Principal Engineer in London

CoreWeave is The Essential Cloud for AI™. Built for pioneers by pioneers, CoreWeave delivers a platform of technology, tools, and teams that enables innovators to build and scale AI with confidence. Trusted by leading AI labs, startups, and global enterprises, CoreWeave combines superior infrastructure performance with deep technical expertise to accelerate breakthroughs and turn compute into capability.

What You’ll Do: The Monolith AI Engineering Team at CoreWeave is responsible for building and scaling the core platform that powers the world’s most advanced engineering simulation and AI workflows. From evolving distributed architecture to enabling the next generation of agentic applications and physical AI, this team delivers the performant, reliable, and scalable foundation trusted by the world’s largest engineering companies.

About the role: We’re seeking a Principal Software Engineer to lead the architectural evolution of our platform as we scale to meet growing demand from the world’s largest engineering companies. This is a hands-on technical leadership role where you’ll drive critical architectural initiatives while mentoring our engineering team. You’ll own — in conjunction with the VP of Engineering — the technical vision and execution of our platform’s evolution to a more distributed architecture, making it agentic ready for the next generation of AI applications.

In this role, you will:

• Technical Leadership & Architecture
  • Drive the ongoing transition from monolithic to distributed architecture.
  • Design and implement architecture to be agentic ready, enabling rapid deployment of AI products and MCP server integrations.
  • Own technical decisions balancing immediate business needs with long-term architectural goals.
• Hands-On Development
  • Write production-quality Python code for critical platform components.
  • Build and optimize distributed compute services.
  • Implement reliable workflow orchestration patterns.
• Team Mentorship & Collaboration
  • Mentor mid-level developers, elevating the technical capabilities of the entire team.
  • Establish engineering best practices and architectural patterns.
  • Collaborate with product and business stakeholders to translate requirements into technical solutions.
  • Guide technical decision-making and prioritization across the engineering organization.
  • Interview and onboard new engineers.

Who You Are:

• 12+ years of software engineering experience with at least 2 years in principal/staff engineering roles.
• Expert-level Python development skills with production experience at scale.
• Deep expertise in distributed systems architecture.
• Strong Kubernetes experience with production workloads.
• Hands-on experience with workflow orchestration tools (Temporal, Airflow, Kubeflow, or similar).
• Cloud platform expertise (AWS required, Azure & GCP beneficial).
• Experience with data processing frameworks (Spark, Athena, Ray, or similar).
• Experience with systems having ML Engineering and MLOps aspects.
• Proven track record of leading architectural transformations in growing companies.
• Excellence in technical communication and stakeholder management.

Wondering if you’re a good fit? We believe in investing in our people, and value candidates who can bring their own diversified experiences to our teams — even if you aren’t a 100% skill or experience match. Here are a few qualities we’ve found compatible with our team. If some of this describes you, we’d love to talk.

• Technical Excellence: You write clean, maintainable code and design systems that scale.
• Pragmatic Problem-Solver: You balance perfectionism with shipping, making smart trade-offs between short-term delivery and long-term goals.
• Strong Leadership: You proactively identify problems and drive solutions forward.
• Mentorship Mindset: You elevate others through knowledge sharing and patient guidance.
• Ownership Mentality: You take full responsibility for outcomes and drive initiatives to completion.
• Customer Obsession: You understand that our success is measured by our customers’ success.

Why CoreWeave? At CoreWeave, we work hard, have fun, and move fast! We’re in an exciting stage of hyper-growth that you will not want to miss out on. We’re not afraid of a little chaos, and we’re constantly learning. Our team cares deeply about how we build our product and how we work together, which is represented through our core values:

• Be Curious at Your Core
• Act Like an Owner
• Empower Employees
• Deliver Best-in-Class Client Experiences
• Achieve More Together

We support and encourage an entrepreneurial outlook and independent thinking. We foster an environment that encourages collaboration and enables the development of innovative solutions to complex problems. As we get set for takeoff, the organization's growth opportunities are constantly expanding. You will be surrounded by some of the best talent in the industry, who will want to learn from you, too. Come join us!

To fulfil our obligation to protect client data, successful applicants offered employment with CoreWeave will be required to complete a basic criminal record check, conducted in compliance with GDPR. Employment offers are conditional upon receiving satisfactory check results.

What We Offer: In addition to a competitive salary, we offer a variety of benefits to support your needs, including:

• Family-level Medical Insurance
• Family-level Dental Insurance
• Generous Pension Contribution
• Life Assurance at 4x Salary
• Critical Illness Cover
• Employee Assistance Programme
• Tuition Reimbursement
• Work culture focused on innovative disruption

Benefits may vary by location.

Our Workplace: While we prioritize a hybrid work environment, remote work may be considered for candidates located more than 30 miles from an office, based on role requirements for specialized skill sets. New hires will be invited to attend onboarding at one of our hubs within their first month. Teams also gather quarterly to support collaboration.

CoreWeave is an equal opportunity employer, committed to fostering an inclusive and supportive workplace. All qualified applicants and candidates will receive consideration for employment without regard to race, color, religion, sex, disability, age, sexual orientation, gender identity, national origin, veteran status, or genetic information.

CoreWeave does not accept speculative CVs. Any unsolicited CVs received will be treated as the property of CoreWeave and your Terms & Conditions associated with the use of CVs will be considered null and void.

Export Control Compliance: This position requires access to export controlled information. To conform to U.S. Government export regulations applicable to that information, applicant must either be (A) a U.S. person, defined as a (i) U.S. citizen or national, (ii) U.S. lawful permanent resident (green card holder), (iii) refugee under 8 U.S.C. § 1157, or (iv) asylee under 8 U.S.C. § 1158, (B) eligible to access the export controlled information without a required export authorization, or (C) eligible and reasonably likely to obtain the required export authorization from the applicable U.S. government agency. CoreWeave may, for legitimate business reasons, decline to pursue any export licensing process.