In the context of running self-hosted services or side projects, synthetic monitoring is a straightforward way to keep an eye on things without getting too complicated.` Checkly offers a feature called multi-step API checks that allows developers to implement arbitrary numbers of requests in steps and custom logic to monitor any HTTP-based service. This feature is ideal for advanced monitoring needs without getting too complicated. To set up monitoring for a self-hosted ClickHouse database, developers can use Checkly's `MultiStepCheck` feature by creating four files: `clickhouse.check.ts`, `clickhouse.spec.ts`, `clickhouse-disk.spec.ts`, and `utils.js`. The `clickhouse.spec.ts` file contains basic checks such as pinging the ClickHouse health endpoint and running a SELECT query to check the database version. The `clickhouse-disk.spec.ts` file is used to check if there are at least 5GB of free disk space left. Once the files are ready, developers can deploy them to Checkly using the `npx checkly deploy` command. With this setup, ClickHouse databases can be continuously monitored for issues and receive alerts through various channels such as SMS, phone calls, Slack, or PagerDuty.