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Determining Site Valuation (Bankaholic = $15M?) | noodle: afaik, in the case of bankaholic, it wasn't about primarily about obtaining the readership or revenue model, it was more about obtaining the quality content.i could be wrong, though. |
Determining Site Valuation (Bankaholic = $15M?) | alaskamiller: He was able to generate highly-valued sales leads from his audience. |
Does anyone WANT to build client software anymore? | vlad: I've written a shareware app with a good GUI. I am not interested in working on it or any desktop app. Xobni is the only YC company I've heard of where the primary product or solution is a desktop app, so I think YCombinator also prefers web based apps.By the way, I've always wondered--is there a feature in your product that monitors how often you mention RescueTime on news.YC and elsewhere? If there's not, or if it's not automated, you should add it. That way at the end of the day, you could see how often you've namedropped your product (as a measure of success). I'm only half-kidding. :) |
Does anyone WANT to build client software anymore? | shimi: I'll try throw something in the mix, there is a matter of fashion. Back in the 90's C++ win32/MFC development was the highly regraded, I guess I should note that VB6.0 was very in demand as well, The technology and the market trends have changes so also the developers.I for one don't like to write web applications (mainly because the technology fragmentation), and I prefer to use client application whenever I can.Having say that I can't see myself writing Win32 API as a day job in the near future, for all the reasons mentioned above. |
Does anyone WANT to build client software anymore? | DanielBMarkham: Sure.It's just another marketing/sales numbers-based decision. If I had an app that targeted MS Office apps, for instance, I wouldn't have a bit of a problem writing it on the client.I'd take it a step further. If I had an app that took a minute to load the first time over the web, I'd seriously consider just targeting the client and getting more bang for the buck.The reason some folks stay on the web is that people don't want to wait to use anything. If you can show them a working app they can play with in under 5 seconds, your click-through and sales go up. You can't do that with client apps.Nothing special about web or client, it's all just a numbers decision (or at least, it should be) |
Does anyone WANT to build client software anymore? | pm: Writing clients is fun; writing cross-platform clients even moreso. Each platform has its own design philosophy, and I find it engaging learning each platform's intricacies, and coming to understand the psychology behind each platform's demographic.I believe the greatest measure of an application is the user's productivity, and I believe most of that productivity is inherent in the design of the user interface. The users of each platform have different expectations of their user interface, however, so I believe it's my duty when developing cross-platform applications to be mindful of these expectations.The work may seem unglamorous to most programmers, but if you can't get the human half of the interface right, any gains on the computer half of the interface are moot. That being said, I think most YC hackers do have an appreciation for this logic, it's just that client software is overkill for their requirements. |
Determining Site Valuation (Bankaholic = $15M?) | mg1313: 8,000/day doesn't seem high but I bet they were very targeted and had a good conversion rate (especially that Bankaholic was on Google's top searches for certain terms).Now, if they bring also more people to work at Bankaholic then the site could do even better. |
Does anyone WANT to build client software anymore? | thorax: I actually really like building client software. And web software. And services. And agents/bots. And scripting engines.Yes, those people exist, it's just not trendy to write lower-level OS-specific software these days. Maybe it never will be again. |
ASK HN: Best practices for storing Credit Card information | noodle: 1) i don't believe that the act of storing the information in plaintext is illegal, but it could contribute to negligence suits if you mess up.2) 2- or 3-TDES (http://en.wikipedia.org/wiki/Triple_DES) encryption; fully secure & restrict access to whatever database you use and whatever system holds the database; SSL connection (obviously).having said all of that, is there a reason why you're not using something like paypal, amazon FPS or some other payment service? they kind of take the work out of this stuff by providing a secure way of accepting payments, including recurring stuff with stored CC#s. |
Does anyone WANT to build client software anymore? | zach: My advice: hire a sharp game programmer, specifically one who has worked on tools and has 1-5 years in the game industry. The pay is not that great for game programmers in that range of experience, so they can handle a startup salary. And they are typically enthusiastic and experienced in the right areas you want.Many such programmers are burned out or just laid off, so they will consider working outside of games, but you have to bait them a little so they know you're not a corporate dullard. I would suggest a job listing with some game-programmer keywords or even sneaking onto CreativeHeads or Gamasutra.I say this not in an exploitative mode, but because that was my profile when I jumped from games into a job as a 2000-era dot-com client software programmer. They specifically mentioned that they were looking for console programming experience because there were several former game programmers there who understood this dynamic. And I was quite happy with the time I spent there. |
ASK HN: Best practices for storing Credit Card information | kogir: All the major card companies banded together and formed a standards group:https://www.pcisecuritystandards.org/security_standards/pci_...Once you reach a certain volume of transactions you are required to comply. Doing so now is probably not feasible if you're small, but you can still take the spirit of the standard and do your best. |
ASK HN: Best practices for storing Credit Card information | olefoo: If you are processing credit card payments you are supposed to adhere to the PCI-DSS standards which do include encrypting Cardholder Data goto https://www.pcisecuritystandards.org/Get the self-assessment questionnaire and work through it.Encrypting columns, rows or tables in your database is trivial, pgcrypto will do this for you if have postgres. Or you can hack something together w/ http://php.net/openssl pretty easily. Whatever you do, don't try to write your own encryption routines, people will laugh at you and Moldovan teenagers will buy BMWs with your customers money.Set up views so that non-finance personnel see the last four digits only, and those with a need to know can see the full PAN and have their accesses logged to an audit table that cannot be altered without superuser privileges.Right now you can slide by, but in a few years your payment gateways and merchant banks are going to be insisting that even small processors have outside audits.And according to the standard you should never store the cvv2 code, you should request it each time.HTH |
ASK HN: Best practices for storing Credit Card information | oldgregg: Credit card storage is scary. I was working with a company that had 20k credit cards stolen. Visa never called, nobody was notified, nobody ever found out. Only a small handful of customers who had just placed orders even suspected who it was. We actually tried to notify the merchant and credit card companies and they were like "huh?"They don't store credit cards anymore. |
ASK HN: Best practices for storing Credit Card information | vaksel: Our cc processor has a vault for storing cc info, so this stuff is never on our servers, so we don't need to comply with anything. Check with your cc processor they might offer a service like that too. |
Does anyone WANT to build client software anymore? | dgabriel: Just out of curiosity, what do you see as "the YC hacker mold"? |
Does anyone WANT to build client software anymore? | Shorel: I was looking for a job a couple of years ago, doing precisely that, in wxWidgets. And everybody seemed to hate C++ and love Java and related 'new' languages.Right now, I'm working full time doing PHP and I want to keep the job stability even with that slow language, so sorry, too late. |
ASK HN: Best practices for storing Credit Card information | jcapote: Simple. Don't. |
ASK HN: Best practices for storing Credit Card information | there: you are definitely not supposed to be storing cvv numbers, in plaintext or otherwise. according to pci, you're not supposed to be storing or processing credit card numbers on the same machine (or even network, i believe) as your public web server.if you are not sure how to handle this stuff, please, for the sake of your customers, use a company that does know how to do it. companies like braintree (http://www.braintreepaymentsolutions.com/) have a secure vault service that lets you store credit card information on their servers which you then access on a per-charge basis using a token. |
ASK HN: Best practices for storing Credit Card information | umangjaipuria: Like everyone else is saying, don't. It's a lot of responsibility and that's not your main business anyway.
How about using something like Amazon FPS instead? |
ASK HN: Best practices for storing Credit Card information | jonknee: Don't. Use a gateway that can do this for you. Authorize.net does this pretty easily. The API is called Customer Information Manager and you can store not only CC, but billing info. Makes it easy to do lots of advanced stuff (it's a good option for recurring billing when you want lots of control).http://www.authorize.net/solutions/merchantsolutions/merchan... |
ASK HN: Best practices for storing Credit Card information | agotterer: I'm a developer for a large e-commerce site. We require users to input their credit card for each purchase (no save functionality). We store the credit card for the duration of the transaction. Which is usually a few seconds. The time it takes to do run an AUTH ONLY. During these few seconds cards are stored with 256bit encryption on a server not accessible by a public IP. We use the mcrypt library in PHP.I understand you want to save the cards for future purchases, but you should definitely give customers the option to input their card every time if they so desire. If you dont need the card in the future, theres no reason to save it. Most processing gateways will return a transaction id which you can use to take processing actions in the future. You can run voids, refunds or settle payment. For our site we settle payment once we ship the goods and its all done with transaction IDs. The only thing we hang on to is the last 4 digits of the card number as a reference.If you are going to store the card numbers use a good, well known encryption algorithm. Hashing isnt encryption, plus a one way hash will not work since you wont be able to recover the number to process.Its important you become PCI compliant, especially if you are selling a hosted solutions to other businesses. |
Does anyone WANT to build client software anymore? | nickb: Try doing few usability studies with client-side software (I'm really talking Windows apps) and you'll see how much pushback you'll get. Consumers just hate installing apps. They absolutely loathe it. Everyone seems to be afraid of viruses and software. Now, this can be overcome to a degree if you're a huge company and have a well-known brand name that people trust and you can also overcome it by targeting a specific segment of the market that are computer knowledgeable and are willing to trust you. I'm not sure but I think that Firefox addons have less push-back than regular apps (just a guess, have no data).So in short, make sure you do several usability studies with people who fit your market segment. |
How to build a twitter/irc/real-time app | collint: I would also look at RabbitMQ as the messaging service and the STOMP protocol to talk to everybody.As far as getting messages down to the browser.Use http://orbited.orgIt gives you a simulated TCP socket called WebSocket(soon to be standard in HTML5)http://js.io has some work on many common network protocols including XMPP and STOMP.If this is a very small deploy, you might skip RabbitMQ and use the sister prject of Orbited, Morbid. |
ASK HN: Best practices for storing Credit Card information | multifarious: As everyone else has said, this is not a good situation. You don't want the overhead and risk of providing software security let along physical security for the storage of personal information unless your business model depends on shaving the fractions of a percent that it may save you in processing.In all seriousness, get set up with a major processor and get on with your business. (PayFlowPro would work well for the recurring payments you seem to need as a feature.) |
How to build a twitter/irc/real-time app | aaronblohowiak: don't forget that the radius of one user is not the radius of another user. so, you and knuth are both near me, but knuth isn't near you. so when i respond to you in the "channel", should he see the updates? now, if you want to have me join and leave channels based on my proximity to a fixed location, that's a slightly different problem.you could do this all with xmpp.the wireless client reports location to your dispatch server, dispatch server responds with list of MUCs. the client does whatever filtering the user has setup or whatever and initiates the joins to the MUCs (basicly, the channels to use your terminology.)which xmpp server and client libraries, well that's up to you. ejabberd has a lot of inertia. |
How to build a twitter/irc/real-time app | sjs382: You just pretty much described brightkite. |
How to build a twitter/irc/real-time app | silencio: Whatever you do, don't forget about privacy features. One of my friends used to work on an app called Twinkle for iPhone (http://tapulous.com/twinkle/)...it's a twitter client with their own custom location feature so you can get all the nearby tweets (using their backend, because Twitter doesn't support it yet). The only reason why I refuse to use it with the location feature enabled is because I am thoroughly creeped out by some of the people close to me (http://www.flickr.com/photos/chix0r/2788921744/, you get the idea). Only with the recently released 1.2 is there a blocking feature, but that sucks when it's a different person bothering you every time. In fact, Twinkle probably wouldn't be the only app I have a problem with...anything that publicly announces my location gets on my nerves. I don't mind if friends know, but announcing it to the public is something else.Another consideration is that a user might want to continue in a conversation even though they're not in a location. I could actually maybe even see this as a benefit, if I wanted to join in on a conversation between people at, say, a conference without actually being there. |
How to build a twitter/irc/real-time app | guruz: Funny, Geocasting in XMPP was (roughly) the subject in my diploma thesis :) |
How to build a twitter/irc/real-time app | Tichy: I recommend programming a MMORPG as an exercise first. Sorry, couldn't resist ;-)Actually the idea sounds OK, if you stick to it, you could make it. |
How to build a twitter/irc/real-time app | lhorie: You could just grab the chat demo from jetty |
Good python code for code reading | jnoller: I would definitely recommend sync'ing the python subversion tree and picking a few modules and reading through them. Doing so taught me some of the less obvious things within the language, and also taught me a lot about the various dunder (__foo__) methods for objects.Additionally, I'd recommend reading through the PEP documents (http://python.org/dev/peps/) - there's a lot of great examples and rationales contained in those.Finally, Doug hellmann has done an excellent job with his Python Module of the Week series (http://www.doughellmann.com/PyMOTW/) and a new project "The hazel tree" (http://www.thehazeltree.org/) is doing a great job at compiling the various examples, docs/etc together in one place. |
Good python code for code reading | pogos: BitTorrent
http://download.bittorrent.com/dl/ |
How to build a twitter/irc/real-time app | Prrometheus: I've long thought something like this would be awesome to help people meet people in coffee shops/neighborhoods/apartment buildings etc. Don't just think people want local area communication on mobile phones, though!I call this class of apps "local social applications". |
Good python code for code reading | llimllib: pybloxsom is a nice project to hack on; you can read and understand the whole of the code in a day, and it illustrates the "request handler with filters" design pattern very nicely. http://pyblosxom.sourceforge.net/ |
Good python code for code reading | alecco: For performance and algorithms the implementations at
http://shootout.alioth.debian.org/u32q/python.php
and pay attention to the different benchmarks.Also all RPython code coming from pypy, sometimes shown in
http://morepypy.blogspot.com/They are reimplementing all the C modules and doing a great job. The new implementations are of course closer to current best practices in python.Enjoy. |
Good python code for code reading | stuartcw: I enjoyed reading the code from "Hacking RSS and Atom" by
Leslie M. Orchard (ISBN: 978-0-7645-9758-9). There's a lot more to it than just RSS related code and if you read the book you get the explanation too. |
Good python code for code reading | icey: It's an essay that contains code, but this is one of my all time favorites:Peter Norvig writes a spelling corrector in 21 lines of Python:
http://norvig.com/spell-correct.html |
Good python code for code reading | intellectronica: The Zope3 codebase. |
Good python code for code reading | olefoo: Mailman http://list.org/Things you should be looking at are queues and error handling in an asynchronous message passing architecture.Also you'll learn that not every web application needs an SQL database for persistence. |
Good python code for code reading | kilowatt: I learned quite a bit from web.py (http://github.com/webpy/webpy/tree/master). It's small enough to be fun to poke through, but has more than enough "advanced" Python tricks to be worth your while. |
What's a good startup PBX system? | RobGR: Firstly, think about if you really need to do this. Will a single line to a telephone that has an ansering machine suffice ? How much of a "professional" image to have to give to telephone callers at this point in time ? Fancy phone systems are one part of the "playing office" trap, where by people get fascinated by the stuff that makes you look like a "real business" and proves to yourself that you are "serious this time" and start spending time and money on furniture, unnecessarily fancy space, etc.Also, for most businesses, time on the phone is unproductive time. I think that many offices would benefit more from spending money on a cell phone jammer than they would on fancier phones.That said, if you have broadband internet then you can set up a PBX box for nearly free. Here is how I do it: I use http://trixbox.org/ or http://freepbx.org/ to get an already-configured asterisk setup. The hardware requirements are so low as to be free. I provision with vitelity.net or a similar company; vitelity allows you to pre-pay, so you can keep your costs very low when you are in the initial stages. For phones I use a combination of desktop software phones (only good for people who make few calls) and the cheapest, lowest-featured Grandstream brand IP phones.The FreePBX / Trixbox stuff has a web interface, and the IRC channels are very helpful (if sometimes snarky). You install the software, go to the IP address in a browser, and configure everything from there.The setup should take one afternoon. If it takes longer you are doing something wrong, or maybe you should just pay someone from craigslist $100 to come by and set everything up, and then occasionally call them to add new lines and stuff, which they should be able to do remotely.In spite of my anti-phone observations above, the FreePBX/Vitelity setup will have the following features a startup might find useful:* All calls can be recorded, and accessed via a web interface -- just check that option. (Note this has legal implecations -- I think you should be fine if you tell all your users that the calls are recorded, and tell them to always tell any person they are talking to that they are being recorded if that person asks.)* Voicemail can be delivered as a wav or mp3 attachment to your email, and there is also a web interface for browsing and listening to your voicemail.* You can get a text message when someone leaves a voicemail.* You can forward an internal extension to another phone, allowing someone to work from home but still get calls.* You can send faxes and receive them via email as a pdf or tiff file. The VoIP providers generally do not guarantee enough quality to do faxes, but it works well enough.* You can go into Vitelity's web interface, add a 1-888 number to your account, and have that number go to a special voicemail account. This allows you to try out a custom advertising method quickly and see if it works. You can just cancel the account after a month, and the whole experiment will have cost you a couple of dollars.I have set up a number of systems like this and I could do it for you if you are in the Austin, TX area. However, there is no reason why any reasonably technical person should not be able to set it up in a couple of afternoons, and I recommend you do it yourself.Or just scrap telephones. They are an inefficient way to communicate for most of what they are used for, and a waste of time, and a distraction. Make some money instead. |
Good python code for code reading | nirs: twisted is very clean and readable. |
Good python code for code reading | pistoriusp: I've always found Django to be a very clean code base. |
Good python code for code reading | mamama: The Cookbook (Amazon it, I'm too sleepy to link) contains examples of idiomatic code that you should use. |
Good python code for code reading | bayareaguy: Python ships with plenty of good python code. Just take your time and read through the Lib directory of your standard python distribution.http://svn.python.org/view/python/trunk/Lib |
Best Financial Advice Posts? | jakewolf: billcara.com |
Where do you turn for graphics/design work? | brm: Here is a good place, I'd need specifics but I'm a UI guy and looking for people to work with, hit up the email in my profile... |
Best Financial Advice Posts? | raju: There's "How to Get Rich" by Felix Dennis - http://news.ycombinator.com/item?id=283983There was some discussion on investment books too -
http://news.ycombinator.com/item?id=248469 |
Where do you turn for graphics/design work? | aaronblohowiak: this looks cool: http://collabfinder.com/usually, i find people through mutual professional experience. |
Best Financial Advice Posts? | brentr: Benjamin Graham and David Dodd's Security Analysis is not exactly on getting rich in the sense of the two works presented in the above question, but it is certainly a book on returning to the basics in the markets, which is exactly what needs to happen now. |
Where do you turn for graphics/design work? | dmpayton: I met my designer in 7th grade P.E. class. We were both into Pokemon at the time, and hit it off.Almost 10 years later, he's my go-to guy for anything and everything design related.http://www.artificestudios.com/ |
Where do you turn for graphics/design work? | ashishk: What's your budget? Would help to know.I know a two people in the $50-80 per hr range that are pretty solid. I know another one that's more expensive.Shoot me an email. |
Where do you turn for graphics/design work? | Flemlord: I've sucessfully used 99designs.com a few times and it's worked out great each time. With each new design need, I go back to the designers that won our prior contests. |
Where do you turn for graphics/design work? | vaksel: digital point forums has some decent people. I used them at first, but now I use 99designs since you get a lot more choices |
Where do you turn for graphics/design work? | lylia: My portfolio and some past work:http://www.rosefu.net
http://www.retributionclan.com
http://www.gameurb.com
http://www.rotary.org |
Where do you turn for graphics/design work? | mjnaus: Photoshop CS3 |
What type of companies will thrive in this environment? | alaskamiller: A bean cannery. |
What type of companies will thrive in this environment? | noodle: well, just as an example, ebay is struggling. they deserve to be toppled, and someone doing things right can topple them.especially in this market, where people are probably looking to hock their stuff. |
Where do you turn for graphics/design work? | kennyroo: I used elance.com to find a map designer for Planaroo.com. Prices were all over the map (excuse the pun), but I chose one of the more experienced and more expensive designers and was very happy with the results. I have no connection to elance. |
Where do you turn for graphics/design work? | sachinag: http://www.crowdspring.com - better than 99designs because they give you legal agreements that are enforceable. Oh, and there's no $40 posting fee. Crowdspring (I refuse to do their moronic capitalization) takes their money on the back-end, so unless you get 25+ submissions, you can walk and pay nothing. |
Where do you turn for graphics/design work? | josefresco: I'm a web designer, startup founder and Hacker News ...uh addict.Drop me an email and I can probably help you out. |
What type of companies will thrive in this environment? | ashishk: Google saw increases in revenue despite the shrinking economy (although this was before the recent events of the past few weeks). The explanation was that more consumers were going online to shop in order to save some money.I think businesses that by function, cut costs and increase ROI will do well. Just trying to figure out what the best way to do that is. |
Update from Midphase hosting status thread | mechanical_fish: Excellent news! Hope you are happier in your new home. |
Update from Midphase hosting status thread | vaksel: Congrats, your host is one of the most important decisions you'll make. And slicehost is one of the better options, frankly I never heard of midphase |
Good C (not C++) code for reading/learning? | silentbicycle: The source for Lua is pretty good (if a little dense at times), and you can read it in-browser: http://www.lua.org/source/5.1/There's a suggested roadmap for reading it, too: http://www.reddit.com/comments/63hth/ask_reddit_which_oss_co...It is written in ruthlessly standard ANSI C (for maximum portability).It will probably also complement your C -- it's intended to be a handy drop-in scripting language to embed in C programs, though it's also a pretty cool language on its own merits. They had an unwavering focus on keeping it clean and very small for embedding, and they make some really interesting choices along the way. It's sort of like a minimalistic Python; it gets a lot of power out of using "tables" (rather like Python dictionaries or Perl hashes) as a primary data type. |
Update from Midphase hosting status thread | tdavis: Let this be a lesson to everyone: the time you invest in finding a web host is critical. I went through 3 VPS and 2 Dedicated hosts before finally finding and going with Softlayer and boy oh boy was it worth the time and effort, not to mention the anger I caused other companies by calling them incompetent and issuing chargebacks ;) |
Good C (not C++) code for reading/learning? | SwellJoe: SQLite is always recommended in threads like this (of which, I will point out, there have been several here and at reddit...you might like to search for them). I haven't looked at it since very early releases, but I'm guessing quality has gotten better over time, since it is more stable than ever and faster than ever, and still astoundingly lightweight. |
Who do you use for stock market data? | nickb: I used IB for few years. Recommend them highly. Not sure how much they charge these days. They're very flexible, have a great API and their transactional costs are cheap. You can get more info here: http://www.interactivebrokers.com/ |
Who do you use for stock market data? | nose: http://download.finance.yahoo.com/d/quotes.csv?s=CSCO&f=... |
Who do you use for stock market data? | jack_alexander: I use Cottonelle...After all, the market is in the toilet. (Forgive me, I see a need for humor here.) |
On scalability and memory footprint | ezmobius: Yes there is a big advantage to keeping your memory consumption low with ruby apps. Ruby's garbage collector is not the best and has to walk all the objects in the process when it GC's. The more memory your process uses the longer and more often GC will happen. This will degrade performance the more memory you use. In fact I've seen really leaky apps spend most of their wall clock time in the garbage collector.Sure, throwing more ec2 instances at the problem is one solution, but if you care about your apps performance you will try to optimize for smaller memory footprint. |
On scalability and memory footprint | ashleyw: 1) Build your app how you would normally build it (obviously dont expect to put massive objects into memory for every request — just dont worry about the small things)2) Go back and refactor the things that really stick out as bulky3) Deploy4) Continue your release cycles and refactor stuff as you come across them.As the saying goes — hardware is cheap, your time isn't. |
Good C (not C++) code for reading/learning? | rmk: How about the Linux Kernel?
- Well-documented.
- Always good to know.
- Good, well-organised code.
- Real-life C code. |
Who do you use for stock market data? | mstefff: you'll need to spend much more per month for raw streaming market data |
Who do you use for stock market data? | furiouslol: try quotemedia, esignal etc. |
Good C (not C++) code for reading/learning? | RobGR: This is probably more than you are looking for, but the fftw code ( www.fftw.org ) is a pretty amazingly designed piece of C code that does some very advanced stuff. However, if you trying to get off to a good start, you might want simplistic examples.One thing I think helps you become a better programmer, is to read your own code carefully a long time after you have written it. |
On scalability and memory footprint | furiouslol: Here is my experience. I used Rails for one project of mine that requires processing of millions of data rows. Because the Rails ORM create an object for each data row, we end up using a lot of memory. We had to get a 2GB memory server to hold up the project. Even after we avoided the ORM (which removes the pleasure of coding in Rails), the memory usage was still high.Sure, we could process the data rows outside of Rails in C but because the processing of data rows is an integral part of the project, that would mean coding 80% in C and 20% in rails. Not exactly an enjoyable experience.So we rewrote it in PHP and avoid objects and use just functions and hashes/arrays. And it worked very well for us. The site render time drops from 0.8s to 0.03s. Memory usage rarely exceeds 100MB. |
On scalability and memory footprint | wheels: "We should forget about small efficiencies, say about 97% of the time: premature optimization is the root of all evil." -Donald KnuthThat said, watch your 'n's. If you scale linearly, you can keep throwing servers at the problem. If you end up with some critical piece of your code that's, say, quadratic in run-time or memory consumption, you can't. And when you get there: profile, don't guess. Monte-Carlo code optimization is the beginning of the end for an otherwise clean code-base. |
Who do you use for stock market data? | known: http://www.elitetrader.com/ |
On scalability and memory footprint | iamelgringo: Your bottleneck in a web app is almost always the database. In some cases, it's not. So, it depends.If, like furiouslol, you're trying to access a 2-3 million row table and Active Record is topping out at 2GB of RAM and taking close to 1 second on a production machine just to render a page, then yes, you might need to worry about memory usage.But, if you're prototyping a site, and just getting it off the ground, I would worry about memory usage later.If you're really freaked out about performance, you can always try PHP or Django. They tend to be a bit more sparing on system resources. |
ASK HN: Master degree in CS - USA or Sweden? | cinkler: It depends where are you from. |
ASK HN: Master degree in CS - USA or Sweden? | tuukkah: Your question is not specific: Which school are you about to graduate from? Which school do you plan to attend in Sweden or USA? What have you done this far and what do you plan to do next? What do you strive for in your life?At least, you should read http://paulgraham.com/cities.html |
Who do you use for stock market data? | TweedHeads: Not techcrunch for sure! |
Who do you use for stock market data? | lowkey: For real-time streaming API a low cost option is IQFeed.net which charges about $67/month for Nasdaq, AMEX, and NYSE + $50 setup. The data feed source is ComStock and the only API available is through Windows COM (yeah, I know)To offer real-time to the public you will need to set up agreements with each of the exchanges individually. Expect to pay about $1/user/month plus some fixed monthly fees.If real-time isn't essential, you could also use the fantastic python library ystockquote to get delayed data from yahoo. |
Who do you use for stock market data? | alecco: With so many trading companies going bust I bet the price will go down soon. |
Who do you use for stock market data? | Shamiq: TD Ameritrade (http://www.tdameritrade.com/tradingtools/partnertools/api_de...) has an API, though I can't say I've used it myself.Also, do you mind giving us a general idea of what you want to do? Hinting at a project without sketching out an outline is cruel. |
On scalability and memory footprint | tdavis: "Memory usage" is pretty vague. If you're just talking about writing poor code that naturally requires more memory to store objects and such, it's not a big issue if you can scale linearly. What you really need to watch out for is memory leaking. This can cause processes to slow down dramatically and there's nothing you can do to scale it when that happens; your app server will take requests and probably even have RAM to spare, but the actual processing of the request will take forever and your site will be sloooow. This is especially relevant for long-running processes. I have accidently written memory leaks into programs before that, despite having more than enough RAM to grow, eventually slowed down to an absolute crawl. I'm talking 1 loop per second to begin with and by morning it's doing 1 loop every 4 hours.Premature optimization? Avoid it. Writing good code? Don't avoid it because bad code is easier and memory is cheap. There are some times when it makes no logical sense to allow something to use tons of memory, despite how much you have available. For instance, if you request the same page from your site over and over again and the memory usage continues to increase, that's probably a bad thing. What is that process storing in local memory and not garbage-collecting after a request? It's HTTP so there should be no persistence at the web framework level (i.e. in Rails). It should manufacture a request, send it, and move on to the next one, shedding all the local variables made in the process. If your memory footprint is increasing while your real load is remaining the same, that's bad. If you're storing the same object in memory in 5 different places, that's bad -- but not that big a deal so long as they're all gone when the request has been served.(Flamebait P.S. -- save memory, kill Rails.) |
Who do you use for stock market data? | ced: Many years ago I looked into the problem, but for the Canadian market. We couldn't find a service with an API, so we took one of those 15$/month paying services that gives you some Java software to "analyze" the data (Stockwatch). I used a packet sniffer (Etherreal?) and reversed out the protocol. I used Python for the actual software. They don't really mind you doing that if you're paying already, so it was fairly easy to do, even for me who had no experience. |
Who do you use for stock market data? | charlesju: If your application can tolerate a day's delay then perhaps you should look into just grabbing the XML files from Yahoo! Finance. They let you download the history of any of their stocks and use in your own code.For example: http://finance.yahoo.com/q/hp?s=AAPL&a=08&b=7&c=..., and click on the download Spreadsheet link at the bottomupdown.com, an investing startup that really likes advertising to me on Facebook, uses these guyshttp://www.quotemedia.com/They seem to offer live quotes, but I cannot personally vouch for their services. |
ASK HN: Master degree in CS - USA or Sweden? | charlesju: Maybe I'm a little biased but I'm going to pick the USA, and in particular, probably California. Here are 3 major reasons:1. Perfect weather2. Silicon Valley3. We have a good portion of the top technical schools in the world (Stanford, Cal-Tech, Harvey Mudd, UC Berk, UCLA, USC), I think proportionally more than any other area at least.But ultimately it depends on what you want to do. I personally go to UCLA, it's an awesome school, the faculty is great, the curriculum is challenging, and everyone is very friendly. I would recommend it, contact me if you want more information, charlesju[at]g-m-a-i-l(dot)com |
On scalability and memory footprint | ericb: If you're building a fairly standard web app you probably shouldn't be worrying at this stage. Keeping memory usage low does not mean a significant speedup necessarily. It means your memory usage will be low. Sometimes you trade one thing for another depending on what you're doing.When the app is written, if you run a load test (or you can let your users be your load test, like Twitter), there will be a bottleneck for some n of users. Remove this bottleneck, which could be cpu, database, memory, connections, bandwidth, etc., and there will be a new bottleneck at some > n users. Rinse, lather, repeat.If you optimize now, you're most certainly optimizing the wrong thing. When I load tested my first production rails app, I found cpu was the first bottleneck I hit, not memory. |
Good C (not C++) code for reading/learning? | dchest: Git? |
ASK HN: Master degree in CS - USA or Sweden? | pmjordan: I guess it heavily depends on how much you're planning to spend. I'm not sure if the EU-wide tuition equality is already in place for Bulgarian and Romanian nationals, but if it is, that will make Sweden substantially cheaper than the US, unless you can get some kind of grant or scholarship.EDIT: If you're planning to go to a top university, the US or the UK are probably good places to go. Unfortunately, the Times' university table http://www.timeshighereducation.co.uk/hybrid.asp?typeCode=24... seems to be down at the moment. |
On scalability and memory footprint | Hoff: Arguing performance and scalability and footprint can be less than fruitful; a distraction.If you're serious about this, build your test cases, and benchmark.But before you invest here, ensure you have nothing better to do with your time, and ensure that the probable payback can be justified against the aggregate investment; against the costs of the testing and of the migration. And nothing better to debate, for that matter. |
ASK HN: Master degree in CS - USA or Sweden? | Ras_: Sweden/Finland: Free tuition. Only cost comes from the obligation that you must be a member of the Student Government/Union. That's about $100 / year.
Living is more expensive than in the US.If you are Bulgarian as your profile states, you come from inside the EU/EEA area, thus also Danish universities would be free for you.If you want to build best networks for business, get into top universities in the USA. Tuition isn't that much better.
Start-up scene is also nearly non-existent in Scandinavia - severe lack of funding opportunities.If you plan to work in the USA, go to a US-based university. If in EU-area... |
Good C (not C++) code for reading/learning? | bayareaguy: It's a little dated now but the Tcl/Tk source is very good. I'd also recommend the FreeBSD source tree. |
Good C (not C++) code for reading/learning? | xpaulbettsx: GNOME code and the Linux kernel are both pretty good examples - writing a well-structured, small GTK+ app will do wonders for your C skills |
On scalability and memory footprint | anotherjesse: I run userscripts.org, a rails site which runs on a single serverbeach box.To keep memory usage low, I find recycling mongrel processes via monit can help a bunch.Before monit, my mongrels would hit 2GB quickly, after monit with a rule to restart when they hit over 100MB, my memory usage is around 800MB for 15 mongrels. (I'm assuming you are using HAProxy or a similar balancer that can deal with changes of availability).http://userscripts.org/articles/2-scaling-a-rails-siteAnother useful tip is make sure your queries aren't doing stupid stuff. A long time ago I had integrated Beast (a rails forum project) into my site. Unfortunately it was loading EVERY topic on the forum index page, which was resulting in slowness as well as large jumps in memory usage. (The culprit was a .last method that caused all the records to load and then grab the last value)So - I tend to agree with "don't worry" because you can "patch" over memory usage pretty easily.My site is currently getting 17req/s on a single box - it is never what you think will be the issue that you have to fix. |
ASK HN: How to deal with journalists? | yarc: Don't expect it to last. Don't expect special treatment. But if you can consistently provide a service or genuine analysis then let the world come to you. |
Good C (not C++) code for reading/learning? | reginaldo: One piece of code I found particularly useful was the old tftp. It's small enough yet very instructive. |
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