But it is not a layer on top of sqlite_vec, so your logic seems to be: If the tool uses sqlite_vec (which it doesn't) Then it should say so in the readme. You didn't find evidence sqlite_vec in the readme, so your conclusion was that it should be added.

This is seemingly based off of your not liking the author mentioned that it would be the "sqlite of RAG" (which, notably, does not at all imply the use of sqlite, in fact, it suggests this is an alternative to sqlite).

To address your other questions about if the file format is actually a sqlite database, the readme does address that: https://github.com/christopherkarani/Wax?tab=readme-ov-file#...

The fact that the format is append-only seems to rule out that it is sqllite, but I could be wrong.