Back in 2019 I created a Google Spreadsheet titled "family debts" that allows my family (4 siblings and my parents) to record when we owe each other money, and periodically settle up. I later learned that I recreated Splitwise, but having something like this with trusted folks has been hugely useful. We have over thousand entries, and use it constantly for splitting gifts, buying something at the store for someone, etc.

Om Friday after Thanksgiving I spent half a day building a telegram bot that accepts an address and a list of Amazon links, and in turn orders the item (at a discount since it uses my Amazon credit card), and adds it to the above "family debts" spreadsheet.

I really like the idea of programmable, trusted lending like this, and feel like it could be extended to other groups that you implicitly trust.