Description

13+ years of experience building scalable systems including 6 years at Microsoft.

I help companies bridge the gap between complex product requirements and high-performance execution. Whether you need a full-stack overhaul or a specialist to lead a critical migration, I deliver production-ready code that scales to millions of users.

Core Expertise

- End-to-End Frontend Leadership: Building robust applications from initial concept to final product using React and TypeScript.

- Robust Backends: Expert in Node.js, and Java, with a focus on high availability and high-throughput systems.

- Cloud & DevOps: Deep experience in Azure and AWS, containerization (Docker/K8s), and CI/CD pipelines

Languages

English
Native or bilingual
French
Native or bilingual

Workplace preferences

Can work on-site

Pau (up to 50km)

CALTOPO
Senior Software Engineer / Frontend Lead
January 2021 - February 2024 (3 years and 1 month)
United States
• ● Led a full migration of the legacy mapping application to a modern React/TypeScript architecture, reducing production bugs by 35% and significantly improving maintainability and user experience.
• ● Delivered major cross-platform features on web (TS/React), iOS (Swift), and Android (Java), ensuring a consistent interface for 500,000+ monthly active users.
• ● Architected and implemented a full-stack overhaul of the billing and subscription system (React/TS + Java/Spring/Hibernate + Stripe), contributing to a 15% increase in ARPU.
• ● Improved build and deployment pipelines (GitHub CI, esbuild, Gradle), reducing deployment times from 3 minutes to 20 seconds (-89%) and boosting developer productivity across a 10+ engineer team.
• ● Mentored junior developers on backend and mobile development best practices, conducting code reviews and pair programming sessions to raise engineering quality.
• ● Improved onboarding processes by documenting internal APIs, SDK behaviors, and dev workflows, reducing new engineer ramp-up time.
Stripe Typescript Java React.js CI/CD Management
MICROSOFT - AppCenter
Senior Software Engineer
September 2017 - September 2020 (3 years)
Seattle, WA, USA
• ● Built core areas of the AppCenter web frontend (Analytics, Settings, Push) using TypeScript, React, MobX, and Webpack for a platform serving 1M+ developers.
• ● Contributed to a highly scalable push delivery system within Azure Notification Hub (C#, Kubernetes, Docker), supporting billions of push notifications monthly.
• ● Improved and maintained critical Node.js REST APIs, achieving 99.99% uptime through enhanced reliability and performance tuning.
Node.js React.js C# Docker Typescript
MICROSOFT - Azure Mobile Engagement
Senior Software Engineer
September 2014 - August 2017 (2 years and 11 months)
Seattle, WA, USA
• ● Led the migration of the Capptain platform to Microsoft Azure standards, completing the porting of 3 core services in under 9 months.
• ● Migrated the internal message broker from RabbitMQ to Azure EventHub (Java), reaching throughput of 50,000 events/sec with improved reliability.
• ● Executed a complex MySQL → Azure SQL database migration with zero customer downtime, ensuring data integrity at scale.
Java MySQL Microsoft Azure RabbitMQ iOS

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Engineering Degree (MSc)
INSA
2008
Engineering Degree (MSc)
Degree in Technology (BSc)
IUT
2005
Degree in Technology (BSc)

Fabien Le Gallo

Senior Full-Stack Engineer

About Fabien

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