Kapacitor is a powerful data processing engine in the TICK stack, offering flexibility and customization options for performing complex tasks beyond what Continuous Queries (CQs) can achieve. Kapacitor can process both stream and batch data from InfluxDB, allowing users to plug in custom logic or user-defined functions to transform and analyze their data. The choice between using Kapacitor instead of CQs depends on the specific use case, such as isolating workload, performing more complex data transformations, downsampling for retention policies, or having a small number of CQs. Stream tasks are suitable for scenarios with limited RAM and short time periods, while batch tasks are better suited for larger datasets and longer retention periods. Kapacitor offers the same functionality as CQs but provides more flexibility and power, making it an attractive alternative for complex data processing needs.