ClickHouse Operations Engineer

The role

This role sits in PostHog's core data infrastructure, where ClickHouse underpins every product's ingestion, storage, and querying. The engineer will run the cluster fleet at very large scale, covering provisioning automation, capacity planning against hardware, and per-node performance work. The position also supports a newer effort to build a query optimizer and related performance tooling.

What you would do

• Operate and maintain ClickHouse as the company scales toward trillions of events annually
• Build automated systems for provisioning and scaling large ClickHouse clusters
• Match hardware choices to workload needs, evaluating newer cloud instance types
• Tune performance at the node and instance level
• Work on cutting-edge ClickHouse capabilities such as open-format table support
• Contribute to query performance tooling and a planned ClickHouse query optimizer

What they asked for

• Deep knowledge of ClickHouse or other OLAP database internals, beyond end-user usage
• Hands-on experience automating dynamic instance provisioning
• Working knowledge of Terraform, Ansible, and Kubernetes
• Track record operating high-scale, complex data storage systems
• Comfort with Python and AWS, plus a coordination service such as Zookeeper or an equivalent