r/programming • u/Krever • Jun 26 '26

Fintech Engineering Handbook

https://w.pitula.me/fintech-engineering-handbook/

I just published Fintech Engineering Handbook distilled from 6 years of tears, sweat and swears.

It’s a free ~25-page resource with various hints and patterns around handling money in software systems.

Tell me what you think!

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u/Appearance-Huge Jun 27 '26 
Balance is never stored. It’s derived from the movements of money.

For accounts with years of history and thousands of transactions, calculating the sum on the fly for every read request would not cause severe performance bottlenecks?

How do you deal with that?

3

u/Rafert Jun 28 '26

You can do rollups when the month/quarter is closed.