🛠 Building JAB47: same-looking transactions, different stories

We were working through another case: two transactions, the same payee, the same amount, the same currency. Even the date matches. A duplicate?

Not necessarily. You might buy the same coffee twice in one day at the same place. Two separate purchases, two nearly identical entries.

Currencies make things more interesting. Two purchases with the same price can be converted at different exchange rates, leaving different amounts charged to your account. The reverse can happen too: the amounts charged match, even though the original purchase amounts were different.

Similar entries don’t necessarily mean the same purchase. And different numbers alone don’t tell the whole story.

That creates a tricky problem for a finance app. Miss a genuine duplicate, and your spending looks higher than it was. Treat two real purchases as one, and some of your spending disappears. Either way, “Where did my money go?” becomes harder to answer.

We’ve worked out how to handle these situations and have already built the solution into JAB47. You’ll see it in the app 😉 We’re keeping the implementation details within the team for now.

Another task that initially looks like “just compare two rows.” If only.