I guess you would need to switch to a dotnet native database, like litedb. Even if you would use postgres, there would be native code left, decoupled from the dotnet application though.

It would be interesting though, if it's possible to run webassembly inside the CLR (dotnet runtime).

But I don't really get the issue with native code inside a dotnet application. In the end everything you do in dotnet ends up being executed as native code. Even a simple console.writeline() is implemented in native code.

I've really tried to like LiteDB (mostly because it can use an IO.Stream as the database backing store, which enables lots of fun scenarios), but even light usage mostly resulted in data corruption and inconsistent result sets, something I've literally never seen with SQLite. Plus, I think the project is pretty much dead?

And yes, of course everything ultimately runs as native code, but deployment is a major issue. As long as you only deploy IL (or, possibly at some point, WASM), you only need to worry about the relatively lightweight CLR (the dotnet executable and its direct dependencies) -- it does get a lot more complex once you go beyond that, unfortunately.