Open source LLM engineering platform focused on tracing, evals & prompt management

Langfuse, an open-source LLM engineering platform backed by Y Combinator, Lightspeed, and General Catalyst, is seeking a Founding GTM Engineer to pioneer their commercial strategy. The company has raised $4M in seed funding and serves thousands of engineers, including teams at Twilio, Samsara, and KhanAcademy.

This unique role combines solutions engineering with sales, offering the opportunity to build Langfuse's entire go-to-market playbook from scratch. The position leverages a strong inbound pipeline generated by open-source adoption, making it ideal for someone who can bridge technical expertise with commercial acumen.

As the first GTM hire, you'll work directly with the founders to architect and drive Langfuse's commercial engine. The role encompasses technical sales, customer success, and strategic planning. You'll manage everything from lead prioritization and technical POCs to establishing CRM workflows and scaling GTM processes.

The ideal candidate brings a hybrid skill set spanning technical sales, solutions engineering, or customer success. You should be comfortable with CRMs, sales automation, and have a solid understanding of LLM/observability tools. The role requires on-site presence in either San Francisco or Berlin.

Working closely with founders Clemens (COO, sales) and Marc (CEO, product/marketing), you'll join a high-performance team focused on building a small but impactful organization. The company values autonomy and continuous learning, offering significant opportunity for professional growth at the intersection of technical and commercial domains.

This position offers unique advantages:
- Shape the commercial strategy of a fast-growing open-source startup
- Balance hands-on technical work with scalable process design
- Grow at the intersection of solutions engineering and sales
- Work in a high-growth environment with passionate users
- Direct impact on product direction and company success

The role comes with competitive compensation including base salary and equity, reflecting the strategic importance of this position in Langfuse's growth journey.

Founding GTM Engineer role at Langfuse, combining technical expertise with sales to drive growth for an open-source LLM engineering platform.

Founding GTM Engineer

Open source LLM engineering platform helping engineers understand and improve LLM applications

Langfuse is an exciting open-source LLM engineering platform that has raised $4M in seed funding from prestigious investors including Y Combinator, Lightspeed, and General Catalyst. The company is seeking a Platform Engineer/SRE to join their growing team in Berlin, Germany.

The role focuses on scaling the Langfuse platform, which processes millions of events daily through their SDKs. You'll work directly with the CTO and team on critical infrastructure challenges, from query optimization to implementing async processing systems. The tech stack includes TypeScript, PostgreSQL, Redis, and modern cloud technologies.

As an early team member, you'll have significant influence on architectural decisions and product direction. The position requires 3+ years of experience in backend or full-stack development, with a strong background in scaling infrastructure. The company values hands-on experience and offers equity compensation ranging from 0.10% to 0.35%.

The team culture emphasizes performance, learning, and autonomy, with minimal meetings and maximum impact. They work from their Berlin office, fostering close collaboration while maintaining a startup atmosphere. The company follows Y Combinator principles and brings Silicon Valley energy to Berlin.

This is an excellent opportunity for an experienced engineer looking to join a fast-growing open-source project with real-world impact in the LLM space. The role offers both technical challenges and the chance to shape the future of LLM tooling, working alongside a talented team in one of Europe's most vibrant tech hubs.

Senior Platform Engineer/SRE role at Langfuse, an open-source LLM engineering platform in Berlin, focusing on scaling infrastructure and improving platform performance.

Platform Engineer / SRE

Langfuse, an innovative open-source LLM engineering platform backed by Y Combinator, Lightspeed, and General Catalyst with $4M in seed funding, is seeking a Backend Engineer to join their growing team in Berlin, Germany. 

The role focuses on scaling the Langfuse platform, which processes millions of events daily through their SDKs. You'll be working with a modern tech stack including TypeScript, NextJs, Prisma, tRPC, Clickhouse, and PostgreSQL, building critical infrastructure that forms the foundation of their product.

As an early team member, you'll have the opportunity to make significant architectural decisions and contribute to a thriving commercial open-source project. The position requires 3+ years of experience in backend or full-stack development, with a strong background in handling large-scale data systems. A CS/quantitative degree is preferred.

Working directly with the founders, you'll tackle challenges like optimizing database query latency, implementing batched event processing, and supporting self-hosted deployments. The role offers competitive compensation (€70K - €130K) plus equity (0.1% - 0.4%), and requires working from their Berlin office 4-5 days per week.

The company culture emphasizes performance, learning, and autonomy, with minimal meetings and maximum impact. They follow Reed Hastings' 'No Rules Rules' philosophy and embrace Y Combinator's startup ethos. The team currently consists of 7 members, primarily engineers, and they're committed to maintaining a technical-focused environment.

This is an ideal opportunity for an experienced engineer who wants to join an early-stage company and help build it into the leading open-source LLMOps platform. You'll be working in a fast-paced environment where your decisions and code will directly influence the product's success and future direction.

Backend Engineer role at Langfuse, building scalable infrastructure for open-source LLM engineering platform in Berlin

Backend Engineer

Langfuse is building open source dev tooling for LLM apps based on observability/tracing. We have significant traction, are growing fast. We are looking for a full stack product engineer to help us build out our platform in Berlin, Germany.

About Langfuse:
Langfuse is building the open-source LLM engineering platform. We help engineers understand how users interact with their LLM applications and how they can improve them. We have raised a $4m seed round from Y Combinator, Lightspeed and General Catalyst. Thousands of engineers use Langfuse to observe, debug and improve their LLM apps.

What you will be working on:
Your main responsibility will be to add new features and build out existing ones in Langfuse. At the core of Langfuse lies the ingestion of millions of events a day via our SDKs. Once the data is in our database, we visualize it in our UI and run async workflows on top of it in the background.

Projects you would be involved in:
- Our first launch week
- The build out of our model-based evals feature
- Rolling out the LLM Playground and connecting it to other parts of the product
- Maintaining our core integrations and introducing new ones

Stack: Frontend and Backend in Typescript (T3 Stack including NextJs, Tailwind, Prisma, tRPC), Clickhouse, Postgres, Client facing SDKs in Python and Typescript.

The opportunity:
You are joining Langfuse early. We will treat you as a core member of the team from day 1 and you will be incentivized as such. Your decisions and code lie at the foundation of our product. You will contribute to a thriving commercial open source project and build in public. You will own parts of the Langfuse product end-to-end.

Who We Are Looking For:
- Hard worker who thrives in a small and accountable team
- Wants to take ownership in shipping features for a fast growing devtool
- Excited about open source software
- 2+ years of experience in full-stack development
- Impressive achievements from previous careers and side projects

Bonus Points:
- Experience with or interest in UX/UI design and DX
- Started a company before or worked at a very early stage startup
- ML/AI experience

Team, Values & Benefits:
We work in-person from our office in Berlin-Mitte. We aim for 3-5 days in the office a week. Our team culture is built around performance and learning. We want to build a small team of highly motivated, independent and intelligent people.

Langfuse is seeking a Product Engineer to build open source dev tooling for LLM apps in Berlin, Germany.

Langfuse Engineering Jobs

Open source LLM engineering platform focused on tracing, evals & prompt management