Senior Software Engineer, Weave

Core Weave, the AI Hyperscaler™ acquired Weights & Biases to create the most powerful end-to-end platform to develop, deploy, and iterate AI faster. Since 2017, Core Weave has operated a growing footprint of data centers covering every region of the US and across Europe, and was ranked as one of the TIME
100 most influential companies of 2024. By bringing together Core Weave’s industry-leading cloud infrastructure with the best-in-class tools AI practitioners know and love from Weights & Biases, we’re setting a new standard for how AI is built, trained, and scaled.

The integration of our teams and technologies is accelerating our shared mission: to empower developers with the tools and infrastructure they need to push the boundaries of what AI can do. From experiment tracking and model optimization to high-performance training clusters, agent building, and inference at scale, we’re combining forces to serve the full AI lifecycle — all in one seamless platform.

Weights & Biases has long been trusted by over 1,500 organizations — including AstraZeneca, Canva, Cohere, OpenAI, Meta, Snowflake, Square, Toyota, and Wayve — to build better models, AI agents and applications. Now, as part of Core Weave, that impact is amplified across a broader ecosystem of AI innovators, researchers, and enterprises.

As we unite under one vision, we’re looking for bold thinkers and agile builders who are excited to shape the future of AI alongside us. If you're passionate about solving complex problems at the intersection of software, hardware, and AI, there's never been a more exciting time to join our team.

Weave is Core Weave’s observability, evaluation, and monitoring platform for AI agents and GenAI applications. Our customers rely on Weave to build the auto‑improving loop for their AI agents: including production tracing, offline evaluations, online monitoring and alerting.

We’re looking for Software Engineers to help build and scale Weave. In this foundational role on a small but growing team, you’ll design and ship core functionality, gather feedback directly from users and customers, and continuously improve the product experience. You’ll work closely with cutting‑edge AI builders, developing the next generation of tools that help teams understand, evaluate, and iterate on their AI agents.

• Implement robust and ergonomic APIs.
• Design and build integrations with popular agent harnesses and SDKs such as Claude Code, Codex, pi.dev, OpenAI Agents SDK, etc.
• Scale and improve backend performance to support low‑latency, high‑volume production use cases.
• Build polished and intuitive features such as online LLM judges, playgrounds, evaluations, labeling, and tracing UX.
• Partner directly with users to understand workflows, gather feedback, and rapidly iterate on solutions.

• Bachelor’s degree in Computer Science or related field.
• 8+ years of experience in Software Engineering.
• Deep knowledge of Python and/or Type Script.
• Experience (personal or professional) in building AI agents.
• Ability to operate effectively amid ambiguity and adapt rapidly to a changing environment.
• Previous startup experience is a plus.

• Experience managing large-scale online production services or OLAP databases.

We Believe In Investing In Our People And Value Candidates Who Bring Diverse Experiences — Even If You Aren’t a 100% Match. Here Are a Few Qualities That Tend To Resonate With Our Team.

• You thrive at the intersection of software, hardware, and ML infrastructure — from tuning distributed systems to scaling backend services.
• You’re passionate about building tools that developers love to use — intuitive APIs and UX that bring clarity and speed to AI workflows.
• You’re curious about the full AI lifecycle — from experiment tracking and model deployment to observability and evaluation — and want to shape an end‑to‑end platform that redefines how AI is built and scaled.

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…