engineering
Posted Feb 17Senior Product Engineer (Growth)
at Langfuse
GermanyRemote
Responsibilities
- ship an OpenClaw integration) and write about it WHAT WE’RE LOOKING FOR MUST-HAVES - Drive to learn fresh things - you experiment on many different topics and come up with ideas - A hang for business - you envision how Langfuse succeeds through product lead growth -
Requirements
- ABOUT LANGFUSE Open Source LLM Engineering Platform that helps teams build useful AI applications via tracing, evaluation, and prompt management (mission https://tracking.us.nylas.com/l/6d586a21a6fc4e1a8aacc7eb75882b72/0/82383757e54352130f65066e1b2fc4708aacab7897561bcb8000fe4c8a9c6a21?cache_buster=1761124921, product https://tracking.us.nylas.com/l/6d586a21a6fc4e1a8aacc7eb75882b72/1/b9fba3a93b6ffcc0f99ecda62767a17cc437fe8fe0b16181d1c43c1391212e3d?cache_buster=1761124921).
- Largest open source solution in this category: trusted by 19 of the Fortune 50, >2k customers, >26M monthly SDK downloads, >6M Docker pulls.
- 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.
- Our existing users also increase their token use and build more LLM based applications and features.
- We sit at the center and enable our users to build LLM applications faster, more reliably and safer.
- You have real data to work with in terms of analytics and users who are the most agile and up-to-date developers building out AI applications - the perfect environment to try big bets and shape them to success.
- Experience in full-stack development - you can ship changes that touch FE and BE in our product with confidence (frontend overhang and collaborate on backend) - SQL skills (for analytics) - You are excited to talk to and think like our users NICE-TO-HAVES -
- Experience with devtools / OSS ecosystems and developer-centric go to market - Taste for UX / Design big plus - Familiarity with AI/LLM Engineering - Former Founders are very welcome for this role!
- TECH STACK We run a TypeScript monorepo: Next.js on the frontend, Express workers for background jobs, PostgreSQL for transactional data, ClickHouse for tracing at scale, S3 for file storage, and Redis for queues and caching.
- New joiners get all PRs reviewed to learn the codebase, patterns, and how the systems work (onboarding guide https://langfuse.com/handbook/product-engineering/how-we-work/onboarding). - We use AI as much as possible in our workflows to make our users happy.
- We encourage everyone to experiment with new tooling and AI workflows.
- WHY LANGFUSE (NOW PART OF CLICKHOUSE) - This role puts you at the forefront of the AI revolution, partnering with engineering teams who are building the technology that will define the next decade(s). - This is an open-source devtools company.
- You’ll own the full delivery end to end. - We're solving hard engineering problems: figuring out which features actually help users improve AI product performance, building SDKs developers love, visualizing data-rich traces, rendering massive LLM prompts and completions efficiently in the UI, and processing terabytes of data per day through our ingestion pipeline. - You'll work closely with the ClickHouse team and learn how they build a world-class infrastructure company.
- The AI space develops at breakneck speed and our customers are at the forefront.
Contact
- We are also hiring for engineering in EU timezones and expect one week per month in our Berlin office (how we work https://langfuse.com/handbook/how-we-work/principles).
- LINKS - We are big fans of PostHog, check out how Engineers on their Growth team are working https://posthog.com/teams/growth - See how we work in our Handbook https://langfuse.com/handbook, especially “Who are our customers?
- https://langfuse.com/handbook/chapters/customers” PROCESS We can run the full process to your offer letter in less than 7 days (hiring process https://langfuse.com/handbook/how-we-hire/hiring-process).
- You should be familiar with a good chunk of this, but we trust you'll pick up the rest quickly (Stack https://langfuse.com/handbook/product-engineering/tech-stack, Architecture https://langfuse.com/handbook/product-engineering/architecture).
- HOW WE SHIP Link to handbook https://langfuse.com/handbook/how-we-work/principles - We trust you to take ownership (ownership overview https://langfuse.com/handbook/how-we-work/ownership) for your area.
- You'll appear on changelog posts https://langfuse.com/changelog for the features you build, and during launch weeks, you'll produce videos https://langfuse.com/blog/2025-10-29-launch-week-4 to announce what you've shipped to the community.
- We're in a period of strong growth: Langfuse is growing organically and accelerating through ClickHouse's GTM. (Why we joined ClickHouse https://langfuse.com/blog/joining-clickhouse) - If you wonder what to build next, our users are a Slack message or a Github discussions post away. - You’re on a continuous learning journey.
Additional details
- 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.
- Previously backed by Y Combinator, Lightspeed, and General Catalyst.
- We're a small, engineering-heavy, and experienced team in Berlin and San Francisco.
- WHY GROWTH ENGINEERING AT LANGFUSE Your work will have an outsized impact.
- Langfuse is growing on an exponential curve while we are adding more users.
- It’s your chance to jump on the curve and increase its slope directly through any wild ideas you have.
- Be at the forefront of agentic development and show the world how to use Langfuse to develop even faster.
- Maybe you believe the future users of Langfuse will be agents and most growth stems from them? Amazing - run an experiment to validate this hypothesis.
- All while learning how the best agentic applications are built.
- YOUR IMPACT Your work directly impacts our most important growth metrics: - Top of Funnel: More customers want to try Langfuse - Activation: Customers see faster time to value - Adoption: More customers adopt all features across our product suite - Customers require less handholding because the product explains it all - Expansion: help customers expand from one product area to all of our offering WHAT YOU’LL DO 1) UNDERSTAND HOW CUSTOMERS USE LANGFUSE - You build and maintain our data stack (Posthog,