Tiered storage is a hot topic in the world of data streaming systems, and for good reason. Cloud disks are (really) expensive, object storage is cheap, and in most cases, live consumers are just reading the most recently written data. Paying for expensive cloud disks to store historical data isn’t cost-effective, so historical data should be moved (tiered) to object storage. On paper, it makes all the sense in the world.

Many of today's most highly adopted open source “big data” infrastructure projects – like Cassandra, Kafka, Hadoop, etc. – follow a common story. A large company, startup or otherwise, faces a unique, high scale infrastructure challenge that's poorly supported by existing tools. They create an internal solution for their specific needs, and then later (kindly) open source it for the greater community to use. Now, even smaller startups can benefit from the work and expertise of these seasoned engineering teams. Great, right?

Chances are you probably had a strong reaction to the title of this post. In our experience, Kafka is one of the most polarizing technologies in the data space. Some people hate it, some people swear by it, but almost every technology company uses it.