Creating CouchdDB documents yields strange "lib" exception

I was puzzled about this exception I got when calling n $db.createDoc(myArray);

I got this error message in my browser and couchdb debug log (/var/log/couchdb/couch.log):

The document could not be saved: Object has no property "lib".

{"_id":"_design/memento","_rev":"45-2ea48ca87e0763f81adec1bd7c4b0224","vendor":
{"couchapp": {"evently": {"profile": {"profileReady":
{"after":"function(e, p) {\u000a $$(this).profile =

[... continuing for 100s of lines ...]

I was further puzzled that executing the "Compact & Cleanup..." tools in Futon seemed to (temporrarily) remedy the problem. However, I got this error promptly back in my face so I had to find the cause of it.

It turned out that the include line in my validate_doc_update.js was pointing to a non existing library. Since this Javascript is run on each create, update & delete operation, it failed with an (awfully long and garbled) error message.

Thus, look out that the include lines in validate_doc_update exists relative to where the script itself resides. In my case, I had to change

var v = require("lib/validate").init(newDoc, oldDoc, userCtx, secObj);

to:

var v = require("vendor/couchapp/lib/validate").init(newDoc, oldDoc, userCtx, secObj);