What are the responsibilities and job description for the Senior Engineer, Physics & Gameplay (Unreal Engine 5 / Sports) position at Refactor Games?
Refactor Games is a AAA sports video game studio. We are developing the next generation of professional football (soccer) video games using Unreal Engine 5.
We’re looking for a Senior Gameplay Engineer who specializes in gameplay physics, real-time math systems, and deterministic simulation. You’ll be responsible for developing core systems that drive realistic player movement, ball dynamics, collisions, and interaction fidelity—across animations, input, and networked simulation.
- Player movement systems (running, turning, foot planting, shielding)
- Ball physics and interaction with players and environment
- Simulating the Magnus Effect, ie, how the ball’s air spin affects its movement.
- Ground contact, friction, bounce, spin, drag, deflection, and deformation
- Predictive ball trajectories, skill shot curves, and passing vectors
- Tackle physics, foot-to-ball contact accuracy, and physicality tuning
- Implementing physics-assisted animation blending (ragdoll, partial IK)
- Synchronizing physics simulation in online multiplayer contexts
- Advanced use of Chaos Physics and custom math functions in UE5
- 5 years experience as a gameplay or physics engineer on real-time 3D games
- Strong C skills with deep understanding of vector math, linear algebra, and kinematics
- Experience with Unreal Engine 5 gameplay systems (Actor, Component, Network Replication)
- Hands-on experience tuning physics parameters for gameplay feel
- Ability to build and maintain deterministic, frame-accurate simulations
- Experience profiling and optimizing physics in real-time environments
- Shipped a sports title (EA FC, Pro Evo, NBA2K, Madden, etc.)
- Experience building custom physics systems or modifying existing engine physics
- Understanding of soccer rules, tactics, and how real player physics should feel
- Familiarity with animation systems, IK, and motion synthesis techniques
This is a high-ownership role for someone who lives and breathes gameplay physics and has strong opinions about what makes a sports game feel right. If you’ve ever paused a match to tweak acceleration curves or adjust collision fidelity—you’ll fit right in.