In my case (and I it's very common when you have complex model) the url looks like this: /users/profiles/categories/{cat_id}
But Backbone.iosync only uses the first part as a namespace:
if (params.url) {
params.url = _.result(params, 'url');
} else {
params.url = _.result(model, 'url') || urlError();
}
var cmd = params.url.split('/')
, namespace = (cmd[0] !== '') ? cmd[0] : cmd[1]; // if leading slash, ignore
Which means all models which have a URL that starts with /users/... loose the rest of the URL.