Andres Felipe Velasquez Trujillo — Blockchain & Full Stack Engineer

Expertise in Blockchain and Cryptography (4.0 yr.), Smart Contract (3.0 yr.).

Last verified on May, 2026

Core Skills

Bio Summary

Blockchain & Full Stack Engineer with 4+ years of experience developing DeFi systems, smart contracts, and scalable Web3 infrastructure using Solidity, Foundry, Hardhat, and Ethereum.
Proficient in frontend and backend technologies including React, React Native, Node.js, Ruby on Rails, TypeScript, and PostgreSQL, integrated fintech and decentralized applications.
Expertise in smart contract security, testing methodologies (fuzz, invariant, stateful), and security tools like Slither and Aderyn, ensuring robust and secure protocol development.
Hands-on experience building governance systems, treasury management, NFT platforms, and payment integrations with financial APIs and blockchain wallets.

Technical Skills

Programming Languages	JavaScript, Solidity, TypeScript
JavaScript Libraries and Tools	Ethers.js, React Native, Redux-Saga, Web3.js
JavaScript Frameworks	Express, Ext JS, React
Ruby Frameworks	Ruby on Rails
Databases & Management Systems / ORM	PostgreSQL
UI Frameworks, Libraries, and Browsers	Material UI, Tailwind CSS
Blockchain and Decentralized Software	Brownie, Chai, DeFi, ERC-20, ERC-721, Ethers.js, Foundry, Hardhat, MetaMask, OpenZeppelin, RainbowKit, Smart Contract, Truffle
QA, Test Automation, Security	Mocha, Unit Testing, Usability tests
SDK / API and Integrations	RESTful API
Other Technical Skills	Financial Services, InterPlanetary File System, Slither, Viem, WAGMI

Work Experience

Blockchain Engineer - Investment Armendariz (DeFi Infrastructure for Governance and Treasury Management)

Duration: Aug 2025 – Present
Summary:

Development of decentralized finance (DeFi) infrastructure focusing on governance systems, treasury management, vault architecture, and on-chain operational controls
The project aims to build secure and modular smart contract protocols to support decentralized governance and financial operations

Responsibilities:

Develop Solidity smart contracts using Foundry-based workflows and modular protocol architecture.
Implement frontend architecture using React, TypeScript, wagmi, viem, RainbowKit, and TailwindCSS.
Build comprehensive testing suites including unit tests, fuzz testing, invariant testing, and stateful testing workflows.
Perform security analysis using Slither and Aderyn, applying secure Solidity development practices and protocol optimization.

Technologies: Solidity, Foundry, React, TypeScript, wagmi, viem, RainbowKit, TailwindCSS, Slither, Aderyn

Full Stack Developer - Vita Wallet (Fintech Web and Mobile Applications)

Duration: Aug 2021 – Nov 2025
Summary:

Development of fintech web and mobile applications integrating financial APIs, banking systems, blockchain services, Binance services, and international payment providers
The project focused on building scalable payment workflows and financial platforms to enhance user experience and reliability

Responsibilities:

Developed frontend and backend features using Ruby on Rails, React, React Native, and JavaScript.
Integrated various financial APIs and blockchain services to support payment workflows.
Built testing workflows to improve platform reliability, maintainability, and stability.
Collaborated on secure financial application architecture and API integration processes.

Technologies: Ruby on Rails, React, React Native, JavaScript

Blockchain & Smart Contract Engineer (Independent Blockchain Projects)

Duration: Jul 2021 – Aug 2022
Summary:

Development of decentralized applications (dApps), NFT systems, ERC-20/ERC-721 token standards, and smart contracts
Projects included a blockchain healthcare platform with subscription systems and tokenized services, NFT minting systems, decentralized voting applications, and blockchain lottery platforms

Responsibilities:

Developed smart contracts using Solidity and implemented blockchain standards ERC-20 and ERC-721.
Built blockchain healthcare platform architecture with subscription and tokenized services.
Implemented NFT minting systems, decentralized voting applications, and blockchain lottery platforms.
Integrated MetaMask, Ethers.js, Web3.js, OpenZeppelin, IPFS, and React-based Web3 interfaces.
Worked with Hardhat, Truffle, Chai, and smart contract testing workflows focused on secure Solidity development.

Technologies: Solidity, Hardhat, Truffle, Chai, Ethers.js, Web3.js, OpenZeppelin, IPFS, React

Education

Cyfrin Updraft
Smart Contract Security & Blockchain Engineering
2024 – 2025
Universidad de Antioquia
Mathematics
2014 – 2021
Henry
Full Stack Web Development
2021
Platzi
Blockchain & Cryptocurrency School
2021 – 2022

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