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The $440M software error at Knight Capital (2019)

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Re: The $440M software error at Knight Capital (2019)

#81
post #52
post #2

The OP details how poor software engineering practices brought down a 1.4B market marker with 1400 employees in 2012. Some of the issues mentioned include: - Keeping synthetic test data generation as part of a production build. - Keeping dead code for years. - Re-purposing a feature flag. - Refactoring without regression tests. - Manual deployments without peer reviews. They forgot to update one of their servers with…

Repurposing feature flags is some kind of next dimension horror for me. We've got quite a few of these to deal with, and if someone started changing what they mean we'd be fucked super fast. Simply suggesting that we alter the meaning of an existing FF would result in the resignation of a non-zero number of project managers on my team. Rolling back code is another thing I have no tolerance for anymore. The only optio…

The only thing worse that comes to mind than repurposing flags is re-using UUIDs, which I have seen some production DB do (no, not mine, thank you very much!).

Reusing the RAM occupied by flags might be do-able in a clean way using guards like the structured enum in Rust, which permits unions (objects that occupy the same space) that always have the right type (i.e., the compiler has knowledge what is in there at each point in time). This mechanism could in theory be extended beyond type-safety to accommodate other contexts in systems programming use cases where memory usage is extremely important.

Re: The $440M software error at Knight Capital (2019)

#83

Earlier quoted context omitted.

> but we can’t really drop N from the acronym without a replacement Huh, yeah. That would be quite a GAAF. Gotta come up with something before Netflix is forced out of the FAANG club.

I’ve seen MAAM being used.

When FB took it's huge hit I saw people using MANGA. But again if we drop the N...not great.

Re: The $440M software error at Knight Capital (2019)

#84
What's amazing to me is that there are many software engineers here who can recognize how errors like this can so easily creep into software (some would say they're inevitable in any sufficiently complex software) but they still somehow think immutable smart contracts on blockchains are somehow still the future.

Crazy.

Re: The $440M software error at Knight Capital (2019)

#86

Earlier quoted context omitted.

I'm picturing them arguing vigorously over what character the word "bracket" specifies in American versus British English.

Are brackets different in American English? I'd say the Queen should order a second burning down of Washington but, the way things are going, the locals will probably get to it soon.

parens: ()

brackets: []

braces:{}

Versus:

brackets: ()

square brackets: []

curly brackets: {}

Still drives me less mad than "inverted commas" though.

Re: The $440M software error at Knight Capital (2019)

#87

Earlier quoted context omitted.

I'm picturing them arguing vigorously over what character the word "bracket" specifies in American versus British English.

Are brackets different in American English? I'd say the Queen should order a second burning down of Washington but, the way things are going, the locals will probably get to it soon.

One difference is that we don’t have “round brackets” over here, only parentheses.

(We do have “square brackets” however.)

Re: The $440M software error at Knight Capital (2019)

#90
My small footnote to this story: we had the look on the "blind bid" to purchase the portfolio of erroneous trades on the program trading desk I worked on. Ultimately we didn't bid (thank you risk department) and it traded away to Goldman as the article correctly reports. Would've been a great trade though. I estimated it netted Goldman $2m+
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