Like Wowtoken.app, I care about the privacy of my users like I do myself.
I store as minimal data as is needed to run the service. In the case of GoblinBot, I only store the Discord User ID and what alerts they are subscribed to.
The user can delete their data at any time. DynamoDB stores up to 35 days of Point-in-Time Recovery for the tables for DR purposes.
No user data is ever used outside of the program or for any purposes other than to provide functionality of the program.