Mint Programmers Need to Learn How to Do Math 6
A recent disturbing trend that I've noticed is that more and more programmers I run into seem to be really bad at math. At the very least, I'm starting to think that a few semesters of calculus in college wouldn't have hurt anyone.
Example 1:
Mint is a financial website that recently won first place at the Techcrunch 40 conference here in San Francisco. It aggregates your bank accounts and tells you how you can save money. While checking it out his evening I came across this, which, incidentally, is the same thing that it's been telling me since I signed up:
Come on Mint, this is the core feature of your website. (I'm not counting the account sign in and aggregation piece, as they seem to contract with Yodlee to do that.) How hard is it to properly calculate the above value?
I hate it when a startup spends so long on design that they forget to write solid code. People aren't going to come back if you can't even get this right.
Furthermore, check out the account that they want me to switch over:
Where did they even begin to pull these numbers from? They want me to switch an account with no money on it from a lower rate card to a higher rate card in order to save $278 a year.
At this point I've stopped thinking about math though, and starting thinking about all of the security holes that are probably in this site if they got something this fundamental wrong.
Unfortunately, there's no way in their interface to cancel my account. Wonderful:
These just seem like basic, basic things to me. I don't even know how you say that you're in beta when things like this don't work.
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It does seem that many financial software companies have problems with math. The UK version of QuickBooks quite often doesn't calculate VAT (our version of sales tax) properly. That's why we dumped it.
You would have thought that Intuit might have bothered with a few unit tests wouldn't you?
It seems marginally more forgiveable in a start-up but only just.
@Jack: Well, VAT is similar, yet different from sales tax. And I am not very much surprised that Quicken, being a US creation, does not handle VAT well... (Not that it is difficult to, mind you)
"It seems marginally more forgiveable in a start-up but only just."
Does it? I would say that the one thing I would require a financial management package to do well is math!
Before mint was open, I found a critical XSS vulnerability that allowed me to pretty much do anything JS could off their site. I sent them a semi-weaponized exploit, and their first response was, "Well this server doesn't have passwords on it, so it doesn't matter if they hack it."
This was Mint.com's primary domain. It had a huge XSS hole. And their immediate response was, "This does not impact our security."
They fixed it the next day and grilled me for how I found the bug.
What do sleazy and semi-fradulent marketing tricks have to do with math? I'm sure someone there knows exactly how many people they'll fool with this little trick, and how much money it'll earn them.
Most of the people that use Mint, or this type of financial applications does not know a lot of maths either.