Sweden's cashless society is no longer a utopia - <AUTHOR> https://www.weforum.org/agenda/2018/11/sweden-cashless-society-is-no-longer-a-utopia/ <comment><USER2> I'm a Norwegian who went to a Swedish music festival last summer.

I couldn't pay for a lot of things there, since the booths only accepted Swish (the only relevant Swedish mobile payment solution, it's a de facto monopoly). I couldn't sign up and use Swish on my phone, since it only accepts Swedish bank accounts. I couldn't borrow money from my Swedish friends either, since they didn't have cash (and it mostly wasn't accepted at the festival anyway).

When I could get someone to pay for me directly, transferring the money back to them was hard (since the festival didn't have any ATMs), so I had to go through the whole burdensome SWIFT procedure with getting their bank account number, their full name and address, their bank info, IBAN number of their bank etc, so I could send the money back when I got home to Norway.

Utopia my ass.

<comment><USER3> That's festival payment done wrong, but cashless can be really great at festivals.

In Denmark we have a festival called Skanderborg festival, and they build both your ticket and your cashless payment into the festival bracelet.

You use the bracelet to pay everywhere, and you can add money to it a range of payment methods, from using a visa or similar in their app, to visiting one of the cash places where you can use an atm and then add funds to your bracelet.

It's easily the best payment experience I've ever had at a festival.

<comment><USER4> The best payment experience I've had is cash. I pay for what I need and when I leave the festival I can still use my "credits" hassle free anywhere I like.

<comment><USER5> The trouble with cash is that you cannot really control high-school dropouts to charge $10 for a $2 beer without skimming a bit on the side. Hence this whole "here's some fake money that only works here" BS.

<comment><USER6> Just do an incorrect inventory. Some venues let workers do inventory and reporting. They are charging for the cup itself and that is how they determine sales. If a stack of cups disappears, there is no reconciliation.

Music venues have some interesting procedures, Alpine valley allows under an oz of weed to be brought in. They have college girls carrying backpacks with 40k in cash. There is an off duty cop directly behind though.

<comment><USER7> Can you elaborate on that second paragraph? I don't understand how those things are related to each other.

Why do they allow weed to be brought in? Why do they have college girls carrying cash in a backpack? Why so much cash? Why is there an off-duty cop following her around? Isn't an off-duty cop just an ordinary member of the public? If a cop is required shouldn't it be an _on_ -duty cop? If it's somehow a trap to catch drug dealers, how is it meant to work? Why do they limit the amount of weed? And why are they trying to catch drug dealers at all?

<comment><USER8> Back in HS I worked at an amusement park for a summer. On a busy night, if I closed the booth, I'd be walking out the park's employee exit around 2am, through a somewhat busy and not-very-well-lit public area of the parking lot, and across to the admin offices with 30k+ in a plastic bag. That was not an uncommon amount for most of the non-token booths, and having 16-18 year old kids carrying it out of the park to the admin building was also common, since that was most of the park's work force.

I'd guess the "college girls carrying 40k in cash in a backpack" were employees carrying cash out from whatever business/booth they were running and taking it to their bank or head office or whatnot, and the "off-duty" cop behind them was there acting as a security guard; since that's a somewhat common side gig for cops, and in may places, they're still given all the power and authority an "on duty" cop has.

I don't get the connection to the weed (legal or otherwise, it has never been an interest of mine), but perhaps it explains the other bit.

</comment></comment></comment></comment></comment></comment></comment><comment><USER9> A society without cash is a society in which every person has no choice but to get the permission of someone they don't know and will never meet each and every time they seek to obtain food, water, shelter, or transportation, and that permission can be revoked instantly, silently, and invisibly at any time.

<comment><USER10> Want to share about my experience about the "permission" part.

I once travelled to Beijing and had dinner in a fancy dumpling restaurant. When I went to pay the bill, my European bank instantly flagged the transaction and blocked my card from further use. I had no idea what happened until I called the bank later that evening (had to wait until they opened). So yeah, what you said happened to me - revoked instantly, silently, and invisibly at the most unexpected time. And even though I didn't do anything wrong.

<comment><USER11> That's anti-fraud to stop someone from stealing your card and using it elsewhere. You can usually pre-empt that by informing the bank of travel.

<comment><USER12> Anti-fraud is done for the bank's benefit, with little incentive to prevent false positives. In my own experience, 100% of my blocked transactions have been false over the last few years (since I moved out of the US, where fraud is more rampant). It's extremely annoying - it's my money, but I can't use it because the bank is being overly conservative.

<comment><USER13> 100% of fraudulent transactions have gone through silently on my card. Despite the fact that many times my bank has sent me an SMS querying whether something was kosher. Doubly perplexing because they were OS hotel and airline charges, I had a stream of local transactions (fuel, supermarket), I very rarely pay hotels directly, and the bank makes it easy to tell them you are going OS.

After much drama they refunded me. The hotel didn't seem to even care -- presumably they were not getting a huge charge back. IDK if it was a 'card not present' or what. They couldn't even tell me the name of the person using my card -- privacy rules.

</comment></comment></comment></comment></comment><comment><USER14> No mention about the privacy implications of having every transaction tracked? We're already at a point where pretty much every transaction is tracked and a cashless society makes being tracked a requirement to function in society. Is privacy even a topic of discussion with governments looking to go cashless?

I still try and pay with cash wherever possible, but many offline/physical stores often require a phone number or email address to complete a transaction, so privacy goes out of the window even when using cash.

<comment><USER15> Good point. There is a rumor among my local IT fellows, that some banks who also run an insurance companies (or partner with some) share transaction information with insurance guys to help them identify whether discount is possible for a specific person or not. E.g. if someone frequently spends a lot of money in pubs, most likely that someone will have health issues sooner or later. So better to increase the insurance fee.

For sure such information trading is illegal, but as the government doesn't give a single care, most likely it is true.

<comment><USER16> >There is a rumor among my local IT fellows, that some banks who also run an insurance companies (or partner with some) share transaction information with insurance guys to help them identify whether discount is possible for a specific person or not. E.g. if someone frequently spends a lot of money in pubs, most likely that someone will have health issues sooner or later.

Or worse, what if they decide you had too much pub spending/fast food, so you can't get that new organ you need?

I keep my "entertainment" budget (pubs, eating out, etc) in cash for this reason.

</comment></comment></comment><comment><USER17> This is huge systemic risk (the possibility that an event at the company level could trigger severe instability or collapse an entire industry or economy).

When the systems in major Nordic bank (Nordea, Danske Bank) or payment system (Visa, MasterCard) goes down, people can't do anything until it's fixed. These things are rare but they happen. Usually it's just few hours, but if the condition persists even few days it becomes a major problem.

Mobile payment and cards are nice, but cash is good backup system.

<comment> o-o- > if the condition persists even few days it becomes a major problem

How much cash does a person keep handy? If the condition persists a few days, cash would also become a major problem.

<comment><USER18> Such as when the Irish banks went on strike for about 6 months in the 70s. Edit: It was a lockout not a strike.

They survived using olde worlde approaches with no loss of GDP growth or retail sales. The retailers and local pubs operated as banks and managed the movement of IOU credits and cheques. Publicans, as it turned out, were a pretty good gauge of credit-worthiness and extent. Cheques ended up counter signed dozens of times as they were passed on person to person many times. Retailers would offer cheque cashing to keep money circulating.

[http://uk.businessinsider.com/pubs-replaced-banks-in- ireland...](http://uk.businessinsider.com/pubs-replaced-banks-in-ireland- in-1970-and-the-economy-was-fine-2016-1)

Now try that with an app. :)

<comment><USER19> Fascinating and an excellent point, thanks.

</comment></comment></comment></comment><comment><USER20> > Swedish legislation makes it possible for retailers, restaurants and other > companies to refuse to accept cash, for instance by putting up a sign at the > entrance or by the till.

Yes. It started as a curiosity and now this signs are everywhere.

> By connecting a bank account in any bank with a mobile phone number, Swish > has become a popular way to share a restaurant bill

Yes. And to gather money for a friend's birthday or anything else.

> Why Sweden's cashless society is no longer a utopia

I see the potential risks of this situation. But the article does not bother to bring an analysis of them.

One thing is already happening. The oldest part of the population have a hard time adapting to this situation. It's easier to take a bus and pay in cash than to have to buy an e-ticket in your phone.

I would prefer to see such analysis than this e-krona nonsense.

<comment><USER21> I suppose the oldest part can get a card like SL has and occasionally load it with cash and then just beep it when entering the bus/train? It is no more difficult a concept than having a library card. They'll certainly get help with the process at the ticket counter.

Is it a real, factual problem that old people cannot somehow pay for their mass transit in the year 2018?

</comment></comment><comment><USER22> I was really shocked when i experienced the same issue in the Netherlands.

I went there for a conference and only had to go straight to Amsterdam central, to science park and to my hotel in almere central.

I had to exit Amsterdam central station by scanning in the QR code of my paper ticket. The alarm at that station was ringing constantly because of all the foreign tourists who had no idea what to do.

Outside I had to go to the foreign help desk which was nice enough to give me some kind of tourist paper ticket, which i do have to say, i have no idea how it worked. Hopefully it was a rfid chip in the ticket, otherwise i triggered every last scanner by just pushing it on top and walked out. And every last person was heavily annoyed by all the retarded tourists. It did not help, that apparently the Netherlands do not bother to put up English signs.

I luckily could pay in cash for the toilet in central station, but that was really it when it comes to cash. I luckily could use my VISA for a train station locker, but i could not buy a bottle of water, as the machine at main station only took some kind of wireless card. The same applied to every supermarket but one near my hotel.

I stood in 3 ordinary supermarkets and wanted to buy a simple bottle of water. Thankfully one of the cashiers in the supermarket at science park was nice enough to pay for a bottle of water for me in exchange for cash.

How every nice the Netherlands are, it is a modern Dystopia.

<comment><USER23> > The same applied to every supermarket but one near my hotel.

I've been able to pay everywhere I've been to in the Netherlands with a normal European debit card with chip + pin (Maestro I think)

<comment><USER22> I gave them my Visa and V-Pay card, and only one of the patrol stations took it.

Everyone else willing to take my non Netherland card were places who would also take cash, like mcdonalds.

There seemed to have been a certain kind of regional card which i did not have.

edit: dont take me wrong, i should have looked up the local payment procedure before going there, I was just extremely surprised as this happened to me directly across the border inside the EU.

<comment><USER24> V-Pay should be accepted by any shop in NL. I am not sure where the issue comes from, as there is no card, specific to the region.

In NL maestro/v-pay cards are accepted 100% of the time, because those cards are issued by all banks there.

<comment><USER22> I tried it, maybe it was the language barrier but I had shops who simply send me away. I had a longer conversation with the cashier in the SPAR shop on the science center campus about it who told me my v-pay card was the wrong one and cash was not an option. It worked out in the big shopping center in Almere where people also took cash.

</comment></comment></comment></comment></comment><comment><USER25> The article says circulating cash is 1% of GDP and falling. In the US, it is 8% and rising (with a high of 12% in 1946 and a low of 4% in the early 1980s)

[https://fred.stlouisfed.org/graph/?g=lZye](https://fred.stlouisfed.org/graph/?g=lZye)

Edit: See also this table

[https://www.bis.org/publ/qtrpdf/r_qt1803/images/tab6-A.jpg](https://www.bis.org/publ/qtrpdf/r_qt1803/images/tab6-A.jpg)

(from [https://www.bis.org/publ/qtrpdf/r_qt1803g.htm](https://www.bis.org/publ/qtrpdf/r_qt1803g.htm) )

</comment><comment><USER26> I can't find the article, but didn't another Nordic country, where they're going cashless already find a flaw? Their communication infrastructure had some sort of disruption, I don't think it was an attack, but a failure of something for like half a day. Because of that, merchant services were screwed. Few people could buy anything since few carried cash.

Don't get me wrong, I barely carry cash on me. I just have a bit in a safe. But I recognize the vulnerability. Natural disaster. Black out due to a node failure or two. An actual attack on the merchant services infrastructure or bank. Sure, cash can be stolen. But so can digital funds and you're not limited to how much you can fit in a bag and carry.

It's also funny how folks complain about privacy and not wanting private entities to have their nose in their personal lives and track what they do. Especially those Vikings whine about that regularly. Yet they trust how much data with merchant service companies?

<comment><USER27> Back in the old country we had a dozen currencies, gold and jewels hidden in a fake brick for that exact reason.

When you need to buy a train ticket to get away from the Germans or Russians you don't want to be asking "Sorry do you accept AmEx?".

<comment><USER26> I grew up that if the Russians or Germans are coming, you're going to use vodka as a currency.

</comment></comment></comment><comment><USER28> Hardly independent.... this is an advert for e-krona a crypto alternative to cash/electronic payments.

Strawman.... title is built on a false premise that someone argued Sweden's cashless society was a utopia.

Can't believe I clicked on this.

<comment> o-o- Advert? E-krona doesn't exist. It's not in development, and there isn't even an architecture in place.

The "advert" was written by the Deputy Governor of the Central Bank of Sweden.

</comment></comment><comment><USER29> headline is a bit overblown compared to the conclusion of the text.

> no longer a utopia

was it ever? who ever claimed it was a "utopia"?

main points:

\- If cash stops working, it would leave all individuals to rely on the private sector alone to get access to money and payment methods.

* One option is to do nothing, meaning we accept that the general public no longer has access to central bank money.

* A second alternative is to issue central bank money in a digital form, as a complement to cash and the money held in bank accounts.

seems like they've been thinking about this for a while

<comment><USER30> There's an alternative to relying on the private sector, which is for cash to be replaced with credit notes. The Irish bank strikes of the early 70s is a nice case study of this happening [1].

I've recently been thinking about a potential solution to the reliance on private institutions in a cashless society. I guess the problem with a "mobile chequebook" or something of the sort is that you are always to some extent dependent on a private service (e.g. phone signal provider).

[1][https://en.wikipedia.org/wiki/Irish_bank_strikes_(1966%E2%80...](https://en.wikipedia.org/wiki/Irish_bank_strikes_\(1966%E2%80%9376\))

</comment></comment><comment><USER31> I like physical cash. I don't always use it, and generally use my points earning credit card at places I frequent, but don't at places I'm new to or have no intention of returning to (unless I don't have enough cash on me). The number of times my card has been stolen has entered into the 10s, even in our new chip card era (I've had three chip cards compromised, but can only definitively attribute one of those to it having been stolen after typing it into a website. i.e. no chip involved). Apple Pay and its ilk are a step in the right direction (and convenient because they still work when the physical card is cancelled), but still traceable and beholden to additional parties.

If I'm somewhere where I think the transaction might be sketchy, I can pay cash and not think about it any further. Skimming, however, is still a thing and every time my card is stolen it causes me an inconvenience that would not exist if I'd used cash.

"Bitcoin/cryptocurrency will fix this!" some of you will say. Perhaps, but it's got a long way to go. All the USD I have in my pocket still says "this note is legal for all debts, public and private", I don't personally think a sign saying "we are cashless" at the cash register after I've ordered my food is acceptable (those establishments I've encountered didn't accept bitcoin, either).

I acknowledge what it says on usd currency is somewhat tangential to a Swedish cashless society, but I still think cash should be king, or at least always accepted.

<comment><USER32> Chips use a private key to sign transactions and can't be copied, at least without being taken apart. So they are secure if all merchants require digital signatures. But for credit cards, they don't do anything to prevent your number from being stolen.

</comment></comment><comment><USER33> Why does there need to be a separate government issued digital currency?

Presumably all of the private accounts that people are currently using are measured in Kr already, and the banks already operate at fractional reserve so the actual paper doesn't exist. As an American, I make about one cash purchase a year, but that doesn't mean that I'm not spending US Dollars.

It seems to me that calling digital money "e-krona" will change exactly nothing but nomenclature.

<comment><USER34> > The development raises some crucial issues regarding the state's role in the > payment market. For hundreds of years, the public has been offered central > bank notes and coins. If cash stops working, it would leave all individuals > to rely on the private sector alone to get access to money and payment > methods. This would be a historical change without precedence. Norway is > seeing a similar trend, and the two central banks are cooperating in this > area. In the Eurozone, cash is still used to a high degree. The value of the > outstanding amount of cash is equivalent to 10% of the Eurozone GDP, versus > the Swedish equivalent of only 1%.

A government system ideally guarantees access to every citizen/entity desiring to possess "cash". A system run by a private entity doesn't have to do so. If you don't agree/fall out of compliance with the terms of service of a private system, you can be banned. The same can be done on a government system, but at least you have the option of court intervention and voting people into/out of office.

<comment><USER35> Private entities can be regulated to the same effect on the matter of access.

<comment><USER36> As the article discusses:

> One option is to do nothing, meaning we accept that the general public no > longer has access to central bank money. Such a future would imply a changed > scope for the public sector. The payment market would have to be regulated > and supervised in new ways to meet fulfil the objective to have a safe, > efficient and inclusive payment market.

> A second alternative is to issue central bank money in a digital form, as a > complement to cash and the money held in bank accounts.

</comment></comment></comment></comment><comment><USER37> Related reading: "If plastic replaces cash, much that is good will be lost – Brett Scott | Aeon Essays" [https://aeon.co/essays/if-plastic-replaces-cash- much-that-is...](https://aeon.co/essays/if-plastic-replaces-cash-much-that-is- good-will-be-lost)

</comment><comment><USER38> One thing I haven't seen mentioned which is of particular concern given recent developments is that if society is cashless, what if the bank or "swish" or whatever private company is running cashless transactions decides to "deplatform" you because they don't like your political opinions (or the color of your tie, or anything else). Its one thing for a social media site to erase someone's online presence, or a hosting company to prevent you from having a web presence, or even Paypal preventing you from getting electronic payments through there service - because your life doesn't depend on it. If 'swish' decides it no longer wants your business, how do you survive? How do you buy food? How do you pay the rent? Aside from the Orwellian privacy/tracking implications (by both governments and corporations), the massive transfer of power to electronic transaction corporations is frightening.

<comment><USER39> This is exactly the "no longer utopia" part of the article (or the extreme end of it anyway). With private systems, this is a real possibility.

</comment></comment><comment><USER40> The article avoids mentioning the most important issue around central bank issued digital currencies:

Currently my electronic cash balance represents a deposit at a commercial bank. On the other hand, when I hold physical cash, it is a direct obligation between the central bank and I. As mentioned in the article, 90% of cash balances are electronic money held at Commercia banks.

With a central bank issued e-krona, there is no role for commercial bank deposits, the e-krona is a direct obligation between the central bank and individuals/companies. This means that commercial banks have very different balance sheets to use for lending. It fundamentally changes the financial system and creates very different payment and lending opportunities.

Initially the central bank may only issue <10% as e-krona to avoid this impact, but it makes little sense not to follow through to making e-krona the only form of cash.

</comment><comment><USER41> The propriety solutions and its near monopoly in both Sweden & Norway (and perhaps other countries) are also due to the slow expansion and adoption of Apple Pay and Google/Android Pay into those countries.

Apple Pay was only launched in Norway earlier this year and Google Pay only a few weeks ago. So the propriety solutions have had a lot of time to establish their monopoly.

Also, Apple/Google pay uses the Visa/Mastercard/Amex networks whilst 8 out of 10 of all card transactions in Norway is via BankAxept. BankAxept payments are near instant and has a very low transaction fee. A flat fee of 24 øre (0.03 USD) which most of the time a lot less than Visa/Mastercard that charge 1-2%.

You will find a lot of independent merchants in Norway, e.g. corner shops that won't accept Visa & Mastercard, but only accept BankAxept. This is also why Apple Pay only works in a few places, compared to the UK where I live where Apple Pay is accepted nearly everywhere.

[1] [https://www.norgedaily.com/google-pay-launched- norway/](https://www.norgedaily.com/google-pay-launched-norway/)

[2] [https://en.wikipedia.org/wiki/BankAxept](https://en.wikipedia.org/wiki/BankAxept)

[3] [https://no.mobiletransaction.org/bankaxept/](https://no.mobiletransaction.org/bankaxept/)

<comment><USER42> > Also, Apple/Google pay uses the Visa/Mastercard/Amex networks whilst 8 out > of 10 of all card transactions in Norway is via BankAxept. BankAxept > payments are near instant and has a very low transaction fee. A flat fee of > 24 øre (0.03 USD) which most of the time a lot less than Visa/Mastercard > that charge of 1-2%.

For comparison, in Finland, where debit cards are all VISA and Mastercard, the merchant rate for those cards is usually ~0.3% (with Nets capping it at 0.75€). Non-EU cards have higher fees.

(Finnish source e.g. [https://www.yrittajat.fi/uutiset/572780-maksupaatteet- hintav...](https://www.yrittajat.fi/uutiset/572780-maksupaatteet- hintavertailussa-izettle-nets-vai-verifone))

</comment></comment><comment><USER43> The article failed to give any real detail about what is being proposed. I suspect it would have to be something like Taler[1] where the buyer is anonymous but the seller is not. That allows the collection of sales taxes and allows the government some control over the currency.

[1] [https://taler.net/en/index.html](https://taler.net/en/index.html)

<comment><USER44> Note that the article is about Sweden, which has a VAT, not a sales tax. One great property of VATs is that they encourage reporting.

</comment></comment><comment><USER45> This is a major societal change. I for one believe there needs to be a tangible method of payment where a 3rd party is not requried for transactions.

I don't care if it's cash or some digital payment coin/card. The point is,people nees to be able to transact without a 3rd party and be able to buy physical tokens(as opposed to wire transfers and digital tokens).

People are too careless when changing fundamental aspects of their society. Payments can be made convenient,peer to peer and have a small amount of participation barriers.

</comment><comment><USER46> Last night, I stopped at an ATM on downtown Mountain View, to get some cash.

I have my debit card loaded in Apple Pay, for the sole purpose of making my ATM visit faster.

The ATM told me that my virtual card wasn't acceptable to use to pull out cash; it advised me to use a debit card from my virtual wallet.

Except, that's what I was using.

It was 8:30 PM, and I didn't expect any prompt support from the bank. So, I used my physical debit card.

I consider both real and virtual cards to be conveniences, but they're definitely not replacements.

</comment><comment><USER47> Cashless society is not an utopia, it's an antiutopia. Every penny you pay or receive cashless (unless it's some sort of privacy-centric crypto) is monitored.

<comment><USER48> The e-krona will most certainly need to be a decentralized ledger or I don't see the point at all. For centralized (I.e monitored) transactions the systems we already have are good enough.

</comment></comment><comment><USER49> My problem with cashless and just about everything electronic tech is: What happens when the network/power fails? What's the goto alternative? No one seems to point that out? It should not stop progress but it's important to make contingency plans in case of mass failure.

I wonder if salt as money will be fashionable again? :)

<comment><USER50> If we ever have some sort of apocalypse, I'm guessing that the popular barter commodities will reflect society's vices: cigarettes, alcohol, coffee, sugar and porn.

<comment><USER51> Since most porn is produced and consumed digitally (I assume - it's not something I pay attention to), in an apocalypse I doubt it would be a viable commodity. Any apocalypse worth its salt takes down the grid.

Prostitution would likely increase, though.

I'll add salt to your list as well.

</comment></comment></comment><comment><USER52> We need control over those who control our credit. As I read this article I've just arrived in London - my 4th trip here in as many months. And CapitalOne has started declining my charges again - even though I'm staying at the same hotel with the exact same charges as always. I have about $20,000 in credit with a zero balance, but that doesn't seem to matter either. I tried calling them before the trip - and was told that they don't need advance notice of trips. (I guess their fraud protection is so good - they just stop accepting charges.) And of course they only accept calls to resolve the issue - and on these international trips I usually don't have easy access to a phone. We are essentially prisoners of these credit card companies.

</comment><comment><USER53> It's weird to me that their version of cashless doesn't work for foreigners. Every vendor in South Africa takes Mastercard or Visa, or a mobile payment system backed by a credit card. It's not strongly linked to a local bank account. Not a cashless society, but the transition would be pretty smooth for me.

When I travel to Europe, UK, Australia I have the same experience (maybe not quite the same ease of mobile payment).

The only reason I'm not cashless here is cash tipping, 99% to homeless people or very poor sales people on the side of the road. For weeks now I've been getting frustrated with myself for not having any cash in my wallet and having to disappoint people, although at the same time grateful for the ease of not dealing with cash.

</comment><comment><USER54> Hmmm... quote,

> The basic concept for e-krona is as follows: it would be digital, and have a > 1-to-1 conversion with an ordinary krona held in an account at the Riksbank > or stored locally, for example on a card or in a mobile phone app.

> The technology to build a functioning e-krona is already available today. It > is not dependent on using distributed ledger technology and it is not to be > confused with cryptocurrencies.

I'd like to know what this available technology is, that can create a digital object that guarantees a 1:1 correspondence to a physical asset, cannot be duplicated or multiple-spent. Has Sweden discovered the un-copy-able bit?

<comment><USER55> Banks, Visa, PayPal, pretty much most in-game currencies, as long as your maintain control over the data storage and deny access to malicious actors there is no reason why a traditional DB system would not work.

</comment></comment><comment><USER56> As strong as I hate dealing with cash, it can't be dismissed in current society. In many places you don't want to use card as it's sketchy, in many places you don't want to have a log in your bank account (like going to a bar midday on a Tuesday).

Not to mention a classic meaning of cash, or just money: you get things for it. If you are getting robbed one thing is to give $40 because that's all you had in the wallet and completely other getting robbed for all money in your account. That's just one scenario.

I'm not sure I would want to live in a society without cash.

</comment><comment><USER57> This article is just fear-mongering and speculation. No facts are given to support the title, and the proposed solutions to the problem (which is never established) are vague to the point of meaninglessness.

Skip the read.

</comment><comment><USER58> More appropriate name would be "dystopia" because banning cash will have mostly adverse effects, intruducing nearly-totalitarian control over the citizens being the most important one.

<comment><USER59> If you are a Canadian citizen who ever used a credit/debit card at a cannabis dispensary (or if you even just invested or worked for a Canadian dispensary), you are now permanently barred from entering the United States. A cashless society is a totalitarian society.

<comment><USER60> Is this for real?

How would the the DHS or another US entity know about payment transactions made on a canadian bank account?

And, I realize that cannabis is not legal at the federal level in the US, but how would lawfully purchasing a cannabis product years ago disqualify you from entering the US?

<comment><USER61> I don't know about this specific case, but if you used a credit or debit card, it would be processed by Visa or Mastercard, which are both US companies, subject to US laws and regulations. That's how the US entities would know.

</comment></comment></comment></comment><comment><USER62> I'll repost an old comment of mine:

"The scariest part to me about cryptocurrency is not the greed, lies and manipulation. It's a centralized cryptocurrency by a major government. Imagine if instead of cash, you had to pay for everything with a digital currency controlled by the US Govt. It'd be all the immutability of cryptocurrency with the monetary policy of the Fed Reserve. I'd bet the IRS and NSA would love the additional data."

</comment><comment><USER63> Do dope dealers and brothels accept Apple Pay, or do people somehow get US dollar cash for those expenses?

<comment><USER64> I have heard about pushers using mobile payment services. Some even advertise their business on facebook.

<comment><USER65> I've never heard of a street level dealer in the US take anything but cash to my knowledge.

If you do, you're a good dealer and probably an outlier. Also, the further you go up the chain of command the less likely you'd be to run into someone accepting these types of payments as well.

I.e. the middleman might let you Zelle him the money, but he is probably paying with physical currency on your behalf to the actual dealer. The dealer might do the same, but the supplier is being paid with physical currency. The dealer supplier allows it, but his suppliers are accepting cash only. Etc.

Meanwhile you can use BTC to have those same drugs shipped to your door, through an onion based marketplace or whatever, or even the clearnet if you arent buying specifically controlled substances.

</comment></comment></comment><comment><USER66> I'm surprised central banks haven't become involved in digital currency before. I guess software isn't their core competence.

I guess if anyone can pull it off the swedes will. And I don't think they are offering a replacement to physical cash here - just an alternative

</comment><comment><USER67> Misleading title alert!!! It says nothing about it's being a utopia or having stopped being one. It is an interesting article about the eventuality of a truly cash-free society and its consequences. Only the title is stupid.

</comment><comment><USER68> The article makes Sweden into something it is not. First, Swedes are not as eager to adapt new technologies as it may seem from the text. Case in point, NFC is just arriving in the country and in one of the main grocery shops, that has its own bank as well, you can only use store cards this way. A small subset of cards are also still swipe-only. In all honesty, Poland seems like a better example of this as it is effectively the sandbox of Europe for consumer finance.

Second, this trend is visible in many countries in Europe. In my 7 years in the Netherlands before I moved to Sweden, it would be unusual for me to have any cash on me and in recent years the number of 'pin' (card) only points of sale there has been growing tremendously.

<comment><USER48> NFC terminals are growing at the same rate as NFC cards, but cards have a pretty long lifespan so my old debit card which is ~5 years old is still chip and pin, while my new credit card from the same bank is both chip+NFC.

I'm not going to go through the hassle (a few clicks) of replacing my card just to get NFC. The same goes for retailers, terminals get NFC on the next replacement.

<comment><USER68> Most of the terminals I see are NFC ready, but NFC payments are not enabled. In particular, ICA has Yomani terminals and does not accept cards not issued by them. In other countries NFC has been introduced years ago. In the Netherlands, most of the cards were replaced in 2013 and the full rollout of the tech was in 2014. The fact that a card is valid for longer does not mean that it cannot be replaced beforehand.

</comment></comment></comment><comment><USER69> How do tourists deal with Sweden? Can you get a temporary Swish account?

<comment><USER70> They better have VISA or Mastercard - those have even better coverage than Swish.

</comment></comment><comment><USER71> With physical money there is wear and tear, but every time a "digital" bill change hands 1-5% of it's monetary value is lost (transferred to someone else pocket).

<comment><USER32> That's only true with some digital transactions. In Europe most merchants that only accept local cards pay 0.3% or about 25 cents.

</comment></comment><comment><USER72> Isn't china's cashless move bearing similar problems?

</comment><comment><USER73> Everyone. Imagine you don't have a smartphone, or a bank account, or credit cards, or debit cards.

Can you survive? Can you pay for your housing, food, entertainment?

</comment><comment><USER74> It would only be acceptable if the cashless society supported both anonymity. It's the only way to avoid discrimination and enforce fairness.

</comment><comment><USER75> So, one can't spend a single penny there without being monitored, but let's instead talk how web cookies are cruel privacy invasion.

</comment><comment><USER76> Yay, state surveillance of every transaction....

</comment><comment><USER77> Cash is integral to financial privacy in the current world. Very sad trend to see.

</comment><comment><USER78> Similar thing in india is happening with a single monopoly player paytm.

</comment><comment><USER79> London is pretty much cashless, everybody uses Monzo fot everything.

</comment><comment><USER80> I recently took a road trip across North America, and was a little surprised by the number of cash only transactions I faced. Toll roads in particular were a big pain. It's kind of crazy that we don't support both methods in a reasonable way

</comment><comment><USER81> Who ever said it was a "utopia" with a cashless society?

</comment><comment><USER82> Why couldn't you send your friends crypto currency?

<comment><USER83> For the vast majority of people it would be a major inconvenience, requiring non-trivial time and effort to set up everything required to receive the equivalent of, say, $10 in crypto converted to the local currency in their bank account, which is the only place when it starts being usable money to them.

</comment></comment><comment><USER84> Not utopia, dystopia

</comment><comment><USER85> This is a common pattern - a bunch of disconnected from reality (literally, inside academical enclaves and mentally, living in a world of pure abstractions and ideas) pundits are advocating to destroy (or "reform") a vastly complex systems they do not fully comprehend, leave alone understood. Their abstract memes spread like viruses through naive minds of unthinking (or at least not thinking critically) people, and eventually society become literally sick with this or that nonsense.

This very pattern was behind marxism and all its tragic consequences. Exactly this pattern.

If you like a more recent example - look no farther than the crypto buble, based solely on memes and nothing but memes (well, very clever memes, indeed).

Cash plays a fundamental role in any society - it is means of anonymous, untraceable, quick payments. Any healthy economy needs this kind of transactions. It is literally what we mean by "liquidity" \- like a flow of red blood cells through the whole system. Do not mess with it.

The pundits would argue that cash payments could be abused. Well, kitchen knives (even forks!) could be abused too. Shall we advocate a kitchenless society?

Other countries have tried to mess with cash (India recently - thank god they kept _small_ notes in circulation) and the result was disastrous. Again, some disconnected from reality abstract ideas were used to justify the move.

What I am trying to say, is that this is the common cancer and the name of it is Liberal Arts "education", "humanities" and "academia". These people should not be allowed to govern because their minds are distorted with nonsense they have "studied" (memorized). Think of marxists or hegelians or platonists.

Sweden, unfortunately, has been ruled by platonists and hegelians, if not marxists, for last few decades. The results are... well, read the news.

</comment><comment><USER86> Cash is king.

</comment><comment><USER87> Racism! Stong word, but this is what the Swedish cashless society is: indirect racism. Those at the margins of society are excluded from participating in society because they don't have Swedish bank accounts or Swedish credit cards. Many clubs and pubs require that to enter. Indirectly, this means that non- Swedish (non-white) people don't get into the club. Not direct racism, but indirect (the outcome is the same, no white people allowed entry, or to participate in society).

<comment><USER83> What's stopping non-white immigrants (presumably residents of Sweden staying there for a nontrivial time) from getting a Swedish bank account? If there are significant barriers to _that_ then the "getting into a club issue" is a trifle compared to the broader participation in society. E.g. how are they getting paid for their work if almost no legal employers will pay salaries in cash?

<comment><USER48> I think it may be a misconception from someone from e.g the US where there is a threshold for getting a bank account.

<comment><USER83> Yeah, around here any old homeless alcoholic would have a bank account, because that's the only way how they'd get social security payments, and also any student (or working teenager) would have a bank account, because that's the only way how they'd get paid for a summer job or internship or study loan or whatever.

A bank account is a basic thing that's required (at least in come countries) for any participation in the economy and should be available to anyone; IIRC there's an EU directive about a requirement that everybody must be able to access basic banking services.

</comment></comment></comment></comment><comment><USER88> As a resident of Sweden, i can only say that this is the future for all western countries. Life is just better without cash. We don't pay the mental tax of always ensuring i have dollar bills on me to tip left, right, and center. Your phone is enough to get you through the day. The govt is still run by the people for the people here, so most people aren't worried about totalitarianism. Most beggars now have signs with their phone number to swish them cash - because nobody has cash to give them (the other form of begging is collecting plastic bottles and cans with deposits).

<comment><USER89> As long as you are fine with companies tracking every place you go (via GPS), everything you purchase, everything you view on line, and everybody you know. Then sure, the phone can replace cash.

Often I do not want any record that I have purchased something, I will stick with cash. Thanks.

<comment><USER90> "I don't care about privacy because I have nothing to hide" = "I don't care about free speech because I have nothing to say"</comment></comment></comment>


Ask HN: best (toy) robotics platform? - <AUTHOR>

Never mind that I don't really have the time for it, I am tempted by the Pleo. From YouTube videos I get the impression that it does not do very much yet, except purr and twist in a cute fashion, but maybe it could be programmed in interesting ways? For example I have read that it does not have image recognition that is capable of recognizing people (a ka it's owner). I wonder if there is a chance of programming it as an outsider, or is the hardware simply not capable enough?<p>Then again, if the cuteness factor is not the main attraction, perhaps there are other robotics platforms that are more interesting? Of course there is Lego Mindstorms - I just checked, and it doesn't seem to come with a camera per default. So maybe it is far behind the Pleo in computing power? Or what about Roombas, they can be programmed, too. Anything else? I suppose the Aibo was more capable than the Pleo? But the price tag is still too high (still >> 1000€ on ebay). <comment><USER2> One of my college professors used to build all sorts of things with a <http://www.fischertechnik.com/> set. I think he once mentioned that it was somewhat compatible with Lego blocks, but I see no evidence of that. Perhaps some pieces work...

</comment><comment><USER3> another option is lego mindstorm sets.

beyond that, there aren't any cheap, flexible, powerful home robotics kits.</comment>


Intel demonstrates how to send electrical power wirelessly - <AUTHOR> http://seattlepi.nwsource.com/business/376050_wirelesspower22.html

<comment><USER2> I don't want to sound like a neophyte here but I'm afraid of beams that carry that much power. I have no problem at all letting the milliwatt beam of my cell phone go through my head but lets just say I don't my bedside alarm clock powered by this just yet.

Coupled resonance seems safe to stuff that doesn't resonate in between but when I hear beam and _watts_ I still freak.

</comment><comment><USER3> Wow. 75% efficient at 1 meter is amazing.

</comment><comment><USER4> It's good to hear that Nikola Tesla found a job with a new company, after losing that Westinghouse contract.

</comment><comment><USER5> "Soljacic, who didn't work with Intel, said Thursday that he was pleased that Intel is getting behind the technology.

For me, it's like a confirmation that it's so exciting, it's something people would like to have," Soljacic said."

Yeah, I never would have guessed that people would want wireless power. Good thing Intel's there.

<comment><USER6> Apart from being cool as, what will wireless power do for us? As long as traditional methods remain more widespread and efficient at the moment I can't see what will make this technology take off. Perhaps recharging embedded medical devices? What else? There must be loads of interesting applications.

<comment><USER5> That's like asking "what would wireless phones or wireless internet do for us?" If you don't have the vision to think up 100 practical uses for wireless power and the sense of history to realize that those 100 would only be the tip of the iceberg, startups may not be for you.

<comment><USER6> Wow. Who pissed in your cornflakes? I agree with you. That's exactly what I'm saying, what do you think these applications would be? I probably could list a bunch but I'd rather hear ideas from people who've had more than a couple of seconds to think about it.

EDIT: I should point out that there was no sarcasm or innuendo in my previous post.

<comment><USER5> Sorry, I didn't really mean you specifically, was just generalizing. Wireless power seems like it might be the next world-changing invention.</comment></comment></comment></comment></comment>


Ask HN: Why haven't fitness gaming experiences taken off? - <AUTHOR> People want to stay fit or lose weight. People love gaming. So why not combine the two?
Peloton has done well, and it seems their platform would work well when combined with games. So why haven't they or any others attempted this or been successful in doing so?
Are there any companies working on a product that might work? <comment><USER2> Do more research. There are loads of fitness games around for the Wii, Xbox Kinect and PS4 Move that did well (in terms of fitness, not so much in terms of gaming).

<comment><AUTHOR> I see your point - but I see those as valuing the gaming side more than the fitness aspect. I am thinking in terms of a system that values the fitness side a bit more.

I can imagine a rocket league type game where your speed would be tied to cycling speed on a peloton-like device.</comment></comment>


Today is Linus Torvalds birthday - <AUTHOR> http://en.wikipedia.org/wiki/Linus_Torvalds

<comment><USER2> Wishing you happy birthday linus . Many many happy returns of the day have fun.</comment>


Have we become too reliant on GPS? - <AUTHOR> http://www.vox.com/2016/4/10/11379698/gps-navigation-brain-problems <comment><USER2> This article conflates digital map and GPS shamelessly, making the argument very confusing.

First, even if I rely on GPS for turn by turn navigation, I still use the map to see the route and specially to locate myself when in a new area. Sometimes I look for a place to eat nearby and them I make the route just by looking at the map: walking is often a matter of choosing nicer streets, which the Google Maps route does not do well.

On the other hand, driving around always make me distant from the place I'm at. With or without turn by turn navigation. Without it, I just look at the map and make a route beforehand, never seeing anything around me in between - too worried on navigating for that,even if I am not the driver.

People traveling long distances by error was not unheard of before GPS. It was just less of a news item. Quite on the contrary, I bet they are less frequent today.

Also, a good share of the population always had problems reading maps. I guess they are the ones that depend the most on GPS.

<comment><USER3> That was the problem with Apple Maps. The digital map was awful, but the GPS directions were actually good.

</comment></comment><comment><USER4> Are we too reliant on GPS? I don't think so. There's Galileo and GLONASS, after all. Your smartphone probably already supports GLONASS, and I imagine we'll see widespread Galileo support once the constellation is more complete.

Are we too reliant on turn by turn directions? Maybe. On the other hand, stupid failures like the ones mentioned in the article are pretty rare. That's pretty much by definition, otherwise they wouldn't have made the news in the first place.

Are we losing navigational skills? Maybe. But what the article discusses isn't a lack of navigational skills, it's a simple unwillingness to use them. I'm sure that Syrian truck driver didn't go off course because lacked the skills to find out where Gibraltar is, he merely neglected to even make the attempt. It's a failure of planning, not a failure of skills. If someone leaves their house unlocked because they didn't double-check that it was locked when they departed, we don't call that a loss of door-locking skills, we just call it a failure to pay attention.

Finally, the article tries to shoehorn in a mention of self-driving cars, I guess because it's the cool thing at the moment. "It's not okay for a driverless car to get bewildered for a bit because it's in a city center." Well sure it is! People do that all the time! It's not like a self-driving car needs GPS in order to avoid crashing.

</comment><comment><USER5> One of my best friends is a firefighter, about 30 years old, but started a few years ago in his mid-20s.

During his training, the captain would take him out on training rides and absolutely berate his lack of knowledge of local streets of both the city in which they worked and in the other local cities that they were most commonly called to. This went on for months at a time until he could recite entire city maps nearly by heart.

He complained a lot at first about why they didn't predominantly use GPS, thinking "get with the times, folks" but in his blossoming career, he says it's pretty nice taking the rig out and just, with second nature, knowing where to go. This also comforts me as a citizen of the city, knowing they don't rely on a technology that could fail in critical moments to get to where they need to serve.

</comment><comment><USER6> So I recently encountered this. I used to think I was ok at navigating, but whenever I got into an unfamiliar area, I had a hard time navigating using maps and street signs.

But I have lived in Puerto Rico for 2.5 years now. Cell coverage and speed is very hit or miss, and the mountains and valleys make GPS and connected maps very unreliable. After 2 years here, I went from getting lost or turned around frequently to being able to navigate most of the island without my phone. And I feel like my sense of direction has improved significantly.

</comment><comment><USER7> The truth is that navigation apps are not really designed to give you a larger sense of your route but rather just what you need to do to get to the next turn. Partially this is due to the relatively small size of smartphone screens but it is often actually actively difficult to zoom out or scroll ahead while in navigation mode. It's so focused on the details that you miss the big picture.

What if you made a different kind of navigation app, one that was designed to help you learn the streets as your travel? It could teach your about the main freeways and arterial roads. It could monitor your driving and give you points when you successfully reach your destination without turn-by-turn "hints" (though it would be ready to help you out if you got too off-course).

Granted, I'm not sure how big a market there would be for kind of app, but I'd love to try it. I think it'd be an interested experiment at the very least.

</comment><comment><USER8> I grew up in the rural Pacific Northwest, hunting and fishing, and I was taught land navigation via compass and topo map. I still enjoy using these tools to hike cross country, and even for following main trails. But it boggles my mind how many people I see out in the deep woods, with only a gps or phone as their only navigation aid. Electronics fail, my map and compass have never failed me.

<comment><USER9> _Electronics fail, my map and compass have never failed me._

Fail? Shit, for hiking scenarios they just plain don't work half the time due to terrain and tree cover. Dedicated GPS units seem to have improved a lot, but there's no way I'd rely on a phone for guidance. I, too, grew up on compass and topo map. My primary "good way to get lost" activity is trail running, and I always carry a paper map. It might just be the trail map from the trailhead, but at least it's _something_ that doesn't rely on batteries or an outside entity keeping their systems up.

So, yeah, perhaps "we" are too reliant if it has people wandering off into the woods with nothing but a cell phone. OTOH, those same folks probably would just wandered off with nothing but a hardy "I have a good sense of direction" if they didn't have a GPS.

</comment></comment><comment><USER10> This seems like a non-issue, or at least not a new issue. People can be bad at reading paper maps, bad at reading star charts, bad at using a sextant, mistake another star for the north star, etc...

Also, GPS, digital maps, route optimization, and turn-by-turn navigation are all separate things that this article kind of muddles together into the same "issue".

</comment><comment><USER11> The article also places a big emphasis on people driving to the incorrect locations, hundreds of miles away from their intended destination. To me, this is a user error rather than a system issue. Every GPS system has the user confirm their destination address to keep this from happening.

</comment><comment><USER12> Is "Is Google Making Us Stupid" making us stupid?

</comment><comment><USER13> I'm surprised they didn't make any mention of GPS spoofing, that's much scarier to me than jamming and is becoming easier and cheaper every year.</comment>


Something pg said over on reddit - <AUTHOR> http://programming.reddit.com/info/1gd49/comments/c1gi08 <comment><AUTHOR> I had a microcomputer when I was nine years old, in early 84. I was a bit late with email too (92 I think), but I was certainly using the web in 95 (my first real job was in the summer of 96, writing a web-based vertical search engine for British Telecom - I remember being disappointed I wasn't doing something more futuristic, so the web was old news to me by that point).

My only problem with this is all the things that I wasn't aware of at all until completely non-technical friends told me about them. I'm thinking of stuff like hotOrNot and MySpace particularly. Perhaps pg's comment applies at a higher level - broad technologies, rather than the uses to which people will put them?

In any case, I'd be really interested to know what people here are using today that they think everybody else will be using years from now...

<comment><USER2> I was a latecomer to most of those technologies. I didn't get my first computer until I was 10 (1991), and didn't start using e-mail regularly until 1996 or so. Was an early adopter for the web though; first encountered it in 1993, using Lynx, and also used Mosaic and Netscape 1.0 in 1995.

I think that the technologies you end up being an early-adopter of is mostly determined by luck, who your friends are. I wonder if PG has a FaceBook or MySpace account, or Twitters away, or plays Second Life.

"In any case, I'd be really interested to know what people here are using today that they think everybody else will be using years from now..."

Functional programming. It really does make that much of a difference. I'm a Haskeller by hobby, and my startup is Python-written-in-an-FP-style. I'm finding that almost all of my bugs are type errors, and I never get usually- much-more-common state or logic errors.</comment></comment>


How Newcomers Can Influence Established Groups - <AUTHOR> http://www.spring.org.uk/2009/07/how-newcomers-can-influence-established-groups.php

<comment><USER2> Wow, I thought I was just being shy, but I've been adhering to a similar strategy my whole life when joining a new group: stay back, let the group welcome you in instead of forcing yourself into the group. I also find that befriending single members of the group outside of the normal group environment works well in gaining some legitimacy in the group. After friending one person, you just apply the transitive property of friendship a couple time and hey! you've got a ton of new friends.

</comment><comment><USER3> The basic point seems to be "if you're new, shut up". Probably good advice in most cases.

Perhaps the headline could be changed to "How Groups Perceive Criticism From Newcomers" - I was expecting an article about how a group changes based on an influx of newcomers, which has been a topic of interest on HN lately.

</comment><comment><USER4> This reminds me of a great book, "Situated Learning: Legitimate Peripheral Participation", by Lave and Wegner (an anthropologist and a computer scientist). This book deals with how newcomers to a community of practice interact with core practitioners to learn the central knowledge/beliefs of that community. As newcomers move from the periphery to the center of practice, their criticisms to the body of central knowledge become more acceptable to the community as a whole. This of course causes the "center" of the community to shift over time as new members cycle in to a community and old members exit.

</comment><comment><USER5> This article solidifies something that's been rattling around in my head for a month or three.

It relates to a post on HN (which I can't find now) about job interviews. I think the article was written by an interviewer, who said he liked to hire someone who could offer a knowledgeable, well reasoned critique of his organization.

The implication is that, if you're looking for a job, you should aim at doing that kind of thing. I had a problem with that, but I could not articulate it very well. This article filled in the gaps in my thinking.

Wish I could find that old post ....

</comment><comment><USER6> I think it is perfectly reasonable to take criticism from an 18 year veteran more seriously than from a 2 week new jack.

In both cases you are assuming to gain a new perspective from the experience of another human.. Is it not reasonable to assume that someone that has spent a vast quantity of time in a particular environment would have a better perspective than a new jack?

And, do we need a study to tell us that groups are hostile toward newcomers that give them criticism?

<comment><USER7> But that was not the group reaction. The article indicated that the group...

 _thought newcomers provided less constructive criticism_

 _agreed less with newcomers' suggestions_

 _were more negative about their criticisms_

If the group just wasn't taking the criticism seriously, they would ignore it rather than disagree with it.

</comment></comment><comment><USER8> I don't see why you would want to change anything as a newcomer. There's no way you are going to understand the process well enough by then. First get to know the people, figure out how they think, how they work and how they communicate. Then figure out what's wrong and start telling them about it. You have nothing important to tell in the first few weeks. Ignoring your criticism is the rational thing to do.

At a lower level the way to get change done is to agree with people on anything you find sufficiently unimportant. On the thing you really want to change you'll explain that it's really quite similar to what they've been doing before, except you start taking into account A, which should be something they can identify with. To be able to do this, you need to know who you're talking to.

</comment><comment> onreact-com I'm just experiencing "hostility to newcomers" on HN. My comments have been repeatedly voted down for no apparent reason. I just can't imagine people loving nuclear weapons and such so why vote me down for speaking out in favor of pacifism.

<comment><USER9> Not true. After reading through your past comments on this site as I have, you will see that the only times you have been downvoted are when you bring political views into conversations where it is almost entirely off-topic.

Plenty of your comments in other threads have been upvoted, so laying the blame for your treatment on the rest of the community here is disingenuous.

<comment> onreact-com It's not off topic to speak out against militarism on a post that is cheerleading the military for being hilarious. I know people in the US love guns and are proud to "liberate" countries in the middle east but in Europe people think differently. I was surprised to see militarism being hailed in a tech and business oriented social news community. You don't want my political opinion stop promoting the army.</comment></comment></comment>


The Architecture Twitter Uses to Deal with 150M Active Users - <AUTHOR> http://highscalability.com/blog/2013/7/8/the-architecture-twitter-uses-to-deal-with-150m-active-users.html <comment><USER2> Since tweets are very much like financial ticks (fixed size, tiny), we can put the numbers in perspective. Let's compare Twitter vs say, OPRA (North American options), a single "exchange" feed.

Twitter: 300K QPS, firehose 22 MB/sec, 400 million tweets/day

OPRA: 12.73M MPS, firehose 3.36 GB/sec, 26.4 billion messages/day

[http://opradata.com/specs/2012_2013_Traffic_Projections.pdf](http://opradata.com/specs/2012_2013_Traffic_Projections.pdf)

edit: Also worth noting, the _diff_ between OPRA 1/1/13 & 7/1/13 is ~256 MB/sec, 2.0 billion messages/day. So in just 6 months the existing firehose _increased_ roughly 10x Twitter's entire output and roughly 5x'd the number of messages/day.

<comment><USER3> Tweets are fanned out to more than a single feed and, in the "most important" cases, millions of feeds -- 31 million feeds for Lady Gaga. Your comparing 300K reads, which might not even include the sub-queries, to 12.7M writes. A single tweet from a single user would trump the writes; it's unclear whether it could be done in the same one-second window.

Twitter already does 30B Timeline deliveries a day, compared to the 26.4B of OPRA. Again, there is no telling what can be implied by a "Timeline delivery;" does it include pulling user and other secondary and tertiary objects? An HTML renderer? The doesn't say much for the capabilities and focuses on what they do.

There's also little comparison to be made on what powers OPRA. If Twitter can simply add nodes to their architecture, are they doing it wrong?

<comment><USER2> Securities work a similar same way -- When you're looking at your portfolio you're only directly monitoring the individual fields for the securities in your portfolio, not the entire firehose. The OPRA feed is an equivalent to the raw Twitter firehose, only much fatter. Once you integrate it into the last- mile display to the users, you're doing all the same things. This is typically done with multicast topic-style subscriptions by ticker / type of data. It makes sense that if Lady Gaga writes a tweet you only want it to be "1 timeline delivery" (multicast) as opposed to "31 million timeline deliveries", which is making your infrastructure do a lot more work. Granted, you're kind of limited by what the browser can do in this regard, so you're kind of stuck with the socket model.

<comment><USER4> Securities feeds are, I suspect, more write-dominant and have a much lower fanout rate. They also don't have the outlier-retweeting-outlier or outlier- tweeting-@-outlier problems.

<comment><USER2> Yes, much more write-dominant. Apps which are built on top of the feeds can create issues, though. E.g., An obscure ticker pasted into a chat room with 500 people instantly starts monitoring in all their windows -- not just the static price (equiv to a RT), but the live feed. That would be as if A RT'd B and suddenly all of A's followers added B to their timeline. The degree to which that happens depends on how many features like that are integrated into the app.

<comment><USER5> I have no idea why you're getting so much pushback. Products like those offered by Bloomberg ingest and distribute massive amounts of data in real time, as well. The comparison is completely suitable.

While their products for investment managers are mostly run off of persistent databases, the trader terminals rely on a high-volume, nebulous fan out. For many traders, a five second latency is unacceptable.

Incredibly interesting talk and a good write up. Twitter continues to impress! I was surprised to see Redis playing such a critical role, too.

<comment><USER4> Sometimes the pushback is right, sometimes it's wrong. He's been very good at explaining the different and heavy requirements of financial data feeds.

</comment></comment></comment></comment></comment></comment></comment><comment><USER6> > _Twitter no longer wants to be a web app. Twitter wants to be a set of APIs > that power mobile clients worldwide, acting as one of the largest real-time > event busses on the planet._

Wait, then why are they actively destroying their third-party app ecosystem...?

<comment><USER7> The two are not the same. It sounds like they are becoming API driven to support multiple interfaces and to put clear boundaries between systems.

<comment><USER8> Sounds like html. Or qt. Not 140 characters.

</comment></comment></comment><comment><USER9> This article cites its source as a talk by Twitter VP Raffi Krikorian. 38 minutes of video, audio, and slides are at [http://www.infoq.com/presentations/Twitter-Timeline- Scalabil...](http://www.infoq.com/presentations/Twitter-Timeline-Scalability)

<comment><AUTHOR> Thank you for sharing it.... I was wondering about the video.

<comment><USER10> I also enjoyed this presentation: [http://www.infoq.com/presentations/Timelines- Twitter](http://www.infoq.com/presentations/Timelines-Twitter)

It goes into more depth about how they handle timelines.

</comment></comment></comment><comment><USER11> > Your home timeline sits in a Redis cluster and has a maximum of 800 entries.

Wow, that's pretty cool. Congrats to antirez - it must be a nice feeling knowing that your software powers such a big system!

<comment><USER12> Redis is probably the most useful tool powering the internet after nginx. It really is an amazing piece of engineering.

<comment><USER13> I have not used nginx, and have never heard of it spoken about in such glowing terms. Can you maybe compare/contrast it with apache?

<comment><USER14> The biggest difference is that nginx uses an evented I/O, and handles many connections per thread/process, Apache can only handle one at a time. This allows it to to use far less memory per connection, and lets it perform reasonably under very high loads. It also has very low latency, even for small loads, and is relatively easy to install and configure on most platforms.

nginx does an excellent job as a reverse proxy for applications, there are many configurations where nginx acts as a load balancer, and serves static content, and everything else is passed off to a real application. It's also useful if you're running on a tiny VPS with very little RAM.

However, Apache has a few features that nginx lacks, like embedding languages into it like mod_php does, and per directory configuration, in that directory.

<comment><USER15> FYI: [http://httpd.apache.org/docs/current/mod/event.html](http://httpd.apache.org/docs/current/mod/event.html)

</comment></comment></comment></comment></comment><comment><USER4> Figuratively, Twitter have switched from doing a design rooted in Databases 101 (OLTP) to a design more rooted in Databases 102 (OLAP).

That is, they moved processing from query time to write time. And that's a perfectly legitimate strategy; it's the basis of data warehousing.

OLTP is about write-time speed. It's great for stuff like credit card transactions, where you only really care about the tally at the end of the banking day. The dominant mode of operation is writing.

OLAP is about read-time speed. You do a bunch of upfront processing to turn your data into something that can be queried quickly and flexibly.

One thing that's problematic about the teaching of database technology is that the read/write balance isn't explicitly taught. Your head is filled with chapter and verse of relational algebra, which is essential for good OLTP design. But the problems of querying large datasets is usually left for a different course, if it's treated at all.

<comment><USER16> Maybe at a high level, but OLAP involves precomputing aggregations and bit indexes. It's a pretty different beast.

OLAP is very rarely under real-time constraints and, when it is, it tends to push the heavy lifting out to OLTP.

<comment><USER4> Oh, I'm handwaving, not talking about the underlying details of star schemata, clever column representations and whatnot.

But I think the analogy is still correct.

Every such system has two functional requirements:

1\. Store data.

2\. Query data.

And every system has the same non-functional requirement:

1\. Storage (write) should be as fast as possible.

2\. Queries (read) should be as fast as possible.

However, per an observation I made a while back, complexity in the problem domain is a conserved value.

Insofar as your data requires processing to be useful, that complexity cannot be made to go away. You can only decide _where_ the complexity cost is paid.

You can pay it at write time and amortise that across reads. You can pay it at read time and excuse writes. Or you can pay it in the middle with some sort of ETL pipeline or processing queue.

But you must always pay it. The experiences of data warehousing made that bitterly clear.

So really, the job of a software architect is to take the business requirements as a non-functional requirement (an -ility) and then pick the architecture that fits that NFR. That includes dropping other nice-to-have non-functionals.

Twitter's non-functional requirement is that they want end-to-end latency to be 5 seconds or less, under conditions of very low write:read ratio. This suggests paying the complexity cost up front and amortising it over reads. And that's what they've done.

</comment></comment></comment><comment><USER17> This near hour long video is a deep look into Twitter's backend. Specially into the Firehose feature, Flock, etc. They go into detail on how they use Redis and even show one of the actual data structures they store in Redis. A must see video for anyone into high scalability.

[http://www.infoq.com/presentations/Real-Time-Delivery- Twitte...](http://www.infoq.com/presentations/Real-Time-Delivery-Twitter)

</comment><comment><USER18> I am playing the armchair architect and my question will be probably wrong in infinite ways,but I might learn something, what is the reason why the service has to write a tweet on two million timelines, wouldn't it be cheaper if they let the client build the page on its own via restful apis?

<comment><USER19> That is actually a very interesting question and it turns out that whether it's better to fanout on write or on read depends on a few different things. There's a very widely read paper on the subject you might enjoy:

[http://research.yahoo.net/node/3203](http://research.yahoo.net/node/3203)

<comment><USER20> The link doesn't seem to work (error: "Unable to connect to database server"); do you have an alternate link?

<comment><USER21> Not a link to the full paper, but a summary is presented here: [http://highscalability.com/blog/2012/1/17/paper-feeding- fren...](http://highscalability.com/blog/2012/1/17/paper-feeding-frenzy- selectively-materializing-users-event-f.html)

</comment></comment></comment></comment><comment> brown9-2 Here is a similar talk that Jeremy Cloud gave at QCon NY a few weeks ago: [http://www.infoq.com/presentations/twitter- soa](http://www.infoq.com/presentations/twitter-soa)

 _Jeremy Cloud discusses SOA at Twitter, approaches taken for maintaining high levels of concurrency, and briefly touches on some functional design patterns used to manage code complexity._

<comment><USER22> I would absolutely trust someone named Jeremy Cloud on this subject.

</comment></comment><comment><USER16> The surprise for me is that the core component is Redis.

My first guess would have been custom C code. Yeah, you have to do everything yourself. Yeah, it would be hard to write. But you'd control every little bit of it.

Obviously, I must not fully understand the problem and what Redis buys.

Sam Puralla (if you are reading) -- do you know why didn't Twitter go with a full custom system at its heart?

Josh

<comment><USER23> I'm probably a better person to answer this than Sam - I'm a former lead on this project - so I'll take a swing:

We chose Redis because it gave us the specific, incremental improvements over our existing memcached-based system that we required, without requiring us to write (yet another) component. There was enough to do, and this choice has turned out to be good enough, I think.

As the project progressed though, we treated Redis much like we did own it. We altered the wire protocol, changed the eviction strategy, and reduced protocol parsing overhead, for example. Much of that work has long since made it upstream.

[edit] grammar

<comment><USER16> Sounds like good engineering choices. I think of Twitter as having unlimited resources but, of course, that can't be true.

Two follow-on questions:

1\. Did your changes make it back into open source or were they only relevant to Twitter? When you say upstream to you mean on Redis or earlier in the Twitter pipeline?

2\. How much is Redis on the critical path? Is it 90% of the processing work in the large fanout cases?

<comment><USER23> 1\. Yes, most everything we changed is in the open source Redis code base. That's what I'm referring to as upstream, above.

2\. Redis is in the critical path for a majority of API requests. I can't provide a specific percentage.

</comment></comment></comment></comment><comment><USER24> Well... It seems that hisghscalability doesn't scale... Error from squarespace on that page.

</comment><comment><USER25> No one else seems to have noticed that these details are out of date. Twitter has publicly stated that they currently have "well over 200M active users". The stats are also misleading in that -- I'm pretty sure -- 300k reads and 6k writes per second are only referencing tweets. Flock, Twitter's graph database, handles more than 20k writes and 100k reads per second on its own (peak numbers available from the two year old Readme on Github).

[https://blog.twitter.com/2013/celebrating- twitter7](https://blog.twitter.com/2013/celebrating-twitter7)

</comment><comment><USER26> > Twitter knows a lot about you from who you follow and what links you click > on.

No kidding. But we don't care as we live in the glass house of a celebrity culture.

PS: downvote the quoted text if you must. My point is not obvious.

<comment><USER27> You realize it's public data, right? When I tweet something, I don't expect it to be private. HN knows a lot about me too.

<comment><USER26> Yup, I mentioned glass houses.

</comment></comment></comment><comment><USER28> >> it can take up to 5 minutes for a tweet to flow from Lady Gaga's fingers to her 31 million followers

Why not break the load up among a farm of servers? 5 minutes to deliver a single message? It's too bad multicast can't be made to work for this use case.

At least analyze to see if there's a pattern of geographic concentration of her followers and optimize for where their datacenters are.

Use peer to peer, let the clients help distribute the messages.

</comment><comment><USER29> Their setup is very similar to what we use at Fashiolista. (though of course we only have millions and not hundreds of millions of users). We've open sourced our approach and you can see an early example here: [https://github.com/tschellenbach/Feedly/](https://github.com/tschellenbach/Feedly/)

</comment><comment><USER30> Does anybody know how that compares to Facebook? I believe they do not use write fanout but instead rely on the search federation model (the model claimed not to have worked for Twitter).

<comment><USER21> Facebook uses a fan-out-on-read approach

[http://www.quora.com/Facebook-Engineering/Did-Facebook- devel...](http://www.quora.com/Facebook-Engineering/Did-Facebook-develop-a- custom-in-memory-database-to-manage-its-News-Feeds)

</comment></comment><comment><USER31> Scala is awesome language to implement scalable things, like Twitter services

<comment><USER32> Why?

</comment></comment><comment><USER33> They have a lot of RAM. Dang.

<comment><USER34> Not as much as I would have thought.

2TB can be one server: [http://www.supermicro.co.uk/products/system/5U/5086/SYS-5086...](http://www.supermicro.co.uk/products/system/5U/5086/SYS-5086B-TRF.cfm)

An expensive server for sure... but it's just one server.

<comment><USER35> In case people have a hard time finding prices for this, my vendor gives ~57k GBP ($85k) as the lower end price for configurations with that SuperMicro cabinet, 64 cores (8x 8-core CPU's) and 2TB of RAM. Dropping to 1TB lets you pick from a lot of cheaper cabinets and so the price drops by quite a bit more than half for the basic configurations.

</comment></comment></comment><comment><USER36> I really question the current trend of creating big, complex, fragile architectures to "be able to scale". These numbers are a great example of why, the entire thing could run on a single server, in a very straight forward setup. When you are creating a cluster for scalability, and it has less CPU, RAM and IO than a single server, what are you gaining? They are only doing 6k writes a second for crying out loud.

<comment><USER37> I do consider it a pathology when tiny services, or tiny apps in a corporate structure, act like they have the problems of Google.

You are not Google.

You do not have Google's problems.

You do not have scaling issues.

For you, N is small and _will stay small_.

Stop giving me this delusional resume-padding garbage to implement. For you, here, it is delusion and lies.

<comment><USER4> The point here is that Twitter really is one of the cases where vertical scaling is not, on the balance of non-functional requirements to engineering overhead, the right decision. They really do need to pay the complexity piper.

<comment><USER37> Oh, yeah. I'm speaking to everyone else :-)</comment></comment></comment></comment>


-REMOTE- Developer Jobs - <AUTHOR> Hi everyone,
Would you like to find a remote full-time job?
With my co-founders, we have launched a platform for developers that makes it easy. We have a bit of traction so far; a couple of people were hired through our platform.
Learn more and create your account: http://bit.ly/Join-RemoteMore-utm345
Kind(est) regards,
Boris Borisov Co-founder @ RemoteMore <comment><USER2> You can also check out 6nomads ([https://6nomads.com](https://6nomads.com)). It's a platform for engineers who are looking for a full-time remote job in a tech company. We select the best talents around the world and match them with fast-growing tech startups.

</comment><comment><AUTHOR> We are looking especially for JavaScript developers now (React, Node, Angular, Vue... everything).

</comment><comment><USER3> bit.ly tracking URL goes to [https://remotemore.com/candidates](https://remotemore.com/candidates)

<comment><AUTHOR> yep, good point - it just has UTM tagging:

[https://remotemore.com/?utm_source=HackerNews&utm_medium=For...](https://remotemore.com/?utm_source=HackerNews&utm_medium=Forum&utm_campaign=NewThread)</comment></comment>