About
Perplexity develops AI systems for search, reasoning, and complex problem-solving. Its work spans search and retrieval, LLM post-training, multi-agent training, and the systems that support these capabilities, including models, agent harnesses, and search infrastructure.
Responsibilities
•Push search and agent quality forward by improving models, training data, tools, and system design
•Develop LLM post-training methods, including reinforcement learning, to improve reasoning, search, tool use, and task completion
•Train and evaluate multi-agent systems, exploring how agents divide work, share information, and coordinate
•Design and build agent harnesses, including tools, context management, execution environments, and orchestration for reliable multi-step work
•Improve retrieval and ranking models and the search interfaces agents use to find and assess information
•Build datasets, reward signals, and evaluations that expose meaningful failures and guide improvements
•Own experiments end to end, from hypothesis through scalable training, deployment, and measurable gains in quality, latency, and cost
•Collaborate with AI, Search, Infrastructure, Data, and Product teams to bring new capabilities into production
Requirements
•Proven track record of building and shipping ML systems, with deep experience in one or more of LLM post-training, reinforcement learning, search and retrieval, or agent systems
•Strong software engineering skills and ability to work across model training, experimentation infrastructure, and production systems
•Experience designing rigorous evaluations, diagnosing failures, and translating experimental results into practical improvements
•Comfortable with open-ended problems requiring research judgment and hands-on engineering
•Strong ownership, curiosity, and drive to carry ideas through to working systems
•Depth in a relevant area and ability to learn across the stack; prior expertise in every listed area is not expected
Nice to have
•Training models to use tools or complete multi-step tasks
•Multi-agent training, coordination or evaluation
•Building agent harnesses
•Distributed training systems or scalable inference infrastructure
•Large-scale retrieval, ranking or recommendation systems
Conditions
No conditions stated in the posting.
