Interesting and possibly relevant to note that SQLite is not your typical opensource project:
"Open-Source, not Open-Contribution: SQLite is open-source, meaning that you can make as many copies of it as you want and do whatever you want with those copies, without limitation. But SQLite is not open-contribution. The project does not accept patches. Only 27 individuals have ever contributed any code to SQLite, and of those only 16 still have traces in the latest release. Only 3 developers have contributed non-comment changes within the previous five years and 96.4% of the latest release code was written by just two people. (The statistics in this paragraph were gathered on 2018-02-05.)"