Backend Engineer

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.