- Led the development and enhancement of complex sharing functionality, including Figma design integration, image quality improvements, and feature synchronization across frontend and backend systems.- Investigated and resolved critical net query parameter state bugs and optimized SQL requests for backend efficiency, including bug fixes related to infinite signature signing, login functionality, and leaderboard optimizations.- Spearheaded request limiting implementation, collaborated on DOS attack prevention strategies, and improved system scalability through infrastructure onboarding and backend optimization.- Architected and implemented node switching functionality, including backend logic for node switching PRs and production deployment preparation.- Designed and optimized a robust public API with schema updates, endpoint filtering, and integration with the stat service, ensuring API performance through query optimization and error resolution.- Led the end-to-end development of multisend features, including smart contract interaction, backend deposit and withdrawal logic, referral system integration, and frontend support for multisend transactions.- Managed blockchain integrations, including Mantle gas changes, Linea attestation parsing, and support for various networks such as Ethereum, Arbitrum, and zkSync.- Delivered frontend features such as ETH/USD balance toggling, scroll badge functionality, and multisend UI enhancements, ensuring seamless integration between frontend and backend services.- Optimized backend infrastructure by resolving high CPU load issues.- Conducted thorough testing and debugging of public API services, smart contracts, and database interactions to ensure system stability.- Collaborated with cross-functional teams on feature discussions, multisend logic, and rank optimization, continuously refining backend and frontend processes to improve user experience.

- Implemented Token ERC-20 for Binance Smart Chain network using Openzeppelin's ERC-20 standartcontract;- Implemented Presale Contract for mentioned above token- Added Openzeppelin's security contracts to improve presale contract's security and decrease risk ofvulnerabilities- Created affiliate system to make users being awarded if they invite someone to take participation in thepresale- Integrated Chainlink's price data feed contracts for correct calculation of token price- Automated unit and integration tests using Hardhat, Mocha, and Chai to cover the whole logic ofcontracts and interaction with them- Implemented scalable deployment hardhat tasks to deploy contracts to test- and main networks usingHardhat- Developed private network using Ganache-CLI and deployed contract to a private network to avoidproblems connected with test networks- Applied tenderly.co debugging feature to detect problems of failed transactions- Implemented preact widget application which build integrates with Wordpress website- Implemented real-time data update and validation using wagmi-hooks- Integrated Rainbow kit to give user option to select their most favourite wallet- Implemented internalization using i18n

- Implemented contracts with OpenZeppelin libraries to follow the best solutions- Integrated Fireblocks solution to make user have an ability to use custodial wallet- Refactored and added improvements to the ERC-721 NFT contract to fix security problems and knownbugs- Automated unit and integration tests using Hardhat, Mocha, and Chai to cover the whole logic ofcontracts and interaction with them- Supported the integration of contracts' methods using Web3.js to both back- and front-end sides- Implemented scalable deployment hardhat tasks to deploy contracts to test- and main networks usingHardhat- Developed private network using Ganache-CLI and deployed contract to a private network to avoid- problems connected with test networks- Integrated PancakeSwapV2 contracts to get actual prices of BNB dependent on Pancake's LPs- Applied tenderly.co debugging feature to detect problems of failed transactions- Integrated Chainlink VRF Randomness into smart-contract to get an ability of getting random value forgambling solution- Implemented contracts which are upgradable using Solidity Openzeppelin's Upgrades- Developed AWS lambda function to aggregate data from blockchain and add it to google spreadsheet- Applied Openzeppelin's Clones pattern in smart-contracts to reduce cost of deployment of newcontractsNDA - CryptoCoin- Implemented coin's smart-contract using Openzeppelin's ERC-20 pattern- Developed Presale smart-contract with Openzeppelin library to follow best practices- Analyzed and refactored smart-contracts to avoid security issues using Mythril- Covered smart-contracts with tests using Mocha and Chai- Implemented scalable deployment hardhat tasks to deploy contracts to test- and main networks usingHardhat- Integrated Chainlink's Data Feed to get latest BNB price for Presale smart-contract