Buildkite and ClickHouse: A story of a trillion tests
How Buildkite ingested a trillion test results into ClickHouse Cloud, and the architecture decisions that made it possible.
Buildkite's Test Engine helps engineering teams make builds faster and more reliable with real-time test analytics and intelligent test splitting. Used by customers including OpenAI, Cursor, Slack, and Airbnb, the platform has ingested over a trillion test results into ClickHouse Cloud.
This talk explores the architecture behind that scale: ClickHouse Cloud on AWS operating alongside Rails, Flink, and PostgreSQL. The Buildkite team traces how ClickHouse replaced workloads previously spread across PostgreSQL, Redis, DynamoDB, and Athena, and examines the design choices that made the transition practical. These include using ClickHouse's JSON data type to split flexible key-value test tags into separate columns on disk, Materialized Views to accelerate important queries, and a soon-to-be-open-source Ruby ClickHouse query builder. Viewers will leave with practical ideas for introducing ClickHouse into an existing application stack and using test data to shorten build times.
This is an Open House Roadshow Australia 2026 session.
Recent videos
View all Videos
Open House
Joining the data lake and the warehouse (feat. Jump Trading case study)
Faster JOINs and one query layer across your lake and warehouse. Join us to see how we've supercharged ClickHouse to help you analyze your data, and how Jump Trading is using these features to query petabytes of data at ClickHouse speed!
Open House, User stories
Scaling observability at Nine with ClickHouse
The team at Nine share how they use ClickHouse observability for the Australian Open, Winter Olympics, State of Origin and more.
Follow us
