About Oh BiBi

Oh BiBi is an independent mobile game studio of 80 people based in Paris, dedicated to creating bold, innovative, and high-quality gaming experiences. We are the creators of FRAG Pro Shooter, a worldwide hit with hundreds of millions of players, Ratchet & Clank: Ranger Rumble, and BEAST, which won the Pégases Award for Best Mobile Game in 2025.

We are currently working with Rovio on the next Angry Birds game, a fourth-generation luck-battle blending runner gameplay with the deep and efficient meta of luck-battle games !

About the Role

You turn ideas into solid systems.

You love breaking complex problems down into numbers, rules and logic, then turning them into playable experiences. You think in models, probabilities and feedback loops, and you are fluent in mathematics (bonus if you like to dive into code to make ideas real).

As a System Designer, you will work closely with the game lead, game designers, data analysts. Your role will be to design, model and optimize in-game systems that shape the full player experience: core loops, economy, progression, monetization, scoring, events and LiveOps.

If you're looking for a role at the crossroads of game design, mathematics and engineering and you like turning reality into equations and equations into fun, we want to hear from you.

Core Responsibilities

• Design, model and iterate on core game systems, from early concepts to live operations

• Translate abstract design intentions into clear mathematical models, rulesets and scalable systems

• Build and balance in-game economies, progression systems, monetization mechanics and reward structures

• Define and optimize core loops, scoring systems, events and LiveOps features to drive player engagement and retention

• Collaborate closely with Game Designers to ensure systems support gameplay vision and player experience

• Work with Data Analysts to define KPIs, analyze player behavior, and make data-driven decisions

• Prototype systems using tools, spreadsheets or code to validate assumptions and balance

• Contribute to system implementation, ideally in Unity using C#, or by closely supporting the gameplay programmers

• Identify risks, edge cases and exploits within systems, and proactively propose solutions

• Iterate continuously based on playtests, live data and business objectives

What are we looking for?

• A System Designer with a strong focus on execution

• Strong ability to transform abstract problems into concrete mathematical models, rules and systems

• Comfortable working across multiple systems: game design, difficulty, scoring, economy, monetization and LiveOps

• Analytical and solution-oriented mindset, able to break down complex problems and turn them into actionable systems

• A background in game development, data, programming or system-heavy game design

• Experience in mobile games and systemic games is a strong plus

• Ability to collaborate closely with Game Designers, Data Analysts, and Product teams without taking ownership of core gameplay direction

• Data-driven approach, with the ability to reason using metrics and player behavior

• High level of motivation, focus and willingness to iterate

• Ability to prototype systems using spreadsheets, tools or code

• Nice to have: ability to implement or prototype systems in Unity using C#

• Fluent in French

On-site presence

• Collaboration matters to us! We meet in our Paris office twice a week (Tuesdays and Thursdays)