In Short: We're looking for an experienced product engineer to help us scale our platform as we grow.
About LangfuseWe are building the fastest growing open-source LLM engineering platform.
We help engineers and enterprises build and run LLM applications at scale.
We've raised $4m from Y Combinator, Lightspeed and General Catalyst.
Thousands of teams and engineers use Langfuse daily. Thousands are joining every month.
We're a small, focused team working in-person from Berlin, Germany.
Do whatever it takes to build new features for our users. For this you are not afraid to touch FE, BE, SDKs or Docs
You love to communicate with users on a call or in one of our hundreds of slack channels
You will come up with a plan on how to build the next big feature at Langfuse and execute on it
Doing support
Writing docs
Frontend and Backend in Typescript (including Express, NextJs, Tailwind, Prisma, tRPC)
Clickhouse, Postgres, Redis, S3
Client facing SDKs in Python and Typescript
You should be familiar with a majority of these but we trust that you can pick up a new language/framework quickly.
Someone who is able to PM and project manage themselves
Experience building highly reliable, scaling infrastructure
Interest in open source software and talking to users
Hard worker who thrives in a small, accountable team
CS or quantitative degree preferred
Impressive achievements (professional or otherwise)
Bonus points:
Former founder
Experience in SDK design
DX, ML/AI background
Building for very sophisticated technical users
Competitive salary & equity compensation
Strong customer & revenue growth
You are still joining really early
Strong in person engineering culture (Berlin-Mitte)
Extreme autonomy
Performance and learning focused culture
Everyone on the team says: "best place I've ever worked at"
2 short scheduled meetings per week
We can run this process to offer in less than 7 days.
Fill out application
We screen your application
Jump on a intro call with our CTO
Technical Deep Dive interview
Super Day ( half or full day in Berlin Office )
Meet the other founders (short calls)
Decision & Offer
Project you could have built: Infrastructure Evolution Blog Post
Our codebase: GitHub Repository
Ben Kuhn on Impact, Agency and Taste
Who we are & how we work
What is a Product Engineer (PostHog)
Top Skills
What We Do
Langfuse is the 𝗺𝗼𝘀𝘁 𝗽𝗼𝗽𝘂𝗹𝗮𝗿 𝗼𝗽𝗲𝗻 𝘀𝗼𝘂𝗿𝗰𝗲 𝗟𝗟𝗠𝗢𝗽𝘀 𝗽𝗹𝗮𝘁𝗳𝗼𝗿𝗺. It helps teams collaboratively develop, monitor, evaluate, and debug AI applications.
Langfuse can be 𝘀𝗲𝗹𝗳-𝗵𝗼𝘀𝘁𝗲𝗱 in minutes and is battle-tested and used in production by thousands of users from YC startups to large companies like Khan Academy or Twilio. Langfuse builds on a proven track record of reliability and performance.
Developers can trace any Large Language model or framework using our SDKs for Python and JS/TS, our open API or our native integrations (OpenAI, Langchain, Llama-Index, Vercel AI SDK). Beyond tracing, developers use 𝗟𝗮𝗻𝗴𝗳𝘂𝘀𝗲 𝗣𝗿𝗼𝗺𝗽𝘁 𝗠𝗮𝗻𝗮𝗴𝗲𝗺𝗲𝗻𝘁, 𝗶𝘁𝘀 𝗼𝗽𝗲𝗻 𝗔𝗣𝗜𝘀, 𝗮𝗻𝗱 𝘁𝗲𝘀𝘁𝗶𝗻𝗴 𝗮𝗻𝗱 𝗲𝘃𝗮𝗹𝘂𝗮𝘁𝗶𝗼𝗻 𝗽𝗶𝗽𝗲𝗹𝗶𝗻𝗲𝘀 to improve the quality of their applications.
Product managers can 𝗮𝗻𝗮𝗹𝘆𝘇𝗲, 𝗲𝘃𝗮𝗹𝘂𝗮𝘁𝗲, 𝗮𝗻𝗱 𝗱𝗲𝗯𝘂𝗴 𝗔𝗜 𝗽𝗿𝗼𝗱𝘂𝗰𝘁𝘀 by accessing detailed metrics on costs, latencies, and user feedback in the Langfuse Dashboard. They can bring 𝗵𝘂𝗺𝗮𝗻𝘀 𝗶𝗻 𝘁𝗵𝗲 𝗹𝗼𝗼𝗽 by setting up annotation workflows for human labelers to score their application. Langfuse can also be used to 𝗺𝗼𝗻𝗶𝘁𝗼𝗿 𝘀𝗲𝗰𝘂𝗿𝗶𝘁𝘆 𝗿𝗶𝘀𝗸𝘀 through security framework and evaluation pipelines.
Langfuse enables 𝗻𝗼𝗻-𝘁𝗲𝗰𝗵𝗻𝗶𝗰𝗮𝗹 𝘁𝗲𝗮𝗺 𝗺𝗲𝗺𝗯𝗲𝗿𝘀 to iterate on prompts and model configurations directly within the Langfuse UI or use the Langfuse Playground for fast prompt testing.
Langfuse is 𝗼𝗽𝗲𝗻 𝘀𝗼𝘂𝗿𝗰𝗲 and we are proud to have a fantastic community on Github and Discord that provides help and feedback. Do get in touch with us!