Senior Product Engineer

Stack

Responsibilities

• ▹Own features end-to-end: talk to users, write the spec, ship the code and docs, write the changelog post under your name
• ▹Work across the full stack: React frontend, Next.js backend, ClickHouse analytics, Python and TypeScript SDKs, public docs, Terraform modules
• ▹Talk to users constantly: jump on calls, respond in community channels, route support requests
• ▹Write public documentation about the features you own
• ▹Ship publicly during Launch Weeks: present the features you built to the community, one new feature per day for a week

Requirements

• ▹Experience building features or even entire products from scratch, end-to-end
• ▹Experience shipping user-facing products end-to-end, ideally in TypeScript/React with exposure to data-intensive backends
• ▹Able to manage projects yourself, with strong conviction about what to build and how to ship it
• ▹Taste for great developer experience: API design, UI details, clear documentation
• ▹Interest in open source and genuine excitement about talking to developers about their problems
• ▹CS or quantitative degree preferred

Nice to have

• ▹Experience with ClickHouse, analytics databases, or building complex data visualizations
• ▹Former founder or early startup experience
• ▹Contributions to popular open source projects
• ▹ML/AI background or familiarity with the LLM framework ecosystem

Soft skills

About the company

Langfuse is an open source LLM engineering platform (tracing, evaluation, prompt management) with 21,900+ GitHub stars and 23M+ monthly SDK downloads, now part of ClickHouse. A small, engineering-heavy team based in Berlin and San Francisco, also hiring in EU timezones with one week per month in the Berlin office.