Design theory is that users should be able to opt-in to a phone message broadcasting service given an access phone number and a PIN. Upon joining that system will issue them a one-time-use challenge PIN/password, call them back, and have them enter that password in order to be confirmed and added to the list. Users can broadcast messages to the rest of the list.
Project utilizes Asterisk and AGI to perform scripting functions. Flat files for easy backend database manipulation.
Project link: https://github.com/PhilRW/phoneblast-asterisk