A computer-implemented method for notifying of content changes includes monitoring, by a computer processor, a content source of a content provider. That monitoring includes periodically reading a Notification as a Service (NaaS) extension in a Rich Site Summary (RSS) feed associated with the content source, where the NaaS extension defines a plurality of interest categories of the content source. New content is identified in the content source, based on periodically reading the NaaS extension, and the new content is associated with a first interest category of the plurality of interest categories. A user is identified as being subscribed to receive notifications of content changes in the first interest category. The user is notified of the new content, responsive to the new content being associated with the first interest category and the user being subscribed to receive notification of content changes in the first interest category.