I am the CTO/Founder of YugaByte and author of the above post. Thanks for your comments, glad you liked the post! You make a great point about YugaByte DB using Apache Kudu to start out, but wanted to clarify a few things.
* This is a post about our architectural decisions in building a distributed SQL database, and less so about how we actually implement it. Hence there is no mention of any starting points as far as the codebase.
* Also, we have used the RocksDB and PostgreSQL codebases in their entirety in addition to Apache Kudu, and make no secret of this fact (https://docs.yugabyte.com/latest/architecture/concepts/ackno...).