.External Financial Reporting, Industry.Finance.Financial Modeling.Financial Statements, Advisory.Business Advisory.Valuation, Tests of Controls, Technical Accounting
Expert Smart-contract Blockchain Developer
2022 - 2022
Freelance Clients
- Created MultiCall contracts, tests, and protected transactions.
- Handled Alchemy scripts and Flashloans private transactions relayed to the Flashbots bundlers to minimize MEV Bots from reading the transactions in the memory pool and doing frontrunning, sandwich attacks, arbitrage, and flash loans.
- Built forks, setups, tests, and local fork simulations.
Technologies: Solidity, Blockchain, Smart Contracts, Decentralized Finance (DeFi), Integration, API Integration, Memory Pools, Software Architecture, Microservices, QA Testing, Manual QA, Utility Tokens, Estimations, Web 3.0, GitHub, ERC-20, Twilio, React, Next.js, Web3.js, Full-stack, RPC, WebSockets, P2P, Advisory, Project Consultancy, DApps, Audits, Ethereum, Web Development, Algorithms, Software Engineering, Front-end, Webhooks, Leadership, Digital Asset Management, Exchanges, Fractionalization, NoSQL, Back-end Development, Parsers, Fuzz Testing, Compilers, Web3, Tailwind CSS, Fantom, Public Finance, Back-end, Oracle, API Development, HTML5, Troubleshooting, Binance API, Scripting, Ethereum Virtual Machine (EVM), Full-stack Development, Microservices Architecture, Applied Cryptography, Test Scripting, Distributed Ledger Technology (DLT), Computer Science, Cryptography, Cybersecurity, Quantitative Finance, Etherscan, Front-end Development, User Interface (UI), User Experience (UX), Mathematics, Algorithmic Trading, Uniswap, Uniswap V2, Uniswap SDK, Trading Bots, Cryptocurrency Trading, Documentation, MEV bots, Maximal Extractable Value (MEV), Project Discovery, Blockchain Development, Crypto++, Common Crypto, Ethereum Plasma, Deployment, Platform Engineering, High-frequency Trading (HFT), Startups, Minimum Viable Product (MVP), Escrow, SEO Audits, Automation, Transactions, Tests of Controls
Senior Full-stack Developer
2018 - 2018
Fii pe net
- Trained five junior colleagues, which allowed us to reduce deployment times and increase productivity.
- Built and maintained a big data real estate data scraper that made cross-referenced filters for the LIFA Denmark API using TypeScript.
- Developed numerous WordPress websites and maintained their security.
- Handled SEO growth hacks and ensured our audit coverage was always up to date.
Technologies: Websites, React, WordPress, Design, APIs, JavaScript, Web3.js, Ethereum Smart Contracts, Node.js, JSON-RPC, Blockchain Design, MetaMask, HTML, CSS, TypeScript, Full-stack, DevOps, Express.js, IT Security, API Architecture, Blockchain Platforms, Blockchain Game Development, Distributed Systems, Team Management, Scrum, Agile, Team Leadership, Agile Project Management, Project Management, Chainlink, Cryptocurrency Wallets, Infrastructure, IT Infrastructure, Solidity, Crypto, Software, ERC-20, Smart Contracts, Amazon Web Services (AWS), Integration, API Integration, Software Architecture, REST APIs, Microservices, Bots, Trading, QA Automation, QA Testing, Web 3.0, Netlify, GitHub, Healthcare Services, RPC, WebSockets, VPN, P2P, Project Consultancy, Networks, Go, DApps, Audits, Blockchain, MySQL, Web Development, Algorithms, Software Engineering, Front-end, Webhooks, NoSQL, Back-end Development, Parsers, Compilers, Web3, Public Finance, Back-end, Web Scraping, API Development, Push Notifications, Databases, PostgreSQL, Data Queries, Redis, HTML5, Troubleshooting, ÐApp, Scripting, Full-stack Development, Microservices Architecture, Applied Cryptography, Truffle, Test Scripting, Computer Science, Cryptography, Geth (go-ethereum), Linux, Front-end Development, User Interface (UI), User Experience (UX), Cryptocurrency APIs, Chrome Extensions, Data Science, KVM, VirtualBox, Mathematics, Documentation, Project Discovery, Website Integration, Squarespace, Product Owner, System Architecture, Cloud, Docker, Deployment, Platform Engineering, PHP, Email Automation, Card Payments, CRM Systems, Concurrent Programming, Startups, Minimum Viable Product (MVP), Escrow, Role-based Access Control (RBAC), App Infrastructure, External Audits, Website Audits, IT Audits, Apple Pay, Google Pay, Responsive UI, Risk & Compliance.Auditing, Controllership/Accounting.External Financial Reporting, Industry.Finance.Financial Modeling.Financial Statements, Tests of Controls, Technical Accounting
API Developer
2015 - 2017
AWC LLC
- Developed the front end and integrated wallets using BitGo APIs that enabled crypto payments within the platform.
- Started an experiment that turned into a non-custodial wallet by building a PIN-password lock/unlock feature that allowed discovery and self-recovery of the private key using the Curve25519-based algorithm.
- Built the API that handled the Magento and Shopify plugins and open-source plugins used by developers to handle big data processing for payment solutions.
- Owned full responsibility for development environments and product deployments.
Technologies: Blockchain, Payment APIs, Ethereum, Bitcoin, JavaScript, Smart Contracts, Web3.js, Ethereum Smart Contracts, Node.js, Fintech, JSON-RPC, Ethers.js, Blockchain Design, MetaMask, HTML, CSS, Full-stack, DevOps, Banking & Finance, Express.js, IT Security, API Architecture, Blockchain Platforms, Distributed Systems, Scrum, Agile, Scrum Master, Team Leadership, Agile Project Management, Project Management, APIs, Chainlink, Cryptocurrency Wallets, IT Infrastructure, Solidity, Crypto, Software, Decentralization, Integration, API Integration, Go, Software Architecture, REST APIs, Amazon Web Services (AWS), QA Automation, Utility Tokens, Netlify, GitHub, Healthcare Services, RPC, WebSockets, TypeScript, VPN, P2P, Advisory, Project Consultancy, Networks, DApps, MySQL, Python, Web Development, Algorithms, Software Engineering, Front-end, NoSQL, Back-end Development, Parsers, Compilers, Web3, Public Finance, Back-end, API Development, Databases, PostgreSQL, Data Queries, Redis, HTML5, Troubleshooting, Scripting, Full-stack Development, Microservices Architecture, Applied Cryptography, Test Scripting, Computer Science, Cryptography, Cybersecurity, Geth (go-ethereum), Linux, UTXO, Cryptocurrency APIs, Data Science, KVM, Blockchain Architecture, Mathematics, Distributed Software, QR Codes, Remix IDE, Documentation, Project Discovery, Website Integration, Payment Systems, Payment Solutions, Blockchain Development, Crypto++, Common Crypto, Ethereum Plasma, Cloud, Deployment, Platform Engineering, Data Pipelines, Performance Optimization, Real-time Data, CSV File Processing, PHP, Compliance, Email Automation, Card Payments, A/B Testing, Concurrent Programming, Startups, Minimum Viable Product (MVP), Escrow, Amazon EC2, Memory Management, Cloud Infrastructure, IT Audits, Code Auditing, SEO Audits, Monitoring, Transactions, Risk & Compliance.Auditing, Controllership/Accounting.External Financial Reporting, Industry.Finance.Financial Modeling.Financial Statements, Tests of Controls, Technical Accounting
iOS App Developer
2014 - 2015
iSecurity LLC
- Built an app using Objective-C with video, audio streaming, and access to CCTV cameras that displays employee schedules and tracks and audits schedules.
- Managed multiple clones of the same app for different clients, increasing management and productivity while making time-consuming tasks easy to perform.
- Took responsibility for auditing every update before publishing.
- Helped developers ship faster by maintaining environments and ensuring tight security.
Technologies: Objective-C, iOS, MongoDB, Security, Architecture, DevOps, IT Security, Cryptocurrency Wallets, IT Infrastructure, Solidity, Crypto, Software, Integration, API Integration, Software Architecture, Trading, GitHub, Networks, Algorithms, Software Engineering, Front-end, Parsers, Compilers, Web Scraping, API Development, Databases, PostgreSQL, HTML5, Troubleshooting, Full-stack Development, Applied Cryptography, Computer Science, Cryptography, Apps, Linux, User Experience (UX), VirtualBox, Mobile, Base Blockchain, QR Codes, Documentation, Project Discovery, Website Integration, Deployment, Platform Engineering, C++, Data Pipelines, Performance Optimization, Real-time Data, Compliance, CRM Systems, Concurrent Programming, Startups, Minimum Viable Product (MVP), Escrow, Data Security, App Infrastructure, Cloud Infrastructure, Network Security, External Audits, IT Audits, Automation, Transactions, Risk & Compliance.Auditing
Project History
Freed Finance
The world’s first DeFi SuperApp. Self-custodial. Borderless. Everyone is a merchant. Absolute financial freedom.
Freed abstracts away blockchain complexity, so users can focus on what matters, with everything they need and nothing they don’t.
FEATURES
• Spend Yield, Keep Crypto
The card that lets you fund purchases with your portfolio growth. Never sell your principal asset unnecessarily.
• Aggregated Liquidity
Retail swaps are often inefficient. Freed aggregates liquidity from top DEXs to give you optimized pricing on every trade.
• The Financial Social Network
Money is social. Freed turns your contact list into a decentralized payment network. Send USD, EUR, or ETH as easily as a DM.
• Smart Portfolio Intelligence
Strategy x402 is an autonomous agent that monitors multi-chain environments to rebalance your portfolio into safe yield opportunities.
• Your Business, On-chain.
Accept payments globally. Settle instantly. Freed lets you create a storefront in seconds. Issue invoices and settle instantly in USDC or USDT directly to your wallet.
• Optimize Your Capital
Idle capital loses opportunity. Freed's Autonomous Vaults automatically route your capital to safe, yield-optimized pools so your net worth grows with every block.
Freed abstracts away blockchain complexity, so users can focus on what matters, with everything they need and nothing they don’t.
FEATURES
• Spend Yield, Keep Crypto
The card that lets you fund purchases with your portfolio growth. Never sell your principal asset unnecessarily.
• Aggregated Liquidity
Retail swaps are often inefficient. Freed aggregates liquidity from top DEXs to give you optimized pricing on every trade.
• The Financial Social Network
Money is social. Freed turns your contact list into a decentralized payment network. Send USD, EUR, or ETH as easily as a DM.
• Smart Portfolio Intelligence
Strategy x402 is an autonomous agent that monitors multi-chain environments to rebalance your portfolio into safe yield opportunities.
• Your Business, On-chain.
Accept payments globally. Settle instantly. Freed lets you create a storefront in seconds. Issue invoices and settle instantly in USDC or USDT directly to your wallet.
• Optimize Your Capital
Idle capital loses opportunity. Freed's Autonomous Vaults automatically route your capital to safe, yield-optimized pools so your net worth grows with every block.
Bitcoin Lottery
https://btclottery.ioThe Bitcoin Lottery Protocol has been my biggest hobby and self-imposed "impossible" challenge for the past 9+ years to launch a completely trustless lottery protocol + custom random generators. Initially, I set out to build unstoppable randomizing distribution raffle games on top of Bitcoin. I learned the hard way that Bitcoin smart contracts were not Turing-complete and did not support a lot of programming features.
In 2016, I ended up building a centralized version due to my lack of understanding, and the original centralized version, which I didn't like, was never made public. Bitcoin was $250 at that time. As years passed, new blockchain technologies constantly rechallenged me to rethink and rebuild. I joined the sidechain hype in the early days of 2017 and set out to improve speed and eliminate costs for permissionless environments. These environments couldn't be spammed and could be feeless while always allowing creators to create their own token distribution mechanisms that automatically rewarded their userbases with the help of Chainlink VRF and Chainlink Keepers. The old free-to-play versions used Loom Network DPOS Blockchain until 2020, when they decided to change course, which taught me 3rd-party resiliency.
In 2016, I ended up building a centralized version due to my lack of understanding, and the original centralized version, which I didn't like, was never made public. Bitcoin was $250 at that time. As years passed, new blockchain technologies constantly rechallenged me to rethink and rebuild. I joined the sidechain hype in the early days of 2017 and set out to improve speed and eliminate costs for permissionless environments. These environments couldn't be spammed and could be feeless while always allowing creators to create their own token distribution mechanisms that automatically rewarded their userbases with the help of Chainlink VRF and Chainlink Keepers. The old free-to-play versions used Loom Network DPOS Blockchain until 2020, when they decided to change course, which taught me 3rd-party resiliency.
World Liberty Financial
Maximize your crypto holdings by earning interest through various decentralized finance protocols. Need liquidity? Borrow against your crypto assets with ease and flexibility. World Liberty Financial - The Only Crypto DeFi Platform supported by Donald J. Trump!
Randomizer Network
The Randomizer Network is a novel deflationary Launchpad Protocol backed by Chainlink Verifiable Random Function (VRF) and Chainlink Keepers to ensure that all the Meta Pass Holders automatically participate in the daily deflationary no loss lottery.
Store Payment Processor
Built a self-custodial payment processor that clients and merchants can use in a wallet-to-wallet fashion. Clients can switch between client and merchant mode and create their invoices, share them, and get paid directly in their wallets using cryptocurrencies on Ethereum and Polygon Network.
Joystick Gaming
https://joystickgaming.io/Joystick is bridging the gap between Web2 and Web3 where people can earn money in the video game industry by playing games, streaming, and creating content.
I did a security audit and discovered a critical vulnerability and helped save and migrate their existing liquidity that was vulnerable and went unnoticed by multiple top auditors. Additionally, I rewrote the Joy Token and xJoy Token, added on-chain MEV protection, created the Presale contract with a live AMM OTC sale which sends xJoy to the user, and created a Claim Page using React + Next.js + Typescript in which users could see all their calculations for the 8 months cliff + 3 years linear vesting releases of the OTC.
Finally, I helped their team become better and more efficient by learning how to fork Ethereum Mainnet.
I did a security audit and discovered a critical vulnerability and helped save and migrate their existing liquidity that was vulnerable and went unnoticed by multiple top auditors. Additionally, I rewrote the Joy Token and xJoy Token, added on-chain MEV protection, created the Presale contract with a live AMM OTC sale which sends xJoy to the user, and created a Claim Page using React + Next.js + Typescript in which users could see all their calculations for the 8 months cliff + 3 years linear vesting releases of the OTC.
Finally, I helped their team become better and more efficient by learning how to fork Ethereum Mainnet.
Dough Finance
Dough Finance decentralised application is a cutting-edge DeFi non-custodial platform that revolutionizes collateral management with its innovative flash loan feature. This unique functionality enables users to triple their collateral in a single transaction by leveraging the money multiplier effect through a looping mechanism. By streamlining the process of over-collateralization, Dough Finance empowers users to optimize their financial strategies with unprecedented efficiency and flexibility.
Education
2016 - 2019
Bachelor's Degree in Economics
Universitatea Tomis - Constanta, Romania
2014 - 2016
Bachelor's Degree in Computer Science
Universitatea Ovidiu - Constanța, Romania
Skills
Libraries/APIs
React, Node.js, Web3.js, JSON-RPC, REST APIs, API Development, Vue, AirDrop, Plaid API, Crypto++, Common Crypto, OpenZeppelin, Stripe, Protobuf, Web3.py, Binance API
Tools
MetaMask, GitHub, VPN, Jira, Etherscan, VirtualBox, Remix IDE, Plaid, Ethereum Plasma, Terraform, Prisma, Slack, Google Workspace, Zapier, Claude, Claude Code, VMware, Oracle Configure, Price and Quote (CPQ) Cloud, Sequelize, Geth (go-ethereum), Drift
Languages
Solidity, Go, JavaScript, HTML, CSS, TypeScript, Python, Fantom, SQL, GraphQL, HTML5, SCSS, Rust, C++, Solidity Assembly, PHP, Objective-C, C, Assembly, Java
Frameworks
Next.js, Hardhat, Express.js, Tailwind CSS, Truffle, gRPC, Anchor, NestJS, Redux, Jest, Cosmos SDK
Paradigms
DevOps, API Architecture, Microservices, Fuzz Testing, Microservices Architecture, Distributed Computing, Agile Software Development, Application Architecture, Continuous Integration (CI), Concurrent Programming, Event-driven Architecture, Model Context Protocol (MCP), Role-based Access Control (RBAC), Automation, Scrum, Agile, Agile Project Management, Interoperability
Platforms
Blockchain, Ethereum, Chainlink, Blockchain Platforms, Decentralized Exchanges (DEXs), Amazon Web Services (AWS), Twilio, DigitalOcean, Oracle, MultiChain, Kubernetes, Linux, KVM, Bybit, Docker, Google Cloud Platform (GCP), Mapbox, Azure, Amazon EC2, Vertex AI, Robinhood, Vercel, Netlify, Avalanche, Mobile, Red Hat Linux, iOS, WordPress
Industry Expertise
Project Management, Cybersecurity, Binance Cryptocurrency Exchange, Trading Strategy Development, Banking & Finance, High-frequency Trading (HFT)
Storage
NoSQL, Databases, PostgreSQL, Redis, JSON, Data Pipelines, MongoDB, MySQL
Other
BNB Smart Chain, Tokenomics, Quality Assurance (QA), Non-fungible Tokens (NFT), Payment APIs, APIs, Cryptocurrency, ICO, ERC677, Smart Contracts, Ethereum Smart Contracts, ERC-721, Decentralized Applications, Fintech, Decentralized Finance (DeFi), Cryptocurrency Wallets, Blockchain & Cryptocurrency, Ethers.js, Blockchain Design, Decentralized Autonomous Organizations (DAO), DApps, Full-stack, Security, Architecture, ERC-1155, Audits, Team Leadership, Infrastructure, IT Infrastructure, Crypto, Software, Decentralization, Flash Loans, Integration, API Integration, Trading, Decentralized Systems, Software Architecture, Consensus Mechanism, Tokenization, QA Automation, QA Leadership, QA Testing, Manual QA, Utility Tokens, Technical Leadership, Technical Requirements, Estimations, Web 3.0, ERC-20, RPC, WebSockets, P2P, Advisory, Project Consultancy, Networks, Web Development, Algorithms, Software Engineering, Front-end, Webhooks, Stock Exchange, CTO, Leadership, Digital Asset Management, Exchanges, Fractionalization, Cryptocurrency Exchanges, Admin Panels, Back-end Development, Blockchain as a Service, Parsers, Compilers, Web3, Casinos & Gaming, Gambling, Public Finance, Back-end, Product Growth, Foundry, Web Scraping, Push Notifications, Token Design, Data Queries, Ledgers, Off-chain Development, Troubleshooting, Auditing, ÐApp, Marketplaces, CI/CD Pipelines, Scripting, Ethereum Virtual Machine (EVM), Full-stack Development, Applied Cryptography, Test Scripting, token airdrop, Distributed Ledger Technology (DLT), White Papers, Computer Science, Cryptography, Technical Writing, Apps, Quantitative Finance, Front-end Development, User Interface (UI), User Experience (UX), UTXO, Cryptocurrency APIs, Data Science, Blockchain Architecture, Mathematics, Large-scale Distributed Systems, Distributed Software, Vendor Management, Algorithmic Trading, Uniswap, Uniswap V2, Uniswap SDK, Trading Bots, Liquidity Pools, cross chain, Swaps, Aggregators, Binance Smart Chain (BSC), Automated Market Makers (AMM), Subgraph, Base Blockchain, Payment Gateways, Payment Processing, QR Codes, Cryptocurrency Trading, Maximal extractable value (MEV), Documentation, WalletConnect, MEV bots, Maximal Extractable Value (MEV), Lending, Real Estate, Project Budget Management, Project Discovery, NFT Design, Website Integration, Squarespace, Digital Payments, Payment Systems, Payment Solutions, Solana, Solution Architecture, Blockchain Development, Artificial Intelligence (AI), Credit Card Processing, Credit Cards, High-risk Credit Card Processing, PCI DSS, TradingView, Permit2, Code Review, Product Owner, System Architecture, Cloud, Deployment, Platform Engineering, Telegram Bots, AWS Cloud Operations, Performance Optimization, Real-time Data, Hyperliquid, Backtesting, Data Handling, CSV File Processing, Backtesting Trading Strategies, Data Vaults, Health, Identity & Access Management (IAM), Compliance, Google Drive, Email Automation, Card Payments, CRM Systems, SMS Bots, Airtable, Enterprise Architecture, AI Integration, Large Language Models (LLMs), OpenAI, Stablecoins, Metrics, Data Analysis, A/B Testing, Startups, Minimum Viable Product (MVP), Escrow, Hash, Deterministic Encryption, VRF, ERC-8004, Payments, Fractional CTO, Prompt Engineering, LLM Integration, AI Agent Orchestration, AI Agents, Agentic AI, Gemini, Virtual Machines, Networking, Virtual Environments, Unix/Linux Virtualization, Memory Management, Virtualization, AI Security, Data Security, Web Security, App Infrastructure, Cloud Infrastructure, Enterprise Infrastructure, Infrastructure Monitoring, Infrastructure Automation, Immutable Infrastructure, Infrastructure Security, Network Security, Customer Identity and Access Management (CIAM), Capital Markets, Venture Capital, External Audits, Audit Testing, Website Audits, IT Audits, Code Auditing, SEO Audits, Apple Pay, Google Pay, Industrial Automation Communication Protocols, Application State Management, Responsive UI, Zustand, Blockchain Wallets, Monitoring, Transactions, Open-source LLMs, Risk & Compliance.Auditing, Controllership/Accounting.External Financial Reporting, Industry.Finance.Financial Modeling.Financial Statements, Advisory.Business Advisory.Valuation, Tests of Controls, Technical Accounting, SOX Compliance, SOX, Economics, Finance, Bitcoin, Websites, Games, IT Security, IPFS, Blockchain Game Development, Distributed Systems, Team Management, Scrum Master, Polygon, Memory Pools, Bots, Healthcare Services, WebAssembly (Wasm), Biomedical Skills, Chrome Extensions, Arbitrum, Content Writing, Writing & Editing, Huff, Arweave, Filecoin, Quantitative Risk Modeling, Prediction Markets, Sidechains, Design, Universal Wallet, Blocknative, Arbitrage, Lottery, Security Audits, GRAPH, iOS Games, Smart Contract Auditing, Quantum Computing, Open Banking
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