During my first week at American Express I did not have the credentials to install any applications. My manager wanted me to build a prototype and I couldn't install a database. Firebase and other third party was impossible because I had to work on an internal server. I thought SQLite would save my day, but I remembered it being really hard to install and set up. So I had to write my own DB that I called 'stupid-db'. It literally just reads/writes data into a file: https://github.com/songz/stupid-db
SQLite is a library, not a database server. There's no install step - it's a single .C file (and a header, if you're into that). Most of the major scripting languages have rock-solid bindings that don't require any additional system libraries or software installs.
The demo went well.