Like Riak you mean? Is that pun or valid criticism.

I think Riak is a very successful product with features (distribution, simplicity, fault tolerance and scalability) that few (if any) others can match.

CouchDB seems to disagree.

More and more of CouchDB gets converted from Erlang to C++ every year since its creation.

The core runtime and data structures are in C++. At this point, Erlang is mostly the negotiator between the nodes.

This schism in implementation is partly why I hated CouchDB back in the day. That and the fact that it's a data Roach Motel.

"Data goes in but never comes out"