Skip to content

Research Intern RL & Post-Training Systems

121k – 131kSan Francisco, CAML EngineeringOnsiteEntry level
Summary

Research intern role focused on RL and post-training systems for large language models, co-designing algorithms and inference systems. Requires strong research experience in RL/post-training or ML systems, Python proficiency, and willingness to work across abstraction layers.

About the role

Requirements

  • Pursuing a PhD or MS in Computer Science, EE, or a related field (exceptional undergraduates considered)
  • Research experience in one or more of:
    • RL or post-training for large models (e.g., RLHF, RLAIF, GRPO, preference optimization)
    • ML systems (inference engines, runtimes, distributed systems)
    • Large-scale empirical ML research or evaluation
  • Comfortable with empirical research: designing controlled experiments, interpreting noisy results, drawing principled conclusions
  • Strong Python skills for experimentation
  • Willingness to modify inference or training systems (C++, CUDA experience is a plus)

Example Research Directions

  • Inference-Aware RL & Post-Training: Designing RL or preference-optimization objectives that account for inference cost and structure; studying how inference-time approximations affect learning dynamics; analyzing bias, variance, and stability trade-offs.
  • RL-Centric Inference Systems: Developing inference mechanisms for deterministic, reproducible RL rollouts at scale; exploring batching, scheduling, and memory-management strategies optimized for RL workloads; investigating KV-cache policies and runtime abstractions.
  • Scaling Laws & Cost–Quality Trade-offs: Empirically characterizing how reward improvement and generalization scale with rollout cost, latency, and throughput; quantifying when systems-level optimizations change algorithmic behavior.
  • Evaluation & Measurement: Designing rigorous benchmarks and diagnostics for post-training and RL efficiency; studying failure modes in long-horizon training.

Preferred Qualifications

  • Publications at leading ML and NLP conferences (NeurIPS, ICML, ICLR, ACL, EMNLP)
  • Understanding of model optimization techniques and hardware acceleration approaches
  • Contributions to open-source machine learning projects

Internship Program Details

  • Fall internship program spans 12 to 16 weeks (September 14th to December 18th)
  • Opportunity to work with industry-leading engineers and contribute to influential open source projects

Compensation & Benefits

  • Competitive compensation, housing stipends, and other competitive benefits
  • Estimated US hourly rate: $58 to $63 per hour
Skills
PythonCUDAC++Reinforcement LearningRLHFRLAIFGRPODPOInference SystemsDistributed SystemsML Systems
Similar roles at this salary range
All ML Engineering jobs →
Navan

Senior Software Engineer, AI

Build agentic AI workflows and LLM-powered loyalty experiences on the Loyalty Wallet team. Requires 6+ years building production AI/LLM systems with strong backend fundamentals.

113k – 252kNew York, NYML EngineeringOn-site6+ YOELLMRAG
Grafana Labs

Senior AI Engineer

Build and ship AI-powered observability features using LLMs and agent workflows to help users detect, triage, and resolve incidents. Requires strong production software engineering experience plus practical GenAI application skills.

128k – 204kUnited StatesML EngineeringRemote5+ YOEAWSGCP
Zapier

Sr. Applied AI Engineer

Build and evolve shared AI/ML infrastructure including LLM proxy server, observability tooling, and ML Ops platform capabilities. Focus on LLM Ops and ML Ops to improve how models are accessed, monitored, evaluated, deployed, and governed in production.

102k – 287kUnited StatesML EngineeringRemote4+ YOEPythonML Ops
Mozilla

Senior Machine Learning Engineer

Senior ML Engineer focused on fine-tuning and deploying LLMs and generative AI features into Firefox, emphasizing privacy, latency, and user experience.

139k – 218kUnited StatesML EngineeringRemote4+ YOERayLangChain
Twilio

Senior / Staff Applied Research Software Engineer

Senior or Staff Applied Research Software Engineer building AI/ML prototypes and production solutions. Requires 3-5+ years full-stack experience with modern web frameworks, databases, and strong AI-assisted coding skills.

142k – 252kUnited StatesML EngineeringRemote5+ YOEAISQL