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Juan Reyero
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I have published a new, better version of my book, The Hacker Ways.  Check it out at, or read online at  I've also started sharing the org-mode sources for those of you who might want to may want to derive teaching materials from it, or use it as a template for your book. Find the source at  Feedback is greatly appreciated.  

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Interesting pointer to a Common Lisp web developer's write up over at Hacker News:

You don't have to go all the way to full Common Lisp server-side development. At I wrote in CL the engine that computes and creates the personalized PDF maps of the sky, then built an sbcl custom core that's kept listening to a socket. I then manage the httpd communication with rather simple Python and AJAX, relying in flat files and static HTML. I am quite happy with the maintainability, and I got to use Lisp in the part where I could really take advantage of its power and speed.

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Fascinating article on how we are protected by an agency I won't mention (but that will be reading this, hello!): 

Please note that you are not supposed to worry if you don't have anything to hide.  Several friends who grew up in soviet block countries tell me this sounds familiar. 

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This is sooo coool! No better way to understand complex data than visualization, preferably on a map. After all, an estimated 2/3rd to 3/4th of our brain's cortex (where all the action is) is dedicated to vision, and we're really good at it (haven't seen any estimates for language, or numbers). You can stare at a list of 2,300,000 tuples of geographical coordinates and mobile OS until you're blue in the face, but you won't be any wiser until you see them on a map (some in blue, indeed).

Now is it just me, or is there a strong correlation between Blackberry use and oppressiveness of the local political regime?

Some countries are definitely more chatty/twittery than their otherwise very similar neighbor countries, perhaps correlated to the level of English use/familiarity.

Now why is Spain all Android, generally speaking, while most countries in Western Europe are all iOS, generally speaking?

Mirror, mirror on the wall, who's the chattiest of them all?

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Interesting discussion at Hacker News about todo lists and why they don't work.  The original article's recommendation ---move your todos to the calendar--- wouldn't work for me.  The root of the problem for me is the hubris of my self of yesterday claiming the right to decide what my self of today should be spending time on.  I need to write down things that need doing and can't be forgotten, but surely I am in a better position to decide what to do over the next hour now than I was yesterday.

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Interesting article by Sala-i-Martin (in Spanish) on the decline of Nokia and Blackberry despite their spending huge amounts of money in R&D.  He claims that the problem is that they spent the money in R&D instead of "innovation", whatever that means.  I'd say they were simply developing the wrong things.

Why was it again that we think object oriented programming is a good idea? It feels so natural, that you naturally evolve into a  maze of hidden states. Specially when you have multiple levels of inheritance, in no time you can be dealing with more magic than Dumbledore.  State is your enemy.  State lurking from the depths of a parent class is deadly. 

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There...  I have just built a star map poster commemorating Nelson Mandela's release from prison, and I've learnt quite a bit in the process.  Thank you for the idea, Ján!

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Yesterday I started building a gallery of #GreaterSkies posters of great occasions.  I started with one marking Martin Luther King, Jr.'s "I Have a Dream" speech.  I need ideas on how to follow from here; my boys tell me to commemorate the times when Barça won their most important titles, and that's probably OK, but I would like to be a bit more inclusive of less important stuff.  

So, what should I add?  What momentous time and place would you like to commemorate?  Political, cultural, sports,...  anything goes.  Even Barça.  Please comment and vote!

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I am trying to use twitter to promote my last venture, (it's my last, but I've been working on it, on and off, for two years now...)

Greaterskies builds you a beautiful, high-resolution PDF with thousands of stars as seen from a place and a time of your choice.  As when your baby was born, or when you got married.  It makes an awesome poster and a great present.  

Today, and for a limited time, I am giving it away for free to people who retweet the last tweet at

I would really appreciate if (a) you'd help me get the word out, and (b) you'd told me what you think about the promotion strategy.  Other than it's odd to use G+ to point to a twitter-based offer ;-)
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