We're working with an established international iGaming business that develops online slot games across regulated markets globally.

The business is now investing in the next generation of its game-engine technology, with a focus on modernising the underlying architecture, improving mathematical validation and building a new slot game engine from the ground up.

This hire will play a key role in shaping that next engine and the technical direction of the platform.

You'll join a small specialist team alongside another Game Engine Engineer and a Game Mathematician, with significant ownership across architecture, mathematical validation and delivery.

What you'll be doing Designing and building a new slot game engine from scratch

Owning game-engine projects end to end

Working closely with mathematicians to turn mathematical models into production software

Building simulations to validate game behaviour and expected outcomes

Working with RTP, RNG, probability models and payout logic

Comparing production data against simulations and expected mathematical behaviour





Investigating discrepancies and improving engine architecture

Helping define the technical direction of future game-engine development

What they're looking for Strong software engineering experience

Proven experience building or owning game-engine, simulation-engine or similarly complex backend systems

Ideally, experience building engine technology from scratch

Strong understanding of mathematical or probability-driven systems

Experience with simulations, RTP, RNG, probability or payout mechanics

High ownership and evidence of delivering complex projects end to end

Ability to work closely with mathematicians and translate mathematical requirements into reliable software

Direct experience within slots, casino or iGaming is highly desirable The technology stack is C++.

This is not a Unity, Unreal, graphics or gameplay-development role . The focus is on the underlying engine responsible for game logic, mathematics, simulations and payout outcomes.

📌 Senior Software Engineer - Game Engine (Madrid)
🏢 Stott and May
📍 Madrid