Cloud CIRCUS, a Tokyo-based SaaS company, aims to streamline marketing efforts for businesses in Japan by offering digital tools like BlueMonkey, a CMS platform hosted on AWS. BlueMonkey supports over 2,000 customer websites, each generating extensive access logs, which were initially analyzed using Amazon Athena. However, this approach was slow, costly, and difficult to scale due to the need for thousands of separate queries and unpredictable expenses. To address these challenges, Cloud CIRCUS transitioned to ClickHouse, an open-source, self-managed analytics pipeline that offered faster, more efficient log analysis with fixed costs. This migration has resulted in significant improvements in query speed and cost management, consolidating all logs into a single table and automating data ingestion. With ClickHouse, Cloud CIRCUS now efficiently handles large-scale log analysis, enhancing its ability to support the growing demands of BlueMonkey and its numerous customer websites.