Senior Software Engineer, molab at Coreweave

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. Founded in 2017, CoreWeave became a publicly traded company (Nasdaq: CRWV) in March 2025. Learn more at www.coreweave.com. What You’ll Do: At marimo, we’re on a mission to make the world’s best open-source programming environment for working with data, together with a world-class, scalable, and performant cloud-hosted counterpart. marimo is a reinvention of the Python notebook — it feels like a next-gen reactive Python notebook, but is stored as pure Python that can be versioned with Git, deployed as a data app, run as a script, and reused as a module. Incubated initially with scientists at Stanford, marimo is now used by leading companies, labs, and universities around the world, with millions of downloads since launch and over 17,000 stars on our GitHub repository. On the marimo team, we believe that the tools we use shape the way we think — better tools, for better minds. If you're passionate about developer tools, thrive in ambiguity, enjoy solving challenging engineering problems at scale, and yearn for greenfield problems, you'll fit right in. The molab team develops a cloud-hosted marimo notebook service called molab. molab lets anyone in the world experiment with data, build interactive apps, and share their work for free, all using the open-source marimo notebook and accelerated by AI-assisted coding. This is a high impact team and product, undergoing rapid growth and working on many challenging greenfield problems — with an emphasis on building highly available, low latency and fault tolerant systems. About the role: As a senior engineer on marimo's molab team, you will help design and implement the backend architecture of molab, solving for high availability, low latency (both the ability to rapidly spin up and spin down notebook kernels on demand, as well as low latency communication between the notebook frontend and backend), stability, and fraud and abuse. You will also be involved in building product features as needed, such as secret management. Who You Are: • 5+ years of experience in software engineering • Strong fundamentals that are language agnostic • Experience with computer systems, including parallel computing (threading, multiprocessing), concurrency (asynchronous programming), networking/inter-process communication • Experience with containerization, container orchestration (kubernetes), scheduling, networked filesystems, resource allocation, distributed systems, and cloud infrastructure • Experience building highly available, fault-tolerant systems • Strong communication skills, written and verbal† Preferred: • Proficiency with Python and Python packaging • Basic experience with or awareness of the Python stack for AI/ML • Empathy for practitioners and researchers in AI, ML, data engineering, NLP, or other quantitative work 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. • You love to build empower developers by building performant and scalable tools • You’re curious about how developers in AI, ML, and data experiment with models and code • You’re an expert in building highly scalable cloud infrastructure The base salary range for this role is $165,000 to $242,000. The starting salary will be determined based on job-related knowledge, skills, experience, and market location. We strive for both market alignment and internal equity when determining compensation. In addition to base salary, our total rewards package includes a discretionary bonus, equity awards, and a comprehensive benefits program (all based on eligibility). What We Offer The range we’ve posted represents the typical compensation range for this role. To determine actual compensation, we review the market rate for each candidate which can include a variety of factors. These include qualifications, experience, interview performance, and location. In addition to a competitive salary, we offer a variety of benefits to support your needs, including: • Medical, dental, and vision insurance - 100% paid for by CoreWeave • Company-paid Life Insurance • Voluntary supplemental life insurance • Short and long-term disability insurance • Flexible Spending Account • Health Savings Account • Tuition Reimbursement • Ability to Participate in Employee Stock Purchase Program (ESPP) • Mental Wellness Benefits through Spring Health • Family-Forming support provided by Carrot • Paid Parental Leave • Flexible, full-service childcare support with Kinside • 401(k) with a generous employer match • Flexible PTO • Catered lunch each day in our office and data center locations • A casual work environment • A work culture focused on innovative disruption 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. California Consumer Privacy Act - California applicants only 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. As part of this commitment and consistent with the Americans with Disabilities Act (ADA), CoreWeave will ensure that qualified applicants and candidates with disabilities are provided reasonable accommodations for the hiring process, unless such accommodation would cause an undue hardship. If reasonable accommodation is needed, please contact: [Upgrade to PRO to see contact]. 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.