The main back end tool is scrapeomat.
It collects articles from configured sites, storing them in a (postgresql) database. It’s designed to be run as a server on a unix-style box.
Code on github: https://github.com/bcampbell/scrapeomat
There some a few docs in various states of completion. See https://github.com/bcampbell/scrapeomat/blob/master/doc
Provides an HTTP API which front end clients can connect to and retrieve collected articles for analysis.
Clients can then access the collected articles via an HTTP API.
(source code is under cmd/slurpserver at https://github.com/bcampbell/scrapeomat)
The API presented by slurpserver is documented at https://github.com/bcampbell/scrapeomat/blob/master/cmd/slurpserver/api.txt