Member of Technical Staff (AI Researcher)

Details

Perplexity is seeking top-tier AI Research Scientists and Engineers to advance its AI products and capabilities. The team is building AI-powered search and agent experiences through Sonar models, Deep Research Agent, Comet Agent, and Search products that handle hundreds of millions of queries and continue to scale rapidly.

Team Structure

Depending on interests and expertise, the role is aligned with one of three specialized teams:

1. Core Research Team (Horizontal): Focuses on generating and improving base models, foundational model capabilities, post-training techniques, reinforcement learning infrastructure, and organization-wide infrastructure.
2. Agent Products Team (Vertical): Focuses on fine-tuning and optimizing models for the Deep Research Agent and Labs/Canvas products, bridging research and product development.
3. Comet Agent Team (Vertical): Develops and enhances the Comet Agent product, focusing on the requirements and optimizations for its specific use cases.

Responsibilities

Research and Development

• Post-train state-of-the-art large language models using supervised and reinforcement learning techniques, including SFT, DPO, and GRPO.
• Leverage query and answer datasets to scale model performance across Sonar, Deep Research, Comet, and Search products.
• Stay current with LLM research, particularly model training, optimization, and personalization techniques.
• Implement preference optimization and personalization capabilities to enhance user experience.
• Develop in-house improvements and optimizations for state-of-the-art models.
• Turn research ideas into algorithms, run experiments, and launch new models.

Infrastructure and Implementation

• Own full-stack data, training, and evaluation pipelines for model development.
• Build robust training frameworks on top of Megatron and PyTorch for post-training LLMs.
• Implement infrastructure and components to support cutting-edge model training at scale.
• Integrate models into the product ecosystem.

Collaboration

• Work closely with engineering teams to integrate models into Perplexity's product suite.
• Collaborate across teams to ensure cohesive AI experiences throughout the platform.
• Partner with product teams to understand user needs and translate them into model improvements.

Requirements

Required

• Proven experience with large-scale LLMs and deep learning systems.
• Strong programming skills in Python and PyTorch; versatility is a plus.
• Experience with post-training techniques and reinforcement learning.
• Self-starter with a willingness to take ownership of tasks.
• Passion for tackling challenging problems.
• Two to six years of experience on relevant projects, depending on seniority level.

Nice to Have

• PhD in Machine Learning, AI, Systems, or a related field.
• Experience post-training LLMs with SFT, DPO, or GRPO.
• C++ and CUDA programming skills.
• Experience building LLM training frameworks.
• Academic publications and research impact.
• Experience with agent systems and multi-step reasoning.
• Background in personalization and preference learning.

Benefits

Full-time U.S. employees receive benefits including equity, health, dental, vision, retirement, fitness, commuter and dependent care accounts, and more. USD salary ranges apply only to U.S.-based positions. Final offer amounts depend on factors including experience and expertise.