AI Researcher (AI)

Location: San Francisco, Berlin, London, New York City, or Palo Alto

Salary: $220K–$485K annually, plus equity; USD ranges apply to U.S.-based positions, while international salaries are based on the local market.

Company

Perplexity develops AI-powered search and agent experiences, including Sonar models, Deep Research Agent, Comet Agent, and Search products.

What you will do

• Post-train state-of-the-art large language models using supervised and reinforcement learning techniques such as SFT, DPO, and GRPO.
• Use query and answer datasets to improve model performance across search and agent products.
• Develop preference optimization and personalization capabilities for better user experiences.
• Build data, training, and evaluation pipelines and training frameworks on top of Megatron and PyTorch.
• Implement infrastructure for large-scale model training and integrate models into the product ecosystem.
• Collaborate with engineering and product teams to translate user needs into model improvements.

Requirements

• Experience with large-scale LLMs and deep learning systems.
• Strong programming skills in Python and PyTorch.
• Experience with post-training techniques and reinforcement learning.
• Ownership mindset and ability to tackle challenging problems independently.
• 2–6 years of experience on relevant projects, depending on seniority level.

Nice to have

• PhD in machine learning, AI, systems, or a related field.
• Experience with C++ or CUDA, LLM training frameworks, agent systems, multi-step reasoning, personalization, or preference learning.
• Academic publications and research impact.

Culture & Benefits

• Full-time U.S. employees receive equity, health, dental, vision, retirement, fitness, commuter, and dependent care benefits.
• Full-time employees outside the U.S. receive benefits tailored to their region of residence.
• Work across specialized research and product teams focused on core models, agent products, or Comet Agent.