Engineering Manager - Workers Runtime, Edge Team

Job description

About Us At Cloudflare, we are on a mission to help build a better Internet. Today the company runs one of the world’s largest networks that powers millions of websites and other Internet properties for customers ranging from individual bloggers to SMBs to Fortune 500 companies. Cloudflare protects and accelerates any Internet application online without adding hardware, installing software, or changing a line of code. Internet properties powered by Cloudflare all have web traffic routed through its intelligent global network, which gets smarter with every request. As a result, they see significant improvement in performance and a decrease in spam and other attacks. Cloudflare was named to Entrepreneur Magazine’s Top Company Cultures list and ranked among the World’s Most Innovative Companies by Fast Company. At Cloudflare, we’re not looking for people who wait for a polished roadmap; we’re looking for the builders who see the cracks in the Internet that everyone else has simply learned to live with. We value candidates who have the instinct to spot a "normalized" problem and the AI-native curiosity to create a solution using the latest tools. Our culture is built on iteration, leveraging AI to ship faster today to make it better tomorrow, while ensuring that every improvement, no matter how small, is shared across the team to lift everyone up. If you’re the type of person who values curiosity over bureaucracy, and that AI is a partner in solving tough problems to keep the Internet moving forward, you’ll fit right in. Available Locations: Austin, Lisbon, or London (Hybrid) About the Role Emerging Technologies & Incubation (ETI) is where new and bold products are built and released within Cloudflare. Rather than being constrained by the structures which make Cloudflare a massively successful business, we are able to leverage them to deliver entirely new tools and products to our customers. Cloudflare’s edge and network make it possible to solve problems at massive scale and efficiency which would be impossible for almost any other organization. The Workers Runtime team delivers features and improvements to our Runtime which actually executes customer code at the edge. We care deeply about increasing performance, improving JS API surface area and compiled language support through WebAssembly, and optimizing to meet the next 10x increase in scale. The Runtime is a hostile environment - system resources such as memory, cpu, I/O, etc need to be managed extremely carefully and security must be foundational in everything we do. Our work is deeply systems-oriented. We build and maintain the C++ and Rust codebase that embeds the JavaScript engine, manages isolate lifecycles, enforces resource limits (CPU, memory, I/O), and orchestrates how customer scripts are loaded, cached, and executed. We operate in a hostile multi-tenant environment where security must be foundational — from side-channel attack mitigations to isolate sandboxing — and performance is measured in microseconds. Responsibilities You will lead the Workers Runtime - Edge team, owning the runtime service in production across Cloudflare’s fleet and driving the architectural evolution of the platform. • Lead a team of senior systems engineers working in C++ and Rust on one of Cloudflare’s most performance-critical and security-sensitive services. • Drive major infrastructure initiatives, including migrating legacy systems, redesigning core abstractions, and laying the groundwork for next-generation runtime architecture. • Own reliability and release safety for a service handling tens of millions of requests per second. • Improve release processes, invest in health monitoring and automated rollback, and help the team ship changes confidently at scale. • Make prioritisation calls between customer-unblocking feature work and foundational investment in security, reliability, and developer velocity. • Partner closely with adjacent teams across the Developer Platform to ensure the runtime supports the broader product roadmap, including compute, storage, networking, and observability. • Hire, grow, and develop strong systems engineers; set clear expectations, provide technical mentorship, and create an environment where people do their best work. Desirable Skills, Knowledge & Experience • Experience leading a team. • Comfortable leading and hiring a team that builds low-level distributed systems. • Strong planning skills, with experience creating teams and overseeing execution to meet commitments predictably. • Comfortable building developer-loved APIs that scale. • Track record of leading a team through hiring, onboarding, and professional development. • Ability to explain both the “why” and the “how.” • Experience implementing tools, process improvements, internal instrumentation, methodologies, and resolving blockages. • At least 4 years of recent professional experience with C++ or Rust. • Solid understanding of computer science fundamentals, including data structures, algorithms, and object-oriented or functional design. • Deep understanding of the web and technologies such as web browsers, HTTP, JavaScript, and WebAssembly. • Strong understanding of Linux systems programming, process models, and networking. Bonus Points • Experience building high-performance distributed systems. • Experience working with cloud platforms, especially server-less platforms. • Experience with the internals of JS engines such as V8, SpiderMonkey, or JavaScriptCore. • Experience with standalone WebAssembly runtimes such as Wasmtime, Wasmer, Lucet, etc. • Deep Linux/UNIX systems, kernel, or networking knowledge. • Contributions to large open source projects. • Experience working in low-latency real-time environments such as game streaming, game engine architecture, high-frequency trading, or payment systems. • Experience debugging, optimizing, and identifying failure modes in a large-scale Linux-based distributed system. Compensation Compensation may be adjust