Urban Andrej — Blockchain Developer, Rust & Solidity Specialist

Expertise in Smart Contract (8.0 yr.), Blockchain and Cryptography (8.0 yr.).

Last verified on August, 2025

Core Skills

Bio Summary

Software engineer with a Bachelor’s in Computer Science and 8 years of experience specializes in blockchain development, smart contracts, and DApps, mainly in Solidity and Rust. Demonstrated expertise in Ethereum and Solana ecosystems with significant projects such as a fully-featured NFT marketplace and the first multichain swap protocol. Excelled in developing secure, scalable solutions with 99% test coverage in Rust, contributing to the advancement of decentralized protocols. Adept in various technologies including Go, Move, Web3, DeFi, and smart contract auditing, positioning as a valuable asset for blockchain-centric roles.

Technical Skills

Programming Languages	Go, Java, Kotlin, PHP, Python, Rust, Solidity, TypeScript
JavaScript Frameworks	Angular, Express, Node.js, React
.NET Platform	Azure
Python Frameworks	Django REST framework, Flask
Android Libraries and Tools	Kotlin
PHP Frameworks	Laravel
JavaScript Libraries and Tools	React Native, Styled components
Ruby Frameworks	Ruby on Rails
Databases & Management Systems / ORM	MongoDB
UI Frameworks, Libraries, and Browsers	CSS, HTML, Material UI, Styled components
Cloud Platforms, Services & Computing	AWS, Azure
Industry Domain Experience	Blockchain
BlockChain and Decentralized Software	Anchor, Cryptography, DeFi, DEX, Hardhat, Smart Contract, Solana, Substrate, Truffle
SDK / API and Integrations	API, GraphQL
Deployment, CI/CD & Administration	CI/CD
QA, Test Automation, Security	Cypress, Jest, Mocha
Virtualization, Containers and Orchestration	Docker, Kubernetes
Methodologies, Paradigms and Patterns	FDD
UI/UX/Wireframing	Figma
Version Control	Git
Mail / Network Protocols / Data transfer	HAProxy
Web/App Servers, Middleware	Nginx

Work Experience

Senior Blockchain Developer, NFT Marketplace and Test-net App Chain

Duration: Jun 2023 - Mar 2025

Summary:

Developed and maintained a fully-featured NFT marketplace using Rust within the Substrate framework
Conducted smart contract audits and mentored junior engineers

Responsibilities: NFT functionality development, smart contract audits, mentoring

Technologies: Rust, Substrate

Smart Contract Engineer, Smart Contract Engineering and Protocol Optimization

Duration: Oct 2022 - May 2023

Summary: Deployed Rust-based smart contracts for decentralized applications, led Solana protocol optimization, and promoted secure data ownership for Koii Network.

Responsibilities: Smart contract development and deployment, decentralized protocol optimization, team collaboration

Technologies: Rust, Solana, Decentralized Protocols, Cryptography, Web3

Blockchain Developer, Multichain Swap Protocol

Duration: Aug 2021 - Jun 2022

Summary: Pioneered the first multichain swap protocol on Layer Zero and executed core smart contract implementations for secure cross-chain interactions.

Responsibilities: Smart contract implementation, multichain swap protocol development, security testing

Technologies: Solidity, Ethereum, Solana, Layer Zero Protocol

Blockchain Developer, Enjin Wallet 2.0 & NFT.io Marketplace

Duration: May 2020 - Jul 2021

Summary:

Implemented EIP-1559 and various cryptocurrency support using Solidity and Rust in Enjin Wallet 2.0 development, contributed to NFT marketplace development

Responsibilities: Cryptocurrency system upgrades, blockchain infrastructure development, NFT marketplace contribution

Technologies: Solidity, Rust, EIP-1559, BEP-20, Substrate-SDK

Full Stack Engineer, Web Platform and API Development

Duration: May 2019 - May 2020

Summary: Led the development of Cape & Bay's primary web platform and APIs while maintaining database integrity and addressing system issues.

Responsibilities: Web platform design and implementation, database management, API development

Technologies: Node.js, Python, Django, Flask, React, GraphQL

Full Stack Developer, Pharmacy Store and Healthcare App

Duration: Apr 2018 - May 2019

Summary: Built a custom PHP framework for a pharmacy store app and contributed to the development and launch of a responsive website and storybook.

Responsibilities: Custom PHP framework development, RESTful API and GraphQL implementation, website launch

Technologies: PHP, Node, NGINX, HA Proxy, React, Vue.js

Education

Saint Louis University
Bachelor of Computer Science GPA: 3.8 / 4.0
2013 - 2017

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