skysight-inc/HackerNews huggingface dataset:
I'm sorry, but this seems a bit of a lazy question.

There are many large-scale deployments of MongoDB - a simple Google search will yield you results.

Off the top of my head - FourSquare, Stripe, ServerDensity, eBay (non-site) etc.

MongoDB (the company) also uses it for MMS - their cloud-based monitoring system, which probably handles hundreds of thousands of metrics every second from tens of thousands of hosts.

So yes, there is a lot of FUD about "it doesn't scale" etc.

Most of the FUD seems to originate from people not reading the manual, and completely misconfiguring things, and wondering why it doesn't work.

To be fair, most competing products (Riak, Couch etc.) will scale enough for most people. So this is sort of a red herring. (And by the point that you are as big as FourSquare, the assumption is you'll probably hire engineers who will read the manual =) ).

So the decision boils down to other things - how easy is the query language, do you need GeoJSON support, do you need aggregations, how mature is the overall ecosystem etc.

And that's why people are picking MongoDB - not really the WOAH, LOOK AT THE OPS PER SECOND!.
Fight against false copyright claims goes to Capitol Hill
Well, you can't suspect that when you're just reading that convo without prior information!
Surely this whole mess can be fixed with a 5 minute UI change - reword the copy and add a checkbox to do/don't take a snapshot (default to checked (take a snapshot)).
Sounds like you can get people easily arrested by mailing them child porn without a return address and anonymously tiping off police.

Kind of like destroying someone's reputation via sybil attacks, on an app like lulu or yelp or whatever. The NSA had slides on how fake victims could write blogs about being raped or mistreated or whatever.
There is no "cut in front of you" message in FIX or OUCH. Most exchanges use price/time priority - if someone "cuts in front of you" it means they offered $50.01.

Or maybe "cuts in front of you" means you wanted to buy the stock at $50, but you didn't actually place the order until the last minute because you wanted to play a speed game (and lost).
I'm missing something. How does this mitigate the race for first in on the level?
I think you're being a little unfair to kriptonic here, and perhaps being a little confused about causation. You're assuming he's failing because he's a negative person. I would say it's much more likely his negativity is a result of being burned out from too much work and not enough sleep.

Burnout is a good thing. Your body is basically telling you that you are working too hard at something that is not achieving results, and it's time for a change.

kriptonic: I would recommend leaving your side projects on the back-burner for a while. Just work on your day-job, and catch up on your sleep and maybe take a vacation. Once you've taken a break, start thinking about your projects and you might come up with a new direction.

Just because you think your idea is good doesn't mean it will be successful. It also doesn't necessarily have much to do with being good at business. You just need to come up with something that other people want to use.
You said it much better than I could. I also think their intimations that mathematicians will use computers to ensure their theorems are correct will not come to fruition, though they are selling it as a huge advantage.
It is worth drawing a distinction between that which requires a coercive third party like government to enforce (e.g., intellectual property) and that which does not require such a thing (defending property).

The distinction is a direct consequence of the fact that intellectual property isn't actually property. (Because it is not scarce.)
Swatch CEO won’t play ball with Apple, disapproves smart watch concept
Have you honestly never seen someone park in a handicapped parking spot?
Class War with a Smiley Face
Wouldn't the increase in share price and payment of quarterly dividends count as a reward? [1]

[1] http://finance.yahoo.com/q/bc?s=MSFT+Basic+Chart
No, his issue is with HFT companies using fragmentation to trade risk free and skim obscene profits off the top from institutions that make these large trades. From the 60 minutes piece, one hedge fund estimated that this kind of thing was costing them $300m/yr.
> and neither is anyone else

who is living in the United States.
There are a many of news articles and youtube videos which present HFT as a bad thing.

Since large orders are filled by different markets, anyone who has studied the mechanisms via which these orders are full-filled can theoretically arrive at a strategy that might be profitable.
Overtime, more and more people will learn these things and it will no longer be a profitable strategy to implement - this is sort of like the "January Effect" described in the book named intelligent investor.

I don't understand why HFT has to be blamed for a difference in prices across multiple markets. I read somewhere that REGNMS caused market fragmentation and HFT traders spend time studying the current markets and identify inefficiencies that can be used to make profitable trades.

This Reuters article is like an advertisement for the IEX trading platform. IEX figured out a certain way to beat the other algorithms and they told Reuters about it. Now that everyone knows it, I think, pretty soon other algorithm developers will modify their implementations.

Overall, I think that HFT is basically algorithmic trading, but which needs more investment (for renting/buying server/connectivity) and more time/interest (for studying and understanding the order placement/fulfilment mechanisms involved).
I don't know of a HN type site but seekingalpha.com is quite good for info.

edit - I had a look to see if they had mentioned this article - not as far as I can tell but there was a similar thing from a year back. Discussion a bit lame but better than nothing IMHO
http://seekingalpha.com/instablog/5760541-tales-from-the-fut...
I don't know, those services are probably good, but Bitcoin works perfectly and we don't mind the volatility, and I kind of enjoy it.

There are plenty of minor reasons to prefer Bitcoin, like how nobody can prevent you from accessing your funds for something like "suspicious activity".

But there are a some bigger reasons - if you're good with your security, you don't have to do things like check another statement every month to see if someone stole your account information.
To give you an idea on how HFT has blown up since 2007:
http://www.technologyreview.com/sites/default/files/legacy/d...

Context: http://www.technologyreview.com/view/428756/watch-high-speed...
Its not going to work without porn.
Up-vote this, 1000x.

Exercise changed my life, not long ago. :)
How dare you use facts to back up your case in a HFT forum discussion?
Google hiked wages to combat Fb after fb refused to join hiring cartel
HFT is manipulating the pricing so that it is no longer worth it for you to buy it, therefore fleecing you of the profits you would have made if they weren't there.

Of course, this is not illegal (it's like any other type of trading, pushing up the value so it goes beyond what you're willing to pay) - but it's achieved by using robots in such a way that normal humans can't hope to compete.

Of course, you can build your own robots (ie your own HFT software) to take advantage of the weaknesses of existing HFT programs, but if you can do this, you would be working at an ibank as a quant of some kind.
> It drops to $49.99, and someone cuts in front of you in line

Um, how do they do that, exactly? The major equity exchanges are all FIFO on every tick price. If you put a limit order in for $49.99 before somebody else, and an offer crosses your bid, you'll get filled before they do, period.
Am I the only one who got an ad for Chevrolet? Pretty awesome that GM helped pay for the segment.

(Also for Viagra... not sure about that one.)
My personal view on this subject is that while I don't believe in a god its still possible that there might be one.

Saying there is no god is kind of ignorant unless I know 100% for a fact there isn't one
This article reminded me of the "four agreements": "Be impeccable with your word. Don't take anything personally. Don't make assumptions. Always do your best." Not lying falling under the first.
A rule like this would cause every market marker to set their bid/ask spread wide enough to cover the risk of the typical adverse price move which could occur over 60 seconds.
Because this: http://static.businessinsider.com/image/519538866bb3f78a6900...

Do you see Windows' slice of the pie getting larger anytime soon?
Your pot of boiling water prediction is based on past experience, not modeling of the smaller scale system. Climate science is akin to modeling turbulent flow inside the pot to predict when the pot will boil.
Wouldn't an encrypted volume be essentially random data to anyone who doesn't have the key? So all you'd need to do is scrub any traces of the key itself.
Its amazing how similar this line of reasoning sounds to the development of democracy mode in Twitch Plays Pokemon.
The need for an open sum tends to be vanishingly rare in my experience.
I'm a millennial and I own a car. But I will sell it soon.

It didn't make me happy.

I don't have to concentrate when I'm using public transport AND I'm allowed to use it even when I'm intoxicated. Also it's much cheaper than a car.
Yet, I for the life of me cannot describe how they do this. Can you write out the basic trade that HFT companies use to get all this risk free profit?
What is missing from the discussion here is that where domain knowledge is less important. For example, almost every widget system I have ever looked at uses class inheritance because it makes it relatively easy to manage consistent interfaces across classes. This is true of GTK, wxwidgets, and many more.

It is true that the natural world doesn't necessarily admit of perfect neat classifications generally, much less trees. However, when we are talking about purely engineered solutions, the same arguments don't apply in the same way.

Here's an example. In LedgerSMB 1.4, we use (shallow) class inheritance in a reporting framework. It works, and works well. Reports inherit an abstract class with lots of hooks for customization but a lot of defaults.

In future versions we will likely be moving away from an inheritance-based approach, not because of the arguments here or the maintenance issues (which will crop up any time you rely on external components) but because we think we can create clearer code by moving from a class/inheritance approach to a DSL approach.

I am not sure that class contracts and DSL syntax contracts are necessarily any different from a maintenance perspective other than the fact that the latter strikes me as resulting in clearer code.
Launched a simple MVP. Private hosted GitLab githost.io
Can you actually describe this market manipulation?
CoffeeScript seems to be an efficient alternative to plain Javascript. The fact is you can't avoid seeing Javascript completely. Just try debugging in Chrome or any other browsers built-in debugger and you'll know what I mean.
Infrastructure has been surprisingly important to a few innovations in the past: Edison didn't just invent a commercially viable light bulb... he also built the power stations (which of course didn't exist before they were needed); Mr Birdseye didn't just freeze fish... he (actually the company that bought him out) established freezers in supermarkets (which of course didn't exist before they were needed).
Anybody who thinks "we" (I guess North America?) just had a record cold winter aren't just ignorant of climate science, they aren't even reading xkcd.

http://xkcd.com/1321/

How... uncultured.
Be like Musk: don't give up til you've failed three times... and given it one more try.
What about us who live in developing nations and get paid less than USD1000 per month working as a dev? Saving money is hard over here.
> skim obscene profits off the top from institutions that make these large trades

It's not like in the pre-HFT days market makers would just obligingly fill institutions for whatever volume trades they wanted to execute, regardless of how ham-handedly they broadcast their intent into the market. Any estimate of "costs" to institutions from HFT needs to be measured not against some Platonic ideal scenario where market makers earn no profits, but rather against the old specialist system that it replaced. In which case I suspect the costs would come out quite a bit on the negative side of $0.

There are some practices in HFT like paying for privileged newswire access that could use some reform, but the best solution to this fragmentation issue is for large institutions to stop sending out their orders like it's the year 1995.
Sorry to hear about your situation. For what it's worth, my advice:

Stop trying to build a startup. Build a business instead. A bootstrapped, makes cash today business. Maybe it's a consultancy specializing in bank software or maybe it's something else that you have expertise in, but stop trying to build an all or nothing startup.
I'm planning to sell my car. Biking makes me a lot happier than driving a BMW.
> When they do, most pain points caused by NATs will go away, and that's not webrtc specific.

This is a naive statement since it assumes IPv6 support amongst the clients. At least here in the US, such support is fairly minuscule.
For those of you who want to understand this topic better (i.e., a lot of the people spinning conspiracy theories), you might want to learn the basic mechanics of HFT. I wrote a tutorial on the topic a couple of years ago, might be helpful:

http://www.chrisstucchio.com/blog/2012/hft_apology.html

http://www.chrisstucchio.com/blog/2012/hft_apology2.html
A Night at Hacker News Kansai in Japan
The Internet Is Here. Why Are We Still Making Decisions Like It’s The 1700s?
From the HN Guidelines link at the bottom of the page:

"Please don't post on HN to ask or tell us something (e.g. to ask us questions about Y Combinator, or to ask or complain about moderation). If you want to say something to us, please send it to info@ycombinator.com."
The approach touted by the 60Minutes piece, the coop-like IEX market that aims to equalize participant lags, is one obvious countermeasure.

Another promising tactic could be the "Frequent Batch Auctions" as described in the paper referenced in this blog post:

http://johnhcochrane.blogspot.com/2014/02/budish-cramton-and...

Direct paper link: http://faculty.chicagobooth.edu/eric.budish/research/HFT-Fre...

Paper abstract:

We argue that the continuous limit order book is a flawed market design and propose that financial exchanges instead use frequent batch auctions: uniform-price sealed-bid double auctions conducted at frequent but discrete time intervals, e.g., every 1 second. Our argument has four parts. First, we use millisecond-level direct-feed data from exchanges to show that the continuous limit order book market design does not really “work” in continuous time: market correlations completely break down at high-frequency time horizons. Second, we show that this correlation breakdown creates frequent technical arbitrage opportunities, available to whomever is fastest, which in turn creates an arms race to exploit such opportunities. Third, we develop a simple new theory model motivated by these empirical facts. The model shows that the arms race is not only socially wasteful – a prisoner’s dilemma built directly into the market design – but moreover that its cost is ultimately borne by investors via wider spreads and thinner markets. Last, we show that frequent batch auctions eliminate the arms race, both because they reduce the value of tiny speed advantages and because they transform competition on speed into competition on price. Consequently, frequent batch auctions lead to narrower spreads, deeper markets, and increased social welfare.
What? I'm not assuming anything. All I did was post a link to Elon Musk's own words.
You've responded well -- all you can hope is that people understand.
Here's my 2 Cents...

First of all, DO NOT quit your job unless your new business is making money. You know what's worse than working a job you hate? Not having any money at all.

Secondly, stop trying to start the process with an idea. The best way to come up with a solid business idea is to pick a market (preferably one you know something about) and learn as much as you can about it. Observe what people are saying. Write down what people are complaining about. Get to know them inside and out. Once you've done the market research, THEN brainstorm ideas based on that research. Start small. Build a landing page with an email submit and shop the link around to your market. If they bite (which they should if you did your research properly), then work on building out the product.

All that work should cost you nothing more than time and hosting/design. Save that $5000 for when you'll really need it—after your product has been validated and you have interest/pre-orders.

Good luck!!
Outkast, in charts
"I do everything I can to make sure she's happy."

That's the wrong way around. Do everything to make sure you are happy, with or without her. It's up to her if she wants to be happy with you.
If you think that today's stock market is like 1999, then you weren't around to see the utter madness that was the stock market during the dot com days.

It was sheer insanity how crazy stocks were being bid up. Absolutely valueless companies were bid up 10x by day traders. There was zero sense of fundamentals, and fraud was rampant everywhere. The company I worked for went bankrupt due to financial fraud and many of my coworkers lost hundreds of thousands to millions of dollars.

Right now, we have essentially 2 companies, Google and Facebook, that are throwing billions upon billions of dollars worth of shareholder money to seemingly stupid ideas. And while I'm sure there's still plenty of fraud, you don't have anywhere near the same level of fraud as you did back during the dotcom days. I truly do believe that most companies and more especially CEOs are a lot more cognizant that they will go to jail for financial fraud if they step over the line, so they are a lot cleaner than they were 15 years ago, for the most part.
I guess it’s not about Business class or working class. Sometime people get overwhelmed by an idea, and this idea has its inception from what other people are doing. This makes you look what you are doing is not good. Business, Job, Status, Money etc. it’s all work and just a small part of life (Life has many more aspect). If something does not work for you, then let it go. Start new, which bring backs balance to your life. By starting new I mean not only work, if your work does not bring money then switch (there is no shame); if your current job gives you a lot money but now time to spend with your loved you are still doing a stupid thing; if your individualist character don't let you pursue grouping (family/relation), bring a change in you (how much you devote to life that relation)... It’s all about balance. When you are standing at such a point in life, people can just give you advice; it’s just YOU who can help YOURSELF. No work is big or small, real status is being a good person…..etc.…

So my friend, let it go, start with something which will --> work for you <-- and which will get you what ever really matter for you (your Girlfriend, time, family). It's your time which is getting consumed and time is the most precious thing.

It’s my recent realization after I feel in love (with my family, a girl, and me :D )!!!

Balance is the keyword!!I guess :)
The article is interesting, but the writer's main point seems to be lacking much evidence. The normally volatile Bitcoin price actually remained flat for days after the IRS announcement - because it wasn't a surprise.

The article briefly mentions a much more plausible reason for the sizable price drop, which occurred later: China cracking down on bank to exchange deposits. The writer just sort of handwaves it away.

There's no evidence that the IRS ruling pushed the price down, in fact there's plenty of evidence that it did not: the fact that the price did not move.

Meanwhile, there's plenty of evidence that China's action did affect the price. As soon as rumors began to spread, trades on the Chinese exchanges were happening at prices far below those on outside exchanges.

The Chinese exchanges led the market down every step of the way. (Naturally a price fall in China soon began to pull down prices everywhere, due to arbitrage, and an understanding that the probable withdrawal of Chinese money was very bad news for anyone speculating on the short term price).

Chart showing price remaining flat for 2 days following the IRS announcement on 3/25, and then falling sharply on firm news from China (Caixin report 3/27):
http://bitcoincharts.com/charts/bitstampUSD#rg60zczsg2014-03...
Unable to download free book from Google play without credit card
The criticism I've heard of this is that HFT only extracts at most 2-4 billion from the economy each year. Is that the case? If so, I find the arguments against to be kind of trivial.
Sure, but if't it's sensitive data, the extra couple minutes is probably worthwhile.
Or any other country adopting similar rules.
The bigger story of HFT is that it enables the big banks to manipulate the stock market. Because they know all market orders before they are executed, they are able to cancel all bids and offers before it is possible for anyone to hit or take them. They can also put up huge orders on the bid or offer to make a stock look weak or strong in the short run, knowing there is no risk of being executed. If they see another order come in they can just cancel their order.
The most criminal advantage HFT gives them is that they can front run orders. Let's say for example that Fidelity calls Goldman Sachs and says they want to buy 1 million shares of Tesla. This information is priceless as Tesla stock is guaranteed to fly higher on this trade. Acting on this information is the most blatant form of insider trading that exists. However, somehow the big banks can create programs that do exactly this. Whenever they see a huge influx of buy or sell volume they can quickly jump in front and close out the transaction a few seconds later for a huge profit.
China is to startups, what Australia is to evolution. They are both these amazing walled ecosystems that develop completely independent forms of life (digital or otherwise.)

What confuses me is that the Chinese do this in plain sight and yet the American startup ecosystem doesn't seem to give them much mention. I hardly even seen TechCrunch or Pando talking about Chinese startups, while at the same time they are willing to talk about London, Berlin and Tel Aviv startups. I've always wondered if this was because of some latent racism, or because of the foreigness of the Chinese characters.

Either way, it's interesting to think that parts of the forefront of innovation isn't being reported (this story aside), and that there's a whole world of technology culture that's developing independently in China in part because of the totalitarian political regime.

I, for one, think that digital currencies are going to explode in China - the Chinese love to gamble on things like this, and the Yuan is a joke. I believe that it might just be the most opaque currency in the world. (But I don't know much about all the other ones that are in the running. Nor do I know how much the other currencies are lying.)
I really like your idea of allowing sub-penny ticks in the highly liquid stocks as a way of tilting algo trading away from the latency arms race. Unfortunately, it probably runs too counter to the uninformed "no one should be trading to make $0.01 per transaction!" popular perspective for the SEC & exchanges to implement it.