Product Designer

About LangfuseOpen Source LLM Engineering Platform that helps teams build useful AI applications via tracing, evaluation, and prompt management (mission, product). We are now part of ClickHouse.We're building the "Datadog" of this category; model capabilities continue to improve, but building useful applications is really hard, both in startups and enterprises.Largest open source solution in this category: trusted by 19 of the Fortune 50, >2k customers, >26M monthly SDK downloads, >6M Docker pulls.We joined ClickHouse in January 2026 because LLM observability is fundamentally a data problem and Langfuse already ran on ClickHouse. Together we can move faster on product while staying true to open source and self-hosting, and join forces on GTM and sales to accelerate revenue.Previously backed by Y Combinator, Lightspeed, and General Catalyst.We're a small, engineering-heavy, and experienced team in Berlin and San Francisco. We are also hiring for engineering in EU timezones and expect one week per month in our Berlin office (how we work).In Short: We're hiring a product designer to own the user experience of the most widely adopted open source LLM engineering platform. Langfuse is used by thousands of AI teams — including 19 of the Fortune 50 — to trace, evaluate, and manage their LLM applications. Our UI is where engineers make sense of complex, data-dense workflows, and we need someone who can make that experience feel effortless.Why Design at LangfuseYour work will shape how engineers build with AI.Langfuse is often the primary interface engineers use to debug, evaluate, and improve their LLM applications. The designs you ship will be used for hours each day by thousands of developers and non-developers. They'll tell you about it in GitHub issues, on X, and in our community Slack channels. Everything we build is open source (MIT-licensed) and immediately visible.The design challenges here are genuinely hard. You're designing for technical users and business users alike who care about information density, speed, and precision. Traces contain dozens of nested LLM calls with massive prompts and completions. Users need to set up evaluators, manage prompt versions, configure integrations, and build monitoring dashboards before they even start analyzing results. You need to make both the setup and the daily use feel intuitive and easy.You will also have direct exposure to how cutting-edge LLM applications are built. Deeply understanding the problems our users solve will make you a better designer and along the way makes you an expert on LLM engineering yourself.You will grow at Langfuse byOwning our product design end-to-end. You'll be the first dedicated designer at Langfuse. Today, our engineers design as they build, which has gotten us far, but we need someone who can elevate the entire experience. You'll own the design system, and visual language across the product. You'll set the standard for how Langfuse looks and feels.Making data-dense interfaces intuitive. Langfuse surfaces traces, scores, costs, latencies, token counts, prompt versions, and evaluation results. You'll figure out how to present complex, nested data in ways that help engineers find what they need fast.Simplifying complex workflows. Our users run evaluations across datasets, compare experiment results, manage prompt versions, and set up monitoring. You'll map these workflows, identify friction, and design flows that feel obvious in hindsight.Collaborating directly with product engineers. You'll pair with engineers, whiteboard solutions together, and ship designs that work within our existing component system (shadcn/ui, Tailwind). You'll create reusable, consistent UI patterns that the whole team can build with.Shipping design straight to code. You'll use AI coding tools to implement smaller design fixes, build components for the design system, and polish UI details yourself. We are not looking for a perfect engineer here but for someone who can help themselv ... (truncated, view full listing at source)