Between that, and packages readily available on most Linux and BSD distros out there (and, in most cases, installed by default), it's well on its way to become a de facto standard system API for relational storage.
It's amusing how Microsoft's different departments keep trying to kill off each other. They spent so much time trying to shove SQL Server Express down everyone's throat, and now everyone gets SQLite included instead.
SQLite is not a competitor to SQL Express, because the latter is still an out-of-proc server. It is a competitor to SQL CE (which shipped its last release to date in 2011, so...).
The nice thing about SQLite is how little it assumes about the world outside. That made it easy to run in WinRT application sandbox with minimal changes; and for quite a while, it was the only local DB readily available to WinRT code written in C# or C++ (JS got IndexedDB).
https://engineering.microsoft.com/2015/10/29/sqlite-in-windo...
Between that, and packages readily available on most Linux and BSD distros out there (and, in most cases, installed by default), it's well on its way to become a de facto standard system API for relational storage.