Why Kaskada?
Kaskada is a library for executing temporal queries over event-based data. An “event” can be any fact about the world associated with a time. For example, a user signing up for a service, or a customer purchasing a product. As additional events occur the computed values may change as well.
Traditional data processing systems are designed to answer questions about the current state of a dataset. For instance, “how many purchases has a given user made?” Over time, the user makes additional purchases and the answer should change. With these traditional data processing systems, the answer changes based on when it is asked.
With Kaskada, the query “how many purchases has a given user made?” is expressed as a Timestream. This represents how the result of that query changes over time for each user. Kaskada makes it easy to combine Timestreams to produce a new Timestream – joining points from each input as needed.