`extension-functions.c` include statistical stuff `stdev, variance, mode, median, lower_quartile, upper_quartile`. I have good use of these, and cannot miss them. Separately compiling `extension-functions.c` to a shared object and loading it works without problems for me. I guess that then the math functions of `extension-functions.c` override those that have been added to the Sqlite core in version 3.35 and higher. Presumably there is no significant difference between them, and this is fine.