Member of Technical Staff (Model Behavior)

Perplexity serves tens of millions of users daily with reliable, high-quality answers grounded in an LLM-first search engine and specialized data sources. The Answer Quality team ensures that our prompts, tools, search systems, datasets, and models work together to create the best possible experience for our users. As our product and agent capabilities evolve, we need evaluation systems that are fast, reliable, production-faithful, and actionable. In this role, you will build and improve the technical foundations that support Answer Quality across Perplexity. This includes our shared evaluation infrastructure and the platform used to replay and analyze agent traces. You will work closely with data scientists, engineers, and product teams to identify quality problems, measure their impact, and turn evaluation findings into product improvements. Responsibilities Build shared evaluation infrastructure that helps teams run reliable evals, analyze results, and make product and model decisions Develop the platform for replaying and analyzing agent traces to reproduce production behavior and diagnose failures Build and operate scalable systems for processing, storing, and monitoring interaction, trace, and evaluation data Partner with data scientists, engineers, and product teams to turn answer-quality problems into evaluations, analyses, and product improvements Operate in a small, high-impact team where your work directly shapes how Perplexity measures and improves Answer Quality Qualifications 4+ years of software, data, or machine learning engineering experience shipping and operating production systems Strong proficiency in Python and SQL, with solid fundamentals in system design, data modeling, and distributed systems Experience building big-data systems, including distributed compute, large-scale storage, and high-volume pipelines Demonstrated ownership of ambiguous technical projects from initial design through production operation Ability to work effectively with

Perplexity Computer is one of the defining products of the new era of agentic AI. Millions of people use Perplexity to transform knowledge into action, and the Agent Capabilities team sits at the intersection of frontier AI research and product innovation, building the foundations that shape how users and agents solve increasingly complex tasks. As every major breakthrough in AI models creates new possibilities, the Agent Capabilities team is responsible for turning frontier AI breakthroughs into reusable product capabilities. We are often the first to evaluate emerging model capabilities, determine where they create real user value, and transform them into reliable, scalable, high quality experiences for both users and agents. This is a highly leveraged role with broad ownership at the intersection of frontier AI research, agent systems, platform engineering, and product innovation. Tech Stack : Python | Go | Rust | PostgreSQL | DynamoDB | AWS | TypeScript Why Perplexity is different Craftsmanship . We build high quality, tasteful products targeting both the AI native and AI curious. Ownership . You identify the problem, design the solution and ship it. Entrepreneurship . We think like founders, act with urgency, and hustle to deliver for each other and our users. Scholarship . Work among highly talented peers, pursuing knowledge and truth, upleveling ourselves, our teams, and our products. Partnership . We amplify each others' strengths, break down silos, and give selflessly to help our colleagues deliver excellence. What you'll do Evaluate frontier models against real user tasks, identify useful behaviors and failure modes, and turn the most promising advances into production agent systems. Own the lifecycle from rapid prototyping and evaluation through launch, monitoring, and iteration. Improve agents’ ability to plan, use tools, manage context, recover from errors, and complete long-running tasks reliably. Apply state of the art ML and LLM techniques to design

About Perplexity AI In 2026, we launched Computer, the defining product for the new era of agentic AI. We’ve scaled beyond the millions of people using Perplexity every day for research, shopping, investing and curiosity into a new paradigm of using AI to transform knowledge into action. As an engineer at Perplexity, your role will be to build products and systems that define how AI empowers humans to think, decide and act. You’ll ship fast and work between both product and infrastructure advancements in our technology. Why Perplexity is different Craftsmanship . We build high quality, tasteful products targeting both the AI native and AI curious. Ownership . You identify the problem, design the solution and ship it. Entrepreneurship . We think like founders, act with urgency, and hustle to deliver for each other and our users. Scholarship . Work among highly talented peers, pursuing knowledge and truth, upleveling ourselves, our teams, and our products. Partnership . We amplify each others' strengths, break down silos, and give selflessly to help our colleagues deliver excellence. About the Role Perplexity is looking for a deeply technical software engineer to own and evolve our model serving platform, which is responsible for connecting our products and research systems with our inference layers. This mission-critical system gives teams one fast, reliable interface across providers. You will work at the intersection of distributed systems, AI products, and infrastructure. You will make it dramatically easier for teams across Perplexity to adopt new models, run rigorous experiments, and ship dependable products. The ideal candidate combines sound technical judgment forged in production systems with active curiosity around the rapidly changing capabilities and failure modes of frontier models. You will design core abstractions, lead high-conviction technical decisions, and write production Rust and Python for a service that serves hundreds of millions of model reque

We build and run the inference engine behind every Perplexity query and deploy dozens of model architectures at scale with tight latency and cost budgets. Our stack is Rust, Python, CUDA, and CuTe DSL - and we need another engineer to join us. What you will work on Examples of real work the team does: New models support. Support transformer-based retrieval, text-generation, and multimodal models in our inference infrastructure, from weight loading, request scheduling and KV-cache management to support in API Gateway. GPU kernels migration to CuTe DSL. Port our in-house CUDA kernels to NVIDIA's CuTe DSL so they run on GB200 today and are portable to Vera Rubin racks tomorrow. Rust-native serving runtime. Develop our internal Rust-based inference server to solve all Python pains and keep up with rapidly growing traffic. Performance optimisation. Profile and fix bottlenecks from network ingress through continuous batching and GPU kernel interleaving. Reliability and observability. Build dashboards, alerts, and automated remediation so we catch regressions before users do. Respond to and learn from production incidents. Who we're looking for Deep experience with GPU programming and performance work (CUDA, Triton, CUTLASS, or similar). Any other deep systems programming experience is a plus. You understand modern LLM architectures and are able to bring them up reliably in a production environment. You've built and operated production distributed systems under real load - ideally performance-critical ones. Comfortable working across languages and layers: Rust for the serving runtime, Python for model code, CUDA/CuteDSL for kernels. You own problems end-to-end. You can read a research paper on Monday, write a kernel on Wednesday, and debug a production incident on Friday. Self-directed. You do well in fast-moving environments where the path forward isn't laid out for you. Good if you touched any of ML compilers and framework internals: PyTorch internals, torch.compile, cus

Perplexity is looking for a technical program manager to be the connective tissue between our model providers, engineering, and product teams, driving our core inference platform forward. Perplexity runs one of the highest-throughput inference stacks in the industry, serving Ask, Computer, and API traffic across a large and constantly shifting portfolio of first-party and third-party models. This role sits at the intersection of product, engineering, and finance: you'll orchestrate across model providers and internal teams to keep new models and capacity moving smoothly into production, while executing the roadmap for the inference platform itself. The ideal candidate has strong technical judgment, thrives coordinating across teams and external partners with competing timelines, and is energized by building the operating model for a function that doesn't have much precedent yet. Our Mission Perplexity's mission is to power curiosity. Curious people are the people who drive change in the world. Driving change is a continuous cycle of learning, building, and integrating. Learn: curious people constantly learn new things by asking more. They question the status quo in their own expertise and they constantly learn outside of it. Research is essential to them and never ending. Build: curious people make and create things, to show the world their new answers to problems no one else ever questioned. They take action on what they've learned. Makers need tools to create their products, their companies, their reality. Integrate: they must interact with the world as it is to drive change and adoption. True leaders do not simply build something and hope. They must have armies of agents and workers who can constantly work in millions of small ways. What You'll Do Execute the roadmap for the inference platform request handling, rate limits and quotas, usage controls, and the reliability and observability surface engineering and product teams depend on Be the connective tissue bet

About the Role The Infrastructure team builds and operates the foundational systems behind Perplexity’s products. At Perplexity, infrastructure sits on the critical path of every answer, supporting real-time search, retrieval, model serving, and agent workloads where latency, reliability, and rapid iteration directly shape the user experience. This role is for strong infrastructure engineers whose experience spans multiple domains and who are energized by cross-cutting problems that do not fit neatly within a single platform team. You do not need to be a specialist in every area. Scope ranges from owning major production systems to setting technical direction across teams, leading complex infrastructure programs, and shaping infrastructure strategy across the organization. If a specialized Cloud Infrastructure, Storage Platform, Backend Platform, Data Platform, Connector Platform, or AI Acceleration role clearly matches your expertise and interests, apply directly to it. If your experience spans several infrastructure domains or you are most energized by cross-cutting systems problems, apply here. Submit one application, and we will consider you across the Infrastructure organization. Key Responsibilities Own cross-cutting infrastructure problems that span compute, storage, networking, data, deployment, and reliability, including eliminating bottlenecks across retrieval and serving paths, building shared abstractions across deployment environments, and resolving failure modes that cross platform boundaries. Design, build, and operate distributed infrastructure supporting Perplexity’s consumer, AI, and enterprise workloads, owning systems from architecture through production operation. Identify gaps between existing platforms and build shared abstractions, automation, and tooling that make infrastructure easier and safer to use. Improve system performance, availability, scalability, and cost-efficiency across online request traffic and background workloads. Debug com