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Comment by marcosdumay | Hacker News Reader

There are many really important properties to enforce even on the most basic CRUD system. You can easily say things like "an anonymous user must never edit any data, except for the create account form", or "every user authorized to see a page must be listed on the admin page that lists what users can see a page".

People don't verify those because it's hard, not for lack of value.

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Yes, in fact there is research on type systems to ensure information flow control, avoiding unauthorized data access by construction.

Concrete Semantics [1] has a little example in §9.2.

[1] http://concrete-semantics.org/concrete-semantics.pdf

Yeah fair enough. I can definitely see the value of property-based verification like this and agree that useful properties could be easy to express and that LLMs could feasibly verify them. I think full verification that an implementation implements an entire spec and nothing else seems much less practical even with AI, but of course that is just one flavor of verification.

Even

> "an anonymous user must never edit any data, except for the create account form"

Can quickly end up being

> "an anonymous user must never edit any data, except for the create account form, and the feedback form"

And a week later go to

> "an anonymous user must never edit any data, except for the create account form, the feedback form, and the error submission form if they end up with a specific type of error"

And then during christmas

> > "an anonymous user must never edit any data, except for the create account form, the feedback form, and the error submission form if they end up with a specific type of error, and the order submission form if they visit it from this magic link. Those visiting from the magic link, should not be able to use the feedback form (marge had a bad experience last christmas going through feedbacks from the promotional campaign)"

It is still a small rule, with plenty of value. It's nowhere near the size of the access control for the entire site. And it's also not written down by construction.

It changing with time doesn't make any of that change.

Yes, except their cookie preferences to comply with european law. Oh, and they should be able to change their theme from light/dark but only that. Oh and maybe this other thing. Except in situations where it would conflict with current sales promotions. Unless they're referred by a reseller partner. Unless it's during a demo, of course. etc, etc, etc.

This is the sort of reality that a lot of developers in the business world deals with.

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