About the Role An early-stage AI systems company is seeking a Founding Machine Learning Engineer to build its machine learning function and shape the technical direction of post-training and agent systems. You will work closely with the founding team and help set priorities for experiments, infrastructure, and future team growth. What You'll Do • Structure, filter, and score experimental trajectories for training data pipelines. • Design and implement evaluations and benchmarks for model reasoning, planning, and experimental progress. • Build reliable agent environments, tool interfaces, observability systems, and replay infrastructure. • Establish validation and provenance tracking to improve trajectory and data quality. • Set machine learning roadmap priorities across systems, experiments, and hiring. • Guide the technical direction of the machine learning team as it grows. What We're Looking For • At least 3 years of experience in machine learning engineering, building or delivering production machine learning systems. • Production software engineering experience with Python and systems-level programming for machine learning infrastructure. • Hands-on experience with post-training machine learning, evaluation frameworks, and training data pipelines, including structuring, filtering, and scoring data. • Strong understanding of trajectory data, reward structures, tool use, and agent environment design. • Experience building agent environments, reinforcement learning systems, replay tools, or trajectory debugging infrastructure is valuable. • Ability to connect research with production, take ownership, and work effectively in an ambiguous environment. Compensation & Benefits Annual base salary: $100,000 to $250,000 USD. Visa sponsorship is not available. Location On-site in Munich, Germany.