Software Engineer - Simulation

Flexion Robotics seeks a Senior Software Engineer - Simulation in Zürich to own and extend the simulation stack for robot learning. The role focuses on advancing simulation fidelity and scalability for humanoid robots, supporting reinforcement learning and real-world deployment.

This role is responsible for owning and evolving the simulation platform that enables robot learning at Flexion Robotics. Simulation is central to scaling intelligence for humanoid robots, and the engineer will shape how robots learn by managing the simulation stack end-to-end.

Responsibilities

• Design, build, and maintain core simulation infrastructure for robot learning.
• Improve simulation accuracy by developing and refining models for contacts, actuators, deformables, and sensors to minimize the sim-to-real gap.
• Increase training speed by optimizing the simulation stack for large-scale parallel reinforcement learning using multi-GPU and multi-node pipelines.
• Extend rendering pipelines for photorealistic visuals and synthetic data generation to support vision-based learning.
• Maintain software-in-the-loop testing systems to validate robot policies and systems in simulation before real-world deployment.
• Work with reinforcement learning, control, perception, and hardware teams to ensure simulation aligns with real-world performance and deployment goals.

Requirements

• Proven experience in building or extending simulation systems for robotics.
• Practical experience with GPU-based simulators such as MuJoco, Isaac Gym, or Isaac Lab.
• Demonstrated success in creating simulation infrastructure for learning-based robotics.
• Strong programming skills in Python and PyTorch.
• In-depth knowledge of physics simulation, including rigid body dynamics, contacts, and actuators.
• Understanding of GPU systems and performance optimization techniques.

Nice to have

• Experience with deformable objects, soft contacts, or complex actuation systems.
• Background in multi-GPU or distributed training systems.
• Familiarity with Nvidia’s Warp.

What the company offers

• Competitive compensation package.
• An opportunity to work at one of Europe’s most ambitious robotics companies.
• A dynamic, collaborative team that values action and progress.

About the company

Flexion Robotics is developing the intelligence layer for next-generation humanoid robots, aiming to move from fragile prototypes to real-world deployment. Founded by leading scientists in robot reinforcement learning from Nvidia and ETH Zürich, the company is backed by top international venture capital firms and has rapidly progressed from initial code to real humanoid capabilities in a short timeframe.

• Focus on accelerating humanoid robot deployment from prototypes to real-world use.
• Founded by experts in reinforcement learning from Nvidia and ETH Zürich.
• Backed by leading international venture capital firms.
• Rapid development cycle, progressing from first code to real-world capabilities in months.