"First off, you decided to build on the PostgreSQL
platform--why go there?
"Andy Astor: PostgreSQL has had 20 years of continuous community
development, and today is one of the most active open source
communities on the planet. It is widely considered the most mature
and advanced open source database there is. What we did early last
year was conduct a survey of all open source products available. We
evaluated all of them, including PostgreSQL. We recognized
PostgreSQL as the best base to build this product. To date we've
worked in the lowest level of the PostgreSQL core to ensure that
all four major areas in database programming compatible to open
source development have been touched upon: SQL syntax, triggers,
data types and stored procedures..."