Are there any whitepapers or case studies of large-scale production applications using and maintaining a sync function? After using sync gateway with access control for a while, it became more clear to me that writing my own access control API (via node.js or something like that) on top of MongoDB would give better readability and maintainability over a sync function.

(edit) specify mongodb

[Architect from Couchbase]

The formatting and modularization of your sync function code will strongly influence both it's readability and maintainability.

I've published and example of one that is well formatted and modularized. The example includes Navigation Flow, Wireframes, Data Modeling, and a Sync Function (which is the security layer).

https://github.com/waynecarter/couchbase-mobile-examples/wik...

Let me know if you have any other questions around this and I will add it to the example.

Oh, that's awesome! I'd never actually looked carefully at the sync layer, but that seems like a really direct equivalent.