Mobile application developer (Android & Flutter) with 15 years of experience, I built my expertise working with leading teams in the Paris tech ecosystem: LeBonCoin, Meetic, Molotov.tv, Happn, BeReal… I frequently support startups from early-stage to scale-up on the following missions: ► Team Reinforcement Whether it's addressing understaffing by joining a feature team or providing temporary specialized skills (interim lead developer, training, etc.), I am fully operational in: 📱 Flutter and Android development (Kotlin, coroutines, Jetpack Compose…) 📐 Architecture: Clean Architecture, MVVM, BLoC 🏭 Industrialization: Git, code reviews, testing, CI/CD 🎯 Agile methods: SCRUM, Kanban, release train 🤝 Collaboration tools: Atlassian Jira, Figma, Notion, … ► Launching a New App I can handle the development of a mobile app from initial design to production release on Google Play and the App Store. 💡 Design: user experience design, lean startup 📐 Architecture: my area of expertise; most of my missions specifically involve setting up (or redesigning) application architecture 🏗️ Development: native apps (Kotlin / Android) or cross-platform (Flutter), as well as back-end development (microservices, lambdas, serverless… depending on the need) ➕ The added value: alternating between freelancing and entrepreneurship, I take interest in the business side beyond pure technical work; my approach is ROI-driven and focused on value creation.

Geoffrey Marizy

Mobile application developer (Android & Flutter) with 15 years of experience, I built my expertise working with leading teams in the Paris tech ecosystem: LeBonCoin, Meetic, Molotov.tv, Happn, BeReal… I frequently support startups from early-stage to scale-up on the following missions: ► Team Reinforcement Whether it's addressing understaffing by joining a feature team or providing temporary specialized skills (interim lead developer, training, etc.), I am fully operational in: 📱 Flutter and Android development (Kotlin, coroutines, Jetpack Compose…) 📐 Architecture: Clean Architecture, MVVM, BLoC 🏭 Industrialization: Git, code reviews, testing, CI/CD 🎯 Agile methods: SCRUM, Kanban, release train 🤝 Collaboration tools: Atlassian Jira, Figma, Notion, … ► Launching a New App I can handle the development of a mobile app from initial design to production release on Google Play and the App Store. 💡 Design: user experience design, lean startup 📐 Architecture: my area of expertise; most of my missions specifically involve setting up (or redesigning) application architecture 🏗️ Development: native apps (Kotlin / Android) or cross-platform (Flutter), as well as back-end development (microservices, lambdas, serverless… depending on the need) ➕ The added value: alternating between freelancing and entrepreneurship, I take interest in the business side beyond pure technical work; my approach is ROI-driven and focused on value creation.

Available to hire

Mobile application developer (Android & Flutter) with 15 years of experience, I built my expertise working with leading teams in the Paris tech ecosystem: LeBonCoin, Meetic, Molotov.tv, Happn, BeReal…

I frequently support startups from early-stage to scale-up on the following missions:

► Team Reinforcement

Whether it’s addressing understaffing by joining a feature team or providing temporary specialized skills (interim lead developer, training, etc.), I am fully operational in:

📱 Flutter and Android development (Kotlin, coroutines, Jetpack Compose…)

📐 Architecture: Clean Architecture, MVVM, BLoC

🏭 Industrialization: Git, code reviews, testing, CI/CD

🎯 Agile methods: SCRUM, Kanban, release train

🤝 Collaboration tools: Atlassian Jira, Figma, Notion, …

► Launching a New App

I can handle the development of a mobile app from initial design to production release on Google Play and the App Store.

💡 Design: user experience design, lean startup

📐 Architecture: my area of expertise; most of my missions specifically involve setting up (or redesigning) application architecture

🏗️ Development: native apps (Kotlin / Android) or cross-platform (Flutter), as well as back-end development (microservices, lambdas, serverless… depending on the need)

➕ The added value: alternating between freelancing and entrepreneurship, I take interest in the business side beyond pure technical work; my approach is ROI-driven and focused on value creation.

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Language

French
Fluent
English
Advanced
German
Beginner

Work Experience

Flutter Developer at Hush
September 30, 2025 - September 30, 2025
Re-architecting the application to improve delivery capacity, after organic growth of the codebase made changes complex and costly.
Chief Technology Officer at Strangrs
January 31, 2025 - January 31, 2025
Rewrote POC into a scalable, maintainable app. Leveraged Flutter across mobile and web—including the back-office—to maximize code reuse and accelerate development.
Chief Technology Officer at Mojito.party
March 31, 2024 - March 31, 2024
Developed a social network from scratch, from design and UX to stores deployment. Flutter front-end; Firebase and lambdas for the back-end.
Android Developer at Leboncoin.fr
March 31, 2022 - March 31, 2022
LeBonCoin turned to me after two failed internal attempts to successfully refactor a core part of the app. Also laid the foundation for integration testing.
Android Developer at BeReal.
October 31, 2021 - October 31, 2021
Led the rewrite of the Android app with an architecture tailored to business needs, using Clean Architecture principles and modern tech such as Jetpack Compose and Coroutines.
Android Developer at Meetic
June 30, 2021 - June 30, 2021
Originally brought in for Android development, I volunteered to support the struggling back-end team by taking ownership of one of the microservices, while still fulfilling my initial role.
Android Developer at MédecinDirect
January 31, 2021 - January 31, 2021
Laid the foundations of the Android app and industrialized the development process, leading to a twofold increase in team productivity.
Lead Developer at Molotov
May 31, 2020 - May 31, 2020
Acted as interim lead for a team of 6 Android developers. Led a full re-architecture of the app: modularization, Clean Archi, unit tests, and reactive programming.
Android Developer at happn
December 31, 2019 - December 31, 2019
Reinforced the team with an outside perspective during the app rewrite. Also provided knowledge transfer (Kotlin, RxJava, etc.) through pair programming, technical presentations, and internal tech talks.

Education

Master of Science, IT at Institut supérieur d'Electronique de Paris
January 1, 2004 - January 1, 2010
IT at Inha University
January 1, 2009 - January 1, 2009

Qualifications

Add your qualifications or awards here.

Industry Experience

Software & Internet, Professional Services

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