UNNotificationServiceExtension: memory limit?

Question

I am trying to implement a UNNotificationServiceExtension, but my code does not seem to work often, just by specifying

Program ended with exit code: 0"

I am trying to use the Sqlite3 FMDB module in an extension, and it seems that I can work with memory limitations inside the extension. Are there any documented memory restrictions in these extensions? Are there any strategies that will help me take them into account, or will I just have to admit that I cannot add complex functionality to the extension?

Running through the tools shows that it reaches 3.24 MB. And NSExtensionMain is 68% of this, so I don’t think I can reduce a lot.