mponomar

We've had databases literally up for 10+ years, through 5-6 major version upgrades. There's been one file format change that required downtime very early on.

It uses components of SQLite, included in-tree.

There's a heavily modified SQLite embedded in Comdb2 for query parsing/planning. There's some auxiliary tools that can optionally use SQLite (or Comdb2). It'll run without installing an SQLite package.