I feel obligated to mention ledger[0] and hledger[1], those are plain text accounting software, well, as you can guess from their names, they allow you to do personal accounting in plain text.

0: https://ledger-cli.org

1: https://hledger.org

I prefer the simpler beancount: https://github.com/beancount/beancount

All of these use slightly incompatible formats, the irony of which will not escape the educated reader.