Julian Cislo
Verified Expert in Engineering
Blockchain Developer
Oshawa, Canada
Toptal member since October 6, 2022
Julian is a full-stack Web 3.0 developer and consultant. He specializes in solidity smart contracts design, development, and security considerations. He has founded QuantDeFi, a consulting company in the blockchain space that offers to solve all Web 3.0-related problems for clients looking to integrate blockchain solutions. Julian also features his skills in transaction automation, having constructed arbitrage and liquidation bots utilizing flash-loan technologies.
Portfolio
Experience
- Blockchain - 10 years
- Web3.js - 6 years
- Smart Contracts - 6 years
- ERC-1155 - 5 years
- ERC-721 - 5 years
- Solidity - 5 years
- ERC-20 - 5 years
- Full-stack Development - 3 years
Availability
Preferred Environment
Windows, Ubuntu, MacOS, TypeScript, Solidity, Truffle, Hardhat, NPM, JavaScript, Non-fungible Tokens (NFT), Blockchain, MetaMask
The most amazing...
...protocol I've built is a P2P NFT lending service with tradeable NFT derivatives.
Work Experience
CEO
QuantDEFI consulting
- Developed full-stack blockchain applications for various projects.
- Created bot systems for blockchain transaction automation, including trading bots, arbitrage, and liquidations.
- Audited smart contract code for various clients, seeking common and uncommon potential security exploits and gas optimizations.
Web3.js Engineer
UE Games
- Developed and deployed NFT solutions to be distributed to hundreds of gamers.
- Designed and implemented tokenomics systems for various fungible tokens.
- Consulted and advised about several scaling options, including Polygon and ImmutableX, to improve transaction speeds and costs.
Trading Bot Developer
Freelance Client
- Developed on-chain trading business logic and implemented it into a Node.js back end paired with a MySQL database.
- Created API and WebSocket endpoints for live data feeds and direct connection to the front end.
- Expanded the system for commercial use, enabling multiple users to access it simultaneously.
- Utilized various decentralized finance liquidity pool protocols such as Uniswap.
Senior Full-stack Developer
PAWNSPACE
- Created the peer-to-peer NFT collateralization protocol.
- Integrated advanced Solidity concepts, including in-line assembly and upgradable contracts.
- Managed a small team of developers to create promotional NFTs and minting UI.
Smart Contract Engineer
Freelance Client
- Developed an experimental stablecoin backed by liquidity pool tokens, including uniswap and balancer.
- Utilized Chainlink Oracle feeds for the valuation of liquidity tokens and to determine stablecoin issuance.
- Anticipated achieving a stablecoin without needing a liquidation mechanism.
- Faced the challenge of ensuring the peg remained in cases of extreme divergence loss.
Experience
Lotto Balls
The game's goal is to select eight digits from 1 to 8 each and then attempt to match them with a randomly generated set. The more digits match, the greater the prize. The protocol also contains a native fungible token that is minted as a prize and enables an alternative way to play the game. The game is live on Polygon and requires MetaMask pointed at the polygon network to access the application.
Arbitrage, Liquidation, and Other Miscellaneous Transaction Automation Tools
Some bots, such as single-protocol arbitrage or NFT-game automation, are simple because they only require a monitoring script and direct interaction with existing protocols. In other cases, like multi-protocol arbitrage and liquidations, I have written custom smart contracts to combine multiple on-chain actions into single transactions. Common design patterns include using flash loans or flash-like designs to integrate various function calls into a single atomic action. For most automation tasks, fast and reliable access to a node is necessary; therefore, I opt to run my blockchain nodes locally to bypass public RPC rate limits.
I have experience operating nodes on Ethereum, Avalanche, Harmony, Polygon, Optimism, Binance Smart Chain, and Fantom.
Rentable
https://github.com/Rentable-EthToronto/rentable-contractsCaesar's Temple
Education
Bachelor of Science in Physics
University of Guelph - Guelph, Ontario, Canada
Certifications
Blockchain Development
George Brown College
Skills
Libraries/APIs
Web3.js, React, Node.js, Binance API
Tools
NPM, MetaMask, Git, Ganache, Ganache CLI
Languages
TypeScript, Solidity, JavaScript, Python, HTML, CSS, SQL, Python 3, Java, C++
Frameworks
Truffle, Hardhat
Platforms
Windows, Blockchain, Ethereum, Oracle, Blockchain Platforms, Decentralized Exchanges (DEXs), Ubuntu, MacOS, Hyperledger, X (formerly Twitter)
Industry Expertise
Project Management
Storage
JSON
Paradigms
Management
Other
Complex Problem Solving, Creative Problem Solving, Ethereum Smart Contracts, Smart Contracts, Cryptocurrency, Bots, Decentralized Finance (DeFi), Crypto, Lending, Security, Non-fungible Tokens (NFT), Uniswap, Arbitrage, Blockchain & Cryptocurrency, Full-stack, Tokenomics, ERC-721, ERC-1155, ERC-20, APIs, Utility Tokens, Polygon, Web3, Token Design, Tokenization, Ethereum Virtual Machine (EVM), Base Blockchain, Cryptocurrency Wallets, Decentralized Applications, Full-stack Development, Software Architecture, Trading, Solana, Foundry, Writing & Editing, Web Development, Web Marketing, User Experience (UX), Physics, Mathematics, Computer Science, Education, Training
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