Senior Backend Engineer (Data Infrastructure)

Stack

Responsibilities

• ▹Own and optimize the ingestion pipeline (from API to ClickHouse) for throughput, latency, reliability, and cost efficiency
• ▹Design ClickHouse schemas, tune merge strategies and batch inserts, write and review analytical queries powering dashboards
• ▹Build new infrastructure-heavy features (e.g. LLM-as-a-Judge, alerting at scale, client-code execution, batch dataset operations)
• ▹Validate changes against real production data with load tests before rolling out new schemas, migrations, or query optimizations
• ▹Scale infrastructure for new product directions such as long-running agent observability and real-time evaluation
• ▹Operate Langfuse Cloud across multiple production environments and make self-hosting effortless, from a single Docker Compose setup to enterprise-grade Helm charts

Requirements

• ▹Strong backend engineer who gets excited about database internals, query optimization, and distributed systems
• ▹Enjoys working with large volumes of data
• ▹Experience with analytical databases, data pipelines, or high-throughput event processing (ClickHouse experience a plus, not required)
• ▹Self-organized, with strong opinions about what to build and how to ship it
• ▹Comfortable reading and writing TypeScript (backend) and SQL
• ▹Interest in open source software and genuine enjoyment talking to users about their scaling challenges
• ▹Thrives in a small, accountable team where your output is visible and matters
• ▹CS or quantitative degree preferred

Nice to have

• ▹Experience with ClickHouse, other OLAP databases, or observability infrastructure
• ▹Former founder
• ▹Background in building data-intensive systems at scale

Soft skills

What we offer

• ▹Remote work in EU timezones, with one week per month in the Berlin office
• ▹Fast hiring process, offer within 7 days
• ▹Direct access to the ClickHouse database engineering team, since Langfuse is now part of ClickHouse

About the company

Langfuse is an open source LLM engineering platform that helps teams build useful AI applications through tracing, evaluation, and prompt management. Since joining ClickHouse in January 2026, it has become the largest open source solution in its category, trusted by 19 of the Fortune 50 and 2,000+ customers, with over 26M monthly SDK downloads. The team is based in Berlin and San Francisco and was previously backed by Y Combinator, Lightspeed, and General Catalyst.