Andres Felipe Velasquez Trujillo — Blockchain & Full Stack Engineer

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

Last verified on May, 2026

Core Skills

Bio Summary

Blockchain & Full Stack Engineer with 7+ years of experience specializing in Solidity smart contract development, DeFi infrastructure, and scalable Web3 applications using Foundry, Hardhat, and OpenZeppelin.
Proficient in frontend and backend technologies including React, React Native, TypeScript, Node.js, Ruby on Rails, and PostgreSQL, secure fintech and decentralized platforms.
Expertise in smart contract security analysis and testing methodologies such as fuzz testing, invariant testing, and static analysis tools like Slither and Aderyn.
Strong foundation in mathematics and computer science, supported by formal education and continuous blockchain security training.

Technical Skills

Programming Languages	JavaScript, Python, 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, Ethers.js, Foundry, Hardhat, MetaMask, OpenZeppelin, RainbowKit, Truffle, Viem, WAGMI
Methodologies, Paradigms and Patterns	FDD
QA, Test Automation, Security	Mocha, Unit Testing, Usability tests
SDK / API and Integrations	RESTful API
Other Technical Skills	Financial Services, InterPlanetary File System, Slither

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 DeFi protocols using modern Ethereum tooling

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 scalable payment workflows and financial platform features

Responsibilities:

Developed fintech web and mobile applications using Ruby on Rails, React, React Native, and JavaScript.
Integrated financial APIs, banking systems, blockchain services, Binance services, and international payment providers.
Implemented scalable backend and frontend features for payment workflows and financial platforms.
Built testing workflows improving 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 – Present
Summary:

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

Responsibilities:

Developed smart contracts using Solidity and implemented NFT minting systems and decentralized voting applications.
Built blockchain healthcare platform architecture with subscription systems and tokenized services.
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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