Full-Stack and Blockchain Developer with over 10 years of experience in delivering cutting-edge solutions that drive project success and enhance functionality. Expertise spans blockchain technology, smart contract implementation, and full-stack development, ensuring high-quality deliverables that elevate user experiences. Proficient in modern programming languages and frameworks, adept at integrating innovative technologies to streamline processes and improve operational efficiency. Committed to continuous learning and tackling new challenges within the blockchain domain, consistently aiming to contribute to impactful projects that push the boundaries of technology.
Experience: 8 years
Yearly salary: $96,000
Hourly rate: $50
Nationality: 🇷🇸 Serbia
Residency: 🇷🇸 Serbia
Experience
Freelance Blockchain Developer
Self-Employed 2024 - 2025
- Developed and deployed custom smart contracts for DeFi lending platforms, staking protocols, and NFT marketplaces, ensuring secure, gas-efficient, and scalable implementations. - Conducted rigorous unit and integration testing using Hardhat and Chai to prevent security vulnerabilities. - Built and launched a feature-rich NFT minting platform that integrates IPFS for decentralized storage, ensuring metadata immutability and long-term accessibility. - Implemented dynamic NFT metadata updates, allowing artists to modify NFT attributes post-mint based on predefined logic. - Conducted smart contract security audits, identifying and mitigating reentrancy attacks, integer overflows, and access control vulnerabilities. - Provided comprehensive audit reports with risk assessments and mitigation strategies, leading to a 40% reduction in potential exploits before deployment. - Developed and integrated multi-chain interoperability solutions, enabling seamless asset transfers between Ethereum, BNB Chain, and Polygon. - Utilized Layer 2 scaling solutions (Optimistic Rollups, zk-Rollups) to optimize transaction costs, reducing gas fees by up to 60%. - Collaborated with blockchain startups to design tokenomics strategies, creating custom vesting contracts, governance token frameworks, and automated liquidity mechanisms for DeFi protocols. - Engineered yield farming and staking smart contracts, ensuring fair reward distribution and preventing flash loan exploits.
Blockchain Developer
FREYSOFT 2019 - 2024
- Designed, developed, and audited smart contracts for DeFi platforms, NFT marketplaces, and DAOs, ensuring secure, gas-efficient, and upgradeable architectures while maintaining full EVM compatibility. - Deployed ERC-20 and ERC-721 token contracts, handling transactions exceeding $5M+ in total volume, and implemented automated liquidity pool mechanisms for a decentralized exchange (DEX). - Optimized gas costs in Solidity smart contracts by implementing bitwise operations, storage packing, and function modifiers, reducing average gas fees by 40% on Ethereum mainnet. - Integrated Chainlink oracles to enable real-time price feeds and data-driven smart contract executions, ensuring secure on-chain data verification for lending protocols. - Engineered a staking and rewards mechanism, allowing users to stake governance tokens in a decentralized voting system with APY adjustments based on network participation. - Led a team of blockchain engineers to deploy Layer 2 scaling solutions using zk-Rollups, significantly reducing congestion on Ethereum mainnet and decreasing transaction fees by up to 80%.
Senior Full Stack Developer
Sigma Software Group 2016 - 2019
- Led the end-to-end development of a high-traffic web application serving over 1M users, optimizing frontend performance with Next.js server-side rendering (SSR) and reducing page load times by 50%. - Architected and implemented a scalable microservices infrastructure, migrating from a monolithic system to containerized Node.js services on AWS ECS, which improved system reliability and reduced downtime by 40%. - Optimized PostgreSQL database queries using indexing and partitioning techniques, improving read/write efficiency by 30% and reducing query execution time from 200ms to 50ms. - Designed and developed GraphQL APIs, reducing frontend-over-fetching issues and decreasing API response times by 35%, enhancing overall user experience. - Built and maintained CI/CD pipelines using Docker, Kubernetes, and GitHub Actions, automating deployments and cutting release cycles from 2 weeks to just 3 days. - Mentored a team of 5 junior developers, conducting code reviews and workshops on React best practices, TypeScript, and backend optimizations, resulting in a 20% improvement in overall code quality.
Full Stack Developer
Accedia 2014 - 2016
- Developed a real-time chat application using WebSockets and Node.js, handling 100,000+ concurrent users with a latency of under 50ms, ensuring a seamless messaging experience. - Redesigned the entire frontend architecture with Vue.js and Vuex, improving modularity and enhancing user engagement by 20% through a more intuitive UI. - Implemented JWT-based authentication and OAuth2 login integrations (Google, Facebook), enhancing user security and reducing unauthorized access incidents by 60%. - Refactored backend services by migrating from REST APIs to GraphQL, reducing over-fetching issues and cutting API response payload size by 40%, leading to faster app performance. - Automated DevOps workflows by setting up CI/CD pipelines with Docker and AWS CodePipeline, reducing deployment time from 30 minutes to under 5 minutes. - Integrated Redis caching mechanisms for frequently accessed database queries, decreasing load on MongoDB servers and reducing response times from 800ms to 150ms.
Software Engineering Intern
InnovateTech Startup 2013 - 2014
- Collaborated with senior engineers to develop and optimize a real-time analytics dashboard, reducing data processing latency by 30% using Node.js and WebSockets. - Assisted in frontend development by building reusable React components and implementing state management with Redux, improving UI responsiveness by 25%. - Implemented RESTful APIs with Express.js and connected them to a MySQL database, optimizing query execution time through indexing and caching strategies. - Integrated third-party APIs (Google Maps, Stripe) to enhance user functionality, reducing manual user input by 40% through automation. - Developed unit tests using Jest and Mocha, increasing code coverage from 60% to 90%, leading to more stable production releases.
Skills
dapp
defi
evm
javascript
jira
nextjs
nft
node
php
python
react
rust
smart-contract
solana
tokenization
typescript
solidity