A lot of national defense stuff is a de facto "government sanctioned monopoly" and this is certainly the same flavor. Market forces are different if the industry is perceived to be vital to continued sovereignty.
Margaret Hamilton was 1,000% a hacker. She basically pioneered the foundations of asynchronous code and was one of the first people to work on rockets at a time when software engineering was in its infancy.
I'm well aware of her impressive achievements. But she had to share computing resources with the original "hackers", the ones who gave us the word, and I don't think she was very fond of them, or of the hacking approach in general; her ingenuity was great but not especially playful. So I don't think she would want to be memorialized here.
I don't particularly care what you think about what she would think about the definition of a word used in the site name. She's a person worth remembering and honoring.
Let your weird fixation on the word stop you from honoring her here if you want. It won't stop me.
If you want to honor her memory, as I do, I suggest you think about what she would have wanted, which entails, at a minimum, caring about what well-informed people tell you about her life's work and beliefs.
if you want I can troll through submissions to get a bunch of these but here's one I saw yesterday https://continuum-app.xyz
see that little "Built for equity compensation" pill with the green dot? Those dots usually denote some kind of status (like things are up/down/enabled/disabled). By default nearly every LLM website seems to be dark mode with that dang status pill. once you notice it you will see it everywhere.
Lmao I had to axe one of those status pills from an LLM build of an internal tool. Connected to literally nothing too btw, no attempt to check the actual status of the backend made, it would stay "connected" regardless.
> Customers can be reassured that the Facewatch system has a 99.98% accuracy rate, and every match is reviewed by a trained manager.
That's not "reassuring" at all. If Sainsbury's gets, say, 10M customers per week, then that means 2,000 people per week are being falsely accused.
Likewise, if you visit Sainsbury's twice a week for groceries, the odds are favorable that at some point in your life you will be falsely accused, even with a 99.98% accuracy rate.
As I understand it, it's a combination of things: aircraft reports, atmospheric motion vectors (e.g. a cloud doesn't have any propulsion, so if a cloud moves 30 km in an hour, you have learned something about the wind), Doppler wind lidar, and satellite measurements.
The numerical predictions of weather models often have many vertical components as well, so solving it for ground level also requires extending the forecast to the air, depending on the model.
To predict anything on the ground, you have to predict air temperature, humidity, wind speed and direction etc. for the entire troposphere. The output of the models in altitude are as relevant to the meteorologists as the output on the ground for manual expert analysis.
> Jane Street has generated more than $40bn in net trading revenues in the year to Friday, even accounting for the July loss, which exceeds its entire haul for 2025, according to one of the people familiar with the matter.
This would make JS one of the most profitable trading firms of all time even with the loss.
But then what does it mean when the FT writes that that "revenue" number already accounts for the 15 billion losses? That the FT doesn't use these terms correctly either, and we can't really know what its reporting means?
That’s the correct usage. Revenue includes gains and losses. Profit will take that number and subtract out the operational costs (salaries, market data subs, etc).
It’s trading profit. No one is counting their gains from a trade while including their rent into it.
It’s a much easier to understand metric when you are discussing losses on a trade. No one is calculating losses including salaries.
It means Jane Street is still highly profitable in trades this year despite making a bad bet. If they have overhead that eclipses that, that is an entirely different metric.
Are they "trading" or "high-frequency-ripping-off-retail-investors"?
It's easy to make paper billions with synthetic shares and infinite deadline extensions for settlement. I'm old and still remember when Ken Griffin was lauded a clever person before he got caught with his hands in the GME mayo jar..
Liquidity providers like Jane Street, Citadel, et al make money on the spread. They also buy order flows from integrators, and retail investor order flows are now a product.
i.e. retail investor → brokerage platform → clearing/execution infrastructure → Jane Street → payment back toward the brokerage side of the chain.
Who captures the economic value created by retail order flow?
Jane Street.
In an ideal market, this product line shouldn't exist. Institutional investors should not be making money on the activity of retail investors.
What incentives determine where that flow is sent, and would investors receive better execution if their orders were exposed to genuinely competitive price formation rather than privately internalised by a concentrated group of wholesalers?
The regulators should be squashing any HFT related or retail order flow, but it's so opaque _by design_ that getting policymakers, or the general public, to understand that retail investors are paying some portion of tax on their $20T USD annual trades to these companies.
Granted, these order flows _sometimes_ work the other way -- and retail users get a better deal on a trade.. But would you really expect the market to be worth what it is, if that was the case less more often than not?
There is a clear and obvious conflict: the broker is supposed to seek the best execution for the customer while potentially being paid by the firm receiving that customer’s order. How can that be, when the broker's in bed with the liquidity providers?
PFOF and HFT are distinct concepts, but they are widely conflated in this thread. I don't agree that PFOF is inherently bad, but even if it were: it is not a valid criticism of HFT.
HFT raises pricing for retail traders by allowing front running of trades and makes the market less competitive overall for those without the infrastructure to do so. This isn’t even in question.
It's very much in question. As much as I hate to admit that since I do not like the concept of HFT existing as it's not providing very much value to society (imo) compared to the money made. The intellectual power behind this stuff would be much better put to use for something productive.
It likely lowers the transaction costs due to adding liquidity and narrowing bid/ask spreads for small retail orders.
But indirectly it likely raises costs for institutional investors like pension funds and large ETF managers making giant block trades on behalf their beneficiaries.
So tldr; Probably fractionally better pricing for your $5k GOOG trade, fractionally worse for your VOO holdings over the long term.
Does it really hurt institutional traders? How? Is it based on the idea that they can’t get the retail spreads? Because there is no world where they would have ever gotten them. A market maker would loose money doing that.
I'm certainly no expert whatsoever. This is just my understanding from talking with a few folks I consider quite smart who work in the space. Some working for HFT firms, some elsewhere. Also reading on the topic over the years.
There does seem to at least be some evidence that HFT firms decrease retail spreads overall. Either way, my main point being made is that negative impact to retail traders is very much in question.
Market makers are simply an artifact due to how shares are traded based on limitations that existed before computers. The aren’t some inherent aspect of having a stock market.
The money isn’t coming from thin air. If N people trade a a finite set of shares back and forth every day the only way to extract money from that set of people is for them to lose money.
Yeah, the stock market may be positive sum over the long-term, but it's certainly zero sum over the millisecond-term. Whether it's "retail" or "institutional" that is paying for HFT profits, it's all retail in the end.
The millisecond-term zero sum game is part of what allows for a positive sum long term. For example, zero fee trading was pioneered by Robinhood and only possible because of payment for order flow, and as a result it's virtually unheard of now for retail to be paying per transaction. Now more retail investors can participate and everyone benefits. You can also point to lower spreads and faster execution as direct benefits.
No one? Mutual funds have managed to attract $33 trillion trading once a day. The demand for millisecond-level trading is almost entirely from a very small group of firms profiting from it.
And they are steadily losing new investment dollars to ETFs, which trade interday. I don't think interday trading is why ETFs are more attractive to all or most investors, but a 0.000001% (or whatever) cost advantage just falls below the noise floor. It isn't worth any other tradeoff.
That's true, we don't want it to do that, we want it to kill these parasitic entities. Much like one doesn't swat a mosquito because one will truly miss the amount of blood she's taking.
> it's certainly zero sum over the millisecond-term.
Why do you think market-making is zero sum? Providing liquidity has value and market makers are compensated for that. (Milliseconds of liquidity being appropriately compensated with fractions of pennies.)
Again, the costs are de minimis and they're just competing with other, slower market makers to provide the same service at lower costs and faster speeds. Who cares? Retail investors, rationally, should not care about this at all.
If the costs where actually de minimis nobody would be fighting on those timescales, instead the costs paid by the market is the full operating budget of these companies plus their profits plus their negative externalities which combined ends up being significant.
Ultimately the primping value of markets is in information gathering and by flooding the market with trades based on ms timescales you’re masking important signals with meaningless white noise.
> trade something like $500B/day of volume or like $125T/year
Trade volume is meaningless in the face of HFT. The very actions you’re defending prove the numbers you just presented have zero relevance and could increase by 100x with zero benefit to anyone.
However step back a second. Quoting a number roughly equivalent to global GDP is frankly silly here, but it’s an easy enough mistake to make when your basic premise is inherently flawed.
> No. Combined, it is still de minimis. US equity markets alone trade something like $500B/day of volume or like $125T/year.
If that was what you where trying to describe the second sentence is unconnected to the first.
> half a penny per share traded
That’s far from de minimis. Rebalancing a portfolio now becomes quite expensive over a lifetime. You lose 0.5c selling and 0.5c buying, on say a 10$ stock and that’s 0.1% per transaction, and you don’t rebalance once.
Isn’t Ken Griffin still considered very clever? Citadel is one of the most successful hedge funds of the is era and has largely accelerated since 2020.
There's this famous line item which is called something like "securities sold but not yet purchased", e.g. with their market maker privilege Citadel can create infinite synthetic shares out of thin air to facilitate that a trade happens, but they have abused this privilege on a very large scale which has created an idiosyncratic risk to all stock market investors.
Due to regulatory capture of the SEC this risk has not materialized in an overall market crash, but they have done numerous accounting shenanigans and deadline extensions to give Citadel more room to breathe.
This statement doesn't go far enough given Elon's direct and hands-on involvement with DOGE and the 2024 elections. Very few of the richest people of the world are personally entangled in meddling with government agencies directly, for example.
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