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Posted by henrygarner 11 hours ago

We found an undocumented bug in the Apollo 11 guidance computer code(www.juxt.pro)
341 points | 172 commentspage 2
chrisjj 8 hours ago|
> The specs were derived from the code itself

Oh dear. I strongly suggest this author look specification up in a dictionary.

perching_aix 8 hours ago|
It's (what they're describing is) just reverse engineering. That's what reverse engineering is.
chrisjj 6 hours ago||
Fortunately reverse engineering too is in the dictionary - to help anyone mistaking it for spec generation.
perching_aix 4 hours ago|||
Implying that I did make such mistake, which I did not, unless you're willfully taking me overly literal.

Nor did they make any mistakes when they described how they produced a specification, (and indeed, that it is a specification) despite your insinuation otherwise, for a similar reason.

Maybe instead of pointing towards dictionaries, stop pretending that you lack reading comprehension, and get off of your high horse please.

bsoles 2 hours ago||
Another CTO "published" an AI slop to get attention to their vibe-coded company that will disappear in two years. Tell me something new...
totalmarkdown 6 hours ago||
is this bug the reason why the toilet malfunctioned?
dmoy 4 hours ago|
I don't think apollo 11's toilet malfunctioned, it was just not very good. Everything smelled like poop mixed with chemicals, and that was by design.
kmeisthax 6 hours ago||
> Rust’s ownership system makes lock leaks a compile-time error.

Rust specifically does not forbid deadlocks, including deadlocks caused by resource leaks. There are many ways in safe Rust to deliberately leak memory - either by creating reference count cycles, or the explicit .leak() methods on various memory-allocating structures in std. It's also not entirely useless to do this - if you want an &'static from heap memory, Box.leak() does exactly that.

Now, that being said, actually writing code to hold a LockGuard forever is difficult, but that's mainly because the Rust type system is incomplete in ways that primarily inconvenience programmers but don't compromise the safety or meaning of programs. The borrow checker runs separately from type checking, so there's no way to represent a type that both owns and holds a lock at the same time. Only stacks and async types, both generated by compiler magic, can own a LockGuard. You would have to spawn a thread and have it hold the lock and loop indefinitely[0].

[0] Panicking in the thread does not deadlock the lock. Rust's std locks are designed to mark themselves as poisoned if a LockGuard is unwound by a panic, and any attempt to lock them will yield an error instead of deadlocking. You can, of course, clear the poison condition in safe Rust if you are willing to recover from potentially inconsistent data half-written by a panicked thread. Most people just unwrap the lock error, though.

wg0 9 hours ago||
Someone please amend the title and add "using claude code" because that's customary nowadays.
chrisjj 7 hours ago|
Also add "AI can make mistakes". Thank you.
sgt 7 hours ago||
Thank you for your attention to this matter.
esafak 6 hours ago||
An application of their specification language, https://juxt.github.io/allium/

It seems the difference between this and conventional specification languages is that Allium's specs are in natural language, and enforcement is by LLM. This places it in a middle ground between unstructured plan files, and formal specification languages. I can see this as a low friction way to improve code quality.

iJohnDoe 7 hours ago||
Fascinating read. Well done. Everyone involved in the Apollo program was amazing and had many unsung heroes.
yodon 9 hours ago||
This is so insightfully and powerfully written I had literal chills running down my spine by the end.

What a horrible world we live in where the author of great writing like this has to sit and be accused of "being AI slop" simply because they use grammar and rhetoric well.

dotancohen 9 hours ago|
I was completely riveted the whole read. The description of Collins' dilemma is the first time I've seen an actual real world scenario described that might cause him to return to Earth alone.

If an LLM wrote that, then I no longer oppose LLM art.

breakingcups 8 hours ago||
I thought that was the least likeable part of the article. They speculated wildly, somehow making the leap that a trained astronaut would not resort to a computer reset if the problems persisted to weave the narrative that this bug was super-duper-serious indeed. They didn't need that and it weakened the presentation.
MeteorMarc 8 hours ago|
Are there any consequences for the Artemis 2 mission (ironic)?