Principal Machine Learning Engineer, Applied AI
$252k - $336k • Cambridge, MA USA; San Francisco, CA USA • Full-time
Posted 24d ago
About the job
Lila Sciences is seeking a Principal Machine Learning Engineer to join their growing Applied AI organization. This role focuses on adapting and improving AI models for customer-specific scientific needs, bridging the gap between cutting-edge model capabilities and real-world applications. You will be instrumental in shaping how Lila's AI models are fine-tuned, evaluated, and integrated into reliable workflows for customers. This is a senior individual contributor position requiring deep, hands-on expertise in model post-training, evaluation, and production ML systems.
Responsibilities
- Apply expertise to bridge the gap between AI model capabilities and customer-specific scientific workflows.
- Lead post-training efforts using SFT and RL methods (DPO, PPO/GRPO) to align model behavior with customer requirements.
- Build and manage evaluation loops to assess model quality, reliability, and customer fit.
- Translate customer feedback and data signals into actionable model improvement cycles.
- Collaborate with AI researchers to integrate model advancements into usable product features.
- Work with software engineering teams to embed model behavior into end-to-end product workflows.
- Debug complex model failures using traces, evaluations, and customer feedback.
- Mentor other engineers and share best practices for model adaptation, evaluation, and deployment.
Requirements
- Minimum 2-3 years of hands-on experience in post-training (SFT, RL methods like DPO/PPO/GRPO) and evaluation system design.
- Strong software engineering skills in Python and modern ML frameworks like PyTorch.
- Demonstrated ability to quickly debug ambiguous, high-stakes model behavior using data and qualitative feedback.
- Experience leading technical initiatives across research and engineering teams.
- Deep familiarity with large language models, multi-modal models, or agentic AI systems.
- Clear communication skills for translating technical concepts and customer needs.
Benefits
- Competitive base compensation with bonus potential
- Generous early-stage equity
- Comprehensive medical, dental, and vision coverage (U.S.)
- Employer-paid life and disability insurance (U.S.)
- Flexible time off with generous company-wide holidays (U.S.)
- Paid parental leave (U.S.)
- Educational assistance program (U.S.)
- Commuter benefits, including bike share memberships (U.S.)
- Company-subsidized lunch program (U.S.)
- International benefits tailored to region