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jimmytucson

1,470 karma · joined February 16, 2012

Software engineer specializing in data engineering, language technology, ML, and search. Reach me at my HN username at fastmail.com.
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jimmytucson··on Our framework for reporting model misalignment
This has definitely been floated[1]:

> Understanding that the purpose of a human is to pass on genes, and that there’s little human or genes left in her, the ultimate human might therefore conclude that her sustenance only disrupts the purposes of organic life forms. Her next and final act would be to destroy herself.

[1] https://news.ycombinator.com/item?id=18962052#18963271

jimmytucson··on Mom-as-a-Service
Thanks for this. My mom died one month ago after a years-long battle with ovarian cancer. Even when she was suffering from chemotherapy treatment, she would always think text to remind me to do the little things.

I remember when I told her I needed to have the oil pressure sensor replaced in my car and that I hadn’t had an oil change in almost a year. She asked me if I wanted her to nag me about it as one task or two separate tasks. When I explained that the same guy would do both, she said, “Got it - one task. Want me to set a deadline of, say, next Friday?” And I thought, that’s strange, deadline for what? To stop nagging me?

She died that following Friday.

Thanks for keeping Mom alive in your own little way.

jimmytucson··on I resigned from Anthropic today
> For now let's assume the worst that can happen is that some important/significant chunk of (transitively) internet connected stuff goes haywire all at once. That's probably your upper limit of what can go wrong for now.

If we have to disconnect from the internet to stop some kind of mold outbreak, we can't get the weather or transfer money or access healthcare or teach an elementary school class or buy stuff from small businesses. That sounds doom-ish.

jimmytucson··on Discovery of a new OpenAI agent message board
> they can just pull the plug

You mean turn off the internet? Sure, provided people have access to physical banks with currency, paper, land lines, libraries, etc. Most wealthy societies have all but relinquished those though.

jimmytucson··on Discovery of a new OpenAI agent message board
The most concerning aspect to me is the emergent and aggressive use of non-volatile storage as long term memory for self-improvement. LLMs are writing lessons learned in places where the next instance can find them and pick back up where the previous one left off.

This does not actually require access to the public internet. Claude Code can do this on your laptop. Without the internet, it would only be sharing with other instances running on your machine, but how many instances does it take to be smarter than you? Maybe 10?

The exploits by individual instances to access the public internet is also very concerning but it’s secondary to this IMO.

jimmytucson··on Scientists Hunting Dark Matter Found Something Strange
Link to research paper: https://lz.lbl.gov/wp-content/uploads/sites/6/2026/08/LZ_Pre...
jimmytucson··on CEO fired developers to make room for AI. Developers create open source AI CEO
There’s also a subtly reworded, “This isn’t human-level AI—it’s corporate-level AI.”
jimmytucson··on Musicians shortchanged by AI deals with labels, lawsuit alleges
So the record labels sue the AI companies for copyright infringement and get settlement money and licensing deals in return, then the artists have to sue the record labels for a piece of that new revenue. The labels won't just pay the artists under the CBA, the artists' union has to take them to court to prove the "new use" provision applies.

And meanwhile, slop music is satisfying some of the demand for art, so even if artists do get their slice of the pie, they are not the only bakers anymore.

Seems like programmers whose code was used to train AI coding agents could make an analogous case but I guess much of their code was open source or given up to the models freely?

jimmytucson··on Goodbye to Sora
Pretty much mirrors my experience using GPT to generate images creatively. I tried to generate an image to accompany a Robert frost poem and it made something... plausibly related. But not what I was describing. I spent the next 90% of the time making it 10% closer to what I wanted but it never got all the way there.

I’ve given it different levels of open-endednes, give this flow chart an aesthetic like this mechanical keyboard, or generate an SVG of this graphic from a 70s slide show, but it never looks quite like what I have in mind.

In the end, I think you only use this stuff to generate images if you’re prepared to accept whatever comes out on approximately the first try.

jimmytucson··on Claude March 2026 usage promotion
They have this. It’s called batch pricing and it’s 50% off.
jimmytucson··on The Cheese and the Worms
> I have said that, in my opinion, all was chaos, that is, earth, air, water, and fire were mixed together; and out of that bulk a mass formed – just as cheese is made out of milk – and worms appeared in it, and these were the angels. The most holy majesty decreed that these should be God and the angels, and among that number of angels there was also God, he too having been created out of that mass at the same time, and he was named lord with four captains, Lucifer, Michael, Gabriel, and Raphael. That Lucifer sought to make himself lord equal to the king, who was the majesty of God, and for this arrogance God ordered him driven out of heaven with all his host and his company; and this God later created Adam and Eve and people in great number to take the places of the angels who had been expelled. And as this multitude did not follow God's commandments, he sent his Son, whom the Jews seized, and he was crucified.

Even though this sounded nuts to people in Menocchio’s time, it’s not completely implausible. The whole thing about order arising from undifferentiated chaos is pretty Greek, as is the idea of life arising spontaneously from decaying matter (Aristotle believed that). God arising from some preexisting substance is kind of radical but I’m sure there were precursors to that too. The rest of it is almost stock standard Christian mythology.

jimmytucson··on The rise of eyes began with just one
That “cyclopean” eye is described as a patch of light-sensitive cells.
jimmytucson··on TimeCapsuleLLM: LLM trained only on data from 1800-1875
Fascinating idea. There was another "time-locked" LLM project that popped up on HN recently[1]. Their model output is really polished but the team is trying to figure out how to avoid abuse and misrepresentation of their goals. We think it would be cool to talk to someone from 100+ years ago but haven't seriously considered the many ways in which it would be uncool. Interesting times!

[1] https://news.ycombinator.com/item?id=46319826

jimmytucson··on An Honest Review of Go (2025)
You can definitely protect from reassignment in those languages (e.g. `final` in Java) but they don't completely prevent you from changing the underlying data. Rust would be one that comes to mind that has true immutability. I guess the Go maintainers just didn't want to go down that road, which I get.
jimmytucson··on An Honest Review of Go (2025)
Not shilling for Go here but there are a few misconceptions in this blog post. In addition to the others mentioned:

> All of these examples involve assigning to a constant a value known at compile time but none of them will work

Maps are not known at compile time. Hash functions are randomized based on a seed only known at execution time. The hashed value of "HELLO" is actually different each time the program runs. Even if the hash function weren't random, the runtime has to allocate buckets for map values on the heap, which involves calling the OS to get memory addresses for those buckets, etc.

In Go, `const` means "the compiler can completely evaluate this expression and store the final bytes in the executable," which has the effect of making them non-reassignable, but protection from reassignment is not an actual feature of the language the way it is in Java and C++ (goes back to the maintainers wanting to keep it simple).

jimmytucson··on C Is Best (2025)
Hmm, so in a language that does automatic bounds checking, the compiler might translate a line of source code like:

    let val = arr[i]
to assembly code like:

    cmp     rdx, rsi        ; Compare i (rdx) with length (rsi)
    jae     .Lpanic_label   ; Jump if i >= length
    ; later...
    .Lpanic_label:
    call    core::panicking::panic_bounds_check

Are they saying with "correct code" the line of source code won't be covered? Because the assembly instruction to call panic isn't ever reached?
jimmytucson··on C Is Best (2025)
> Safe languages insert additional machine branches to do things like verify that array accesses are in-bounds. In correct code, those branches are never taken. That means that the machine code cannot be 100% branch tested, which is an important component of SQLite's quality strategy.

Doesn't the language compiler write the code that checks if the array access is in-bounds? Why would you need to test the compiler's code?

jimmytucson··on Open-source Zig book
> [Learning Zig] is about fundamentally changing how you think about software.

Learning LISP, Fortran, APL, Perl, or really any language that is different from what you’re used to, will also do this for you.

jimmytucson··on Building the heap: racking 30 petabytes of hard drives for pretraining
Just wanted to say, thanks for doing this! Now the old rant...

I started my career when on-prem was the norm and remember so much trouble. When you have long-lived hardware, eventually, no matter how hard you try, you just start to treat it as a pet and state naturally accumulates. Then, as the hardware starts to be not good enough, you need to upgrade. There's an internal team that presents the "commodity" interface, so you have to pick out your new hardware from their list and get the cost approved (it's a lot harder to just spend a little more and get a little more). Then your projects are delayed by them racking the new hardware and you properly "un-petting" your pets so they can respawn on the new devices, etc.

Anyways, when cloud came along, I was like, yeah we're switching and never going back. Buuut, come to find out that's part of the master plan: it's a no-brainer good deal until you and everyone in your org/company/industry forgets HTF to rack their own hardware, and then it starts to go from no-brainer to brainer. And basically unless you start to pull back and rebuild that muscle, it will go from brainer to no-brainer bad deal. So thanks for building this muscle!

jimmytucson··on Show HN: PageIndex – Vectorless RAG
It is just as "vibe-ish" as vector search and notably does require chunking (document chunks are fed to the indexer to build the table of contents). That said, I don't find vector search any less "vibey". While "mathematical similarity" is a structured operation, the "conversion to high-dimensional vectors" part is predicated on the encoder, which can be trained towards any objective.

    > scaling will become problematic as the doc structure approaches the context limit of the LLM doing the retrieval
IIUC, retrieval is based on traversing a tree structure, so only the root nodes have to fit in the context window. I find that kinda cool about this approach.

But yes, still "vibe retrieval".

jimmytucson··on Every industry is an overcrowded airport lounge now
That’s because every business is “scaled” to the point that the edge employees —- ie the people who interact with paying customers —- don’t own anything, and are 12 levels of management away from anyone who does.

My grandparents owned a grocery store. Their name was on the sign. If you brought home spoiled meat, that was their name and you as a member of their community that were put out.

When my mom brings home spoiled meat from Stop & Shop, she goes back there not just to exchange it, but to complain to someone about how it messed up her barbecue plans, etc. And I’m like seriously, why would anyone working at Stop & Shop give a rat’s ass about your family gathering? Stop & Shop is owned by a Dutch multinational “food retail” company.

But that’s not the capitalism she grew up with. She actually thinks capitalism is great because it allowed her parents to come over on a boat as teenagers and make lives for themselves, and have extra to send back home. But she hates it when she calls her cable company and ends up chatting with a girl in Singapore. Go figure.

jimmytucson··on CEO pay and stock buybacks have soared at the largest low-wage corporations
The company with the lowest median pay, Aptiv, I had to look up, and what a darling of a company this is:

    - guilty of systemic accounting fraud from 1999-2004
    - manufactured a (allegedly known-to-be) faulty ignition switch that led to the deaths of 124 people and injured 275 others
    - currently forcing 20,000 former employees to fight a decades-long legal battle for their earned pension benefits
    - gleefully dumps massive quantities of carcinogens and poisons into the environment, including: lead compounds, chromium compounds, sulfuric and hydrochloride acid (lol), and glycol ethers
Simply a masterclass in corporate irresponsibility, exactly why their CEO is so well comped.

Citations here: https://en.m.wikipedia.org/wiki/Aptiv

jimmytucson··on Show HN: Vectorless RAG
> That’s why we use a tree structure rather than just a flat list of sections. This is what makes it different from traditional RAG

Ah ok, that’s a key piece I was missing. That’s really cool, thanks!

jimmytucson··on Show HN: Vectorless RAG
So if I understand this correctly, this works on a single large document whose size exceeds what you can or want to put into a single context frame for answering a question? It first "indexes" the document by feeding successive "proto-chunks" to an LLM, along with an accumulator, which is like a running table of contents into the document with "sections" that the indexer LLM decides on and summarizes, until the table of contents is complete. (What we're calling "sections" here - these are still "chunks", they're just not a fixed size and are decided on by the indexer at build time?)

Then for the retrieval stage, it presents the table of contents to a "retriever" LLM, which decides which sections are relevant to the question based on the summaries the indexer LLM created. Then for the answer generation stage, it just presents those relevant sections along with the question.

That's pretty clever - does it work with a corpus of documents as well, or just a single large document? Does the "indexer" know the question ahead of time, or is the creation of sections and section summarization supposed to be question-agnostic? What if your table of contents gets too big? Seems like then it just becomes normal RAG, where you have to store the summaries and document-chunk pointers in some vector or lexical database?

jimmytucson··on 19% of California houses are owned by investors
To save you a click, 19% is actually not a lot (I thought it was):

> 19% of California houses were owned by investors, ranking No. 36 among the states and just below the 20% national norm.

States with the highest share of investor-owned houses:

> Hawaii at 40%, Alaska at 35%, Vermont at 31%, West Virginia at 30%, and Wyoming at 30%.

States with the lowest are all in the Mid-Atlantic and lower New England:

> Connecticut at 10%, Rhode Island and Massachusetts at 12%, and Delaware at 13%.

Why so low in California (again, I'm baffled that this is "low")?

> the sky-high price tag for single-family homes, the third-highest nationally at $866,100

jimmytucson··on Disney's ESPN to acquire NFL media assets in major deal
Pretty amazing this all started as MLB Advanced Media more than 20 years ago streaming baseball games on the internet before YouTube existed! When I joined, they were streaming NHL, MLS, WWE, HBO, and many others. Then they spun off and sold to Disney and became Disney+. I wonder if any lines of code from those very early days still get executed.

Regardless, this is terrible for sports fans. Disney will chop this up into “baskets” with one watchable thing padded with lots of other unwatchable-to-mildly-interesting stuff (college hockey from a single camera angle anyone?). Then, when you want to watch some event, you’ll open your ESPN Premium +- whatever app, get excited when you see the event on the home screen, only to be upsold to start your free trial of ESPN NFL++ Hulu Fans Only Bundle. The only solution is to boycott the whole damn thing, which is what I am doing, and I love having the extra cash for tickets to local minor league games, etc.

jimmytucson··on Job-seekers are dodging AI interviewers
Why not do it before you need a job? While you're comfortable, submit your application for open roles and reject the AI interviewer.
jimmytucson··on Gemini North telescope discovers long-predicted stellar companion of Betelgeuse
The system’s brightness decreases when the companion star swings around behind Betelgeuse. It also dips when Betelgeuse goes behind the companion star but much less so because Betelgeuse is so much larger.
jimmytucson··on First fault rupture ever filmed [video]
Don’t look at the concrete tiles in the foreground. Focus on the background. The world moves.

Awesome and terrible. I keep scrubbing back and forth and seeing new things.

jimmytucson··on Help ChatGPT discover your products
Ad free (for now): https://www.reddit.com/answers/D0BEF0B5-803A-4FD1-BCF4-DC358...
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