Senior Software Engineer (Agentic Search) – Web Rendering (Chromium)

About Nebius: Nebius is leading a new era in cloud infrastructure for the global AI economy. We are building a full-stack AI cloud platform that supports developers and enterprises from data and model training through to production deployment, without the cost and complexity of building large in-house AI/ML infrastructure. Built by engineers, for engineers. From large-scale GPU orchestration to inference optimization, we own the hard problems across compute, storage, networking and applied AI. Listed on Nasdaq (NBIS) and headquartered in Amsterdam, we have a global footprint with R&D hubs across Europe, the UK, North America and Israel. Our team of 1,500+ includes hundreds of engineers with deep expertise across hardware, software and AI R&D. The Product In a rapidly evolving world, trust in AI depends on AI agents being grounded in fresh, verified real-world data. Search is the foundation that makes this possible. We are building an agent-native search platform designed specifically for AI systems rather than human users. Our product provides programmatic, low-latency, and observable search APIs that AI agents use to retrieve, filter, and reason over real-world information at scale. The Role We are looking for a Senior Software Engineer to work on the rendering infrastructure of a novel search engine tailored for agentic AI consumption. In this role, you will focus on loading modern web pages in a browser that we patch and build ourselves, so that content is rendered completely and reliably at a cost that works across billions of pages. You will work inside Chromium to remove what we do not need, make the rest faster and cheaper, and keep our build current as Chromium moves. Your work ensures that high-quality content is consistently available to the indexing and retrieval systems downstream. In this position, your responsibility will be to • Change Chromium in its heavy core (Blink, the V8 integration, the compositor, the network service) to cut CPU, memory and startup cost per page • Strip Chromium down for agent workloads: skip what nobody needs, such as image and media decoding, web font downloads, and rasterization and GPU work where no one needs pixels, while keeping what page scripts depend on to run correctly (style, layout, animation frames, observers), and work out what breaks, or renders differently, when you do • Keep the browser compatible with the web: make sure that what we remove does not change how the sites we load behave or render • Profile and tune fleets of browsers: the process model, memory per renderer, startup, isolation and crash handling • Build the production system around it: how browsers are launched, pooled, recycled and monitored You may be a good fit if you Have 5+ years of experience building production systems, and are an expert in several of the following areas. Inside the browser • Strong C++ in a large, performance-critical codebase, ideally Chromium, Blink or V8, or a comparable browser engine (Rust is a plus) • Chromium architecture: the process model, Mojo IPC, the rendering pipeline (DOM, style, layout, paint, compositing), and the network service • Building, debugging and shipping custom Chromium builds: the build system, tracing, crash analysis, and maintaining patches across releases Performance and systems • Profiling CPU, memory and I/O for browser fleets, with tools such as perf, tracing and flame graphs • Linux process isolation and resource management, concurrency, and memory management • Have run browsers in production, or built the infrastructure that does, and can describe where the time and memory went Strong candidates may also have experience with • Contributions to Chromium, Blink, V8, Firefox, WebKit or another browser engine • Building or maintaining a patched browser that you wrote the patches for • Browser instrumentation, including the Chrome DevTools Protocol • Working familiarity with how modern frontend frameworks render (SSR, CSR, streaming, hydration) • Distributed systems, Kubernetes, and Go or Python The kind of problems you will work on • Cut the cost of loading a page in half. Where do CPU and memory go, and what would you change in the browser? • Turn off the GPU and image decoding for agent workloads. What breaks, and what changes in how pages load and render? • A page runs a script that never yields. How do we detect and stop it without help from the page? • Chromium ships a new version. How do we bring a large set of patches forward in days, not weeks? • Decide when a page is finished, for pages with analytics beacons, long polling and endless scrolling. We conduct coding interviews as part of the process. Benefits & Perks: • Competitive compensation • Career growth and learning opportunities • Flexibility and ownership • Collaborative and innovative culture • Opportunity to work on impactful AI projects • International environment and talented teams What’s it like to work at Nebius: Fast moving – Bold thinking – Constant growth – Meaningful impact – Trust and real ownership – Opportunity to shape the future of AI Equal Opportunity Statement: Nebius is an equal opportunity employer. We are committed to fostering an inclusive and diverse workplace and to providing equal employment opportunities in all aspects of employment. We do not discriminate on the basis of race, color, religion, sex (including pregnancy), national origin, ancestry, age, disability, genetic information, marital status, veteran status, sexual orientation, gender identity or expression, or any other characteristic protected by applicable law. Applicants must be authorized to work in the country in which they apply and will be required to provide proof of employment eligibility as a condition of hire. If you need accommodations during the application process, please let us know.