Portfolio - Julien Halde | Blockchain Developer

The first decade of blockchain was about proving the concept, the next will be about proving real utility at scale.

About me

I'm Julien

Blockchain developer obsessed with designing innovative DeFi solutions and building smart contract architectures that scale. Currently pursuing Computer Science at Concordia University while shipping production-ready Web3 applications.

Based in Montreal, I'm a 20-year-old developer specialized in Ethereum, React frontends, and mobile apps. Hackathon winner and founder of GeniePay, I bridge the gap between complex blockchain technology and intuitive user experiences.

Building the Web3 revolution, one block at a time

Professional Experience

ChargeHub

Software Developer

Winter 2025 - Summer 2025

Participated in mobile integration for one of North America's largest EV charging networks with 350K+ users
Built Android features using Kotlin (Jetpack Compose) and iOS features with Swift (UIKit & SwiftUI)
Reverse-engineered Android SDKs to identify and document critical security vulnerabilities
Improved the bug-reporting system, completely eliminating empty user submissions
Managed app releases on Google Play Store including versioning and release cycles

Ethereum Foundation

Blockchain Translator

Summer 2025

Translated 4,000+ words of Ethereum documentation into French
Contributed to developer tooling improvements and documentation standards

CAVIP Swimming Club

Lead Swimming Coach & Operations Manager

Summer 2023

Managed team of 15 coaches and 120+ competitive swimmers with $30K seasonal budget
Organized regional-level competitions with 500+ participants
Led the club to a 20% increase in membership