Member of Technical Staff - Post-Training
OUR MISSION
Reflection is a research lab making intelligence open and accessible for everyone to use, customize, and build on. We build open models that let anyone control their intelligence and help shape the future of AI. Our mission: make intelligence open and accessible to all.
ABOUT THE ROLE
- Build systems that transform powerful pre-trained models into aligned and general agents.
- Drive research and engineering initiatives that push the frontier of post-training, from data curation to large-scale optimization.
- Develop data generation pipelines, reward models, reinforcement learning algorithms, and inference-time scaling techniques.
- Collaborate across pre-training and post-training teams to deliver step-function gains in model capability.
- Contribute to shaping our understanding of how large models learn to reason, follow instructions, and improve through reinforcement learning.
ABOUT YOU
- Deep understanding of machine learning fundamentals and practical experience with large-scale LLM training.
- Strong engineering skills, comfortable diving into complex ML codebases and distributed systems.
- Experience improving model behavior through data, reward modeling, or RL techniques.
- Evidence of owning ambitious research or engineering agendas that led to measurable model improvements.
- Thrive in a fast-paced, high-agency startup environment; bias toward action and clarity of execution.
- Able to work fluidly across research and infra boundaries
- Strong communication capabilities and comfort working collaboratively
- Passionate about advancing the frontier of intelligence.
WHAT WE OFFER:
We believe that to make intelligence open and accessible to all, you need to start at the foundation. Joining Reflection means building from the ground up as part of a talent-dense team. You will help define our future as a company, and help define the future of open foundational models.
We want you to do the most impactful work...