Langfuse

Senior Backend Engineer (Data Infrastructure)

Langfuse
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7 months ago
Paris, France +4 moreSenior

Responsibilities

  • Own and optimize the API-to-ClickHouse ingestion pipeline for throughput, latency, reliability, and cost efficiency.
  • Design ClickHouse schemas, optimize merge strategies, tune batch inserts, and write and review analytical queries.
  • Build infrastructure-heavy features such as asynchronous LLM-as-a-Judge processing, alerting at scale, client-code execution, and batch dataset operations.
  • Run load tests and compare schema, migration, and query changes against real production traffic.
  • Operate Langfuse Cloud across multiple production environments and support deployments from Docker Compose to enterprise-grade Helm charts.
  • Develop backend abstractions that enable product engineers to build data-heavy features efficiently.
  • Plan for infrastructure challenges associated with 10x growth, long-running agent observability, and real-time evaluation.

Requirements

  • Strong backend engineering experience with an interest in database internals, query optimization, and distributed systems.
  • Experience with analytical databases, data pipelines, or high-throughput event processing; ClickHouse experience is a plus but not required.
  • Ability to read and write TypeScript and SQL.
  • Interest in open-source software and comfort discussing scaling challenges with users.
  • Ability to work autonomously and take ownership in a small, accountable team.
  • Preferred qualifications include a CS or quantitative degree, experience with ClickHouse or other OLAP databases, observability infrastructure experience, experience building data-intensive systems at scale, or former founder experience.

Benefits

  • Engineering work is open source and immediately visible to users.
  • Direct collaboration with the ClickHouse database engineering team.
  • Engineering roles are available in EU time zones with an expectation of one week per month in the Berlin office.
  • The company offers a small, engineering-heavy team environment with mentorship through code reviews and close user interaction.
  • The hiring process can proceed from application through offer letter in less than seven days.

Tech Stack

ClickHouseExpressHelmNext.jsPostgreSQLRedisSQLTypeScript

Categories

BackendData Engineering
Langfuse

About Langfuse

11-50 employees
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