AI Research Lead

Perplexity is seeking an exceptional AI Research Tech Lead to drive our research strategy and lead the development of our in-house Online LLMs, the Sonar models. In this leadership role, you will set the macro research direction across different modalities, mentor a team of researchers, and take advantage of our rich query/answer dataset to continue scaling our Sonar model performance and deliver the SOTA Online LLM experience to our users. RESPONSIBILITIES RESEARCH LEADERSHIP & STRATEGY - Define and execute the macro research direction across multiple modalities, including post-training LLMs for agent trajectories and future mid-training initiatives - Lead strategic research planning and roadmap development to advance Sonar model capabilities - Drive innovation in supervised and reinforcement learning techniques for query answering - Collaborate with leadership to align research priorities with product and business objectives TEAM DEVELOPMENT & MENTORSHIP - Coach and mentor a team of AI research scientists and engineers, fostering their technical and professional growth - Establish the long-term macro research direction across the team, including our direction across different modalities - Lead hiring and onboarding of new research talent - Create a collaborative environment that encourages knowledge sharing and innovation TECHNICAL EXCELLENCE - Post-train SOTA LLMs on query answering using cutting-edge supervised and reinforcement learning techniques - Own and optimize the full stack data, training, and evaluation pipelines required for LLM post-training - Deliver Sonar models that provide SOTA query answering performance - Drive research into agent trajectories and multi-modal capabilities - Lead the technical roadmap for eventual mid-training investments CROSS-FUNCTIONAL COLLABORATION - Work closely with engineering teams to integrate Sonar models into our product - Partner with product teams to understand user needs and translate them into research priorities - Collaborate with data teams to leverage our unique query/answer dataset effectively - Communicate research progress and findings to stakeholders across the organization QUALIFICATIONS REQUIRED - Minimum of 5 years of experience working on relevant AI/ML projects with 3**+ years in a technical leadership role** - Proven track record of leading and mentoring technical and research teams - A Computer Science graduate degree at a premier academic intitution - Deep expertise with large-scale LLMs and Deep Learning systems - Strong programming skills with versatility across multiple languages and frameworks - Demonstrated ability to set technical vision and drive execution - Experience with pre-training and post-training techniques (self-supervised learning along with SFT/DPO/GRPO/PPO) - Self-starter with exceptional ownership mentality and ability to work in ambiguous environments - Passion for solving challenging problems and pushing the boundaries of AI research NICE-TO-HAVE - PhD in Machine Learning, Computer Science, or related areas - Experience with agent-based AI systems and multi-modal model development - Background in mid-training or pre-training of large language models - Publications in top-tier AI/ML conferences - Experience in fast-paced startup environments - Track record of translating research into production systems