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The most important projects done by Ciro Santilli by Ciro Santilli 40 Updated 2025-07-16
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Ciro Santilli has sometimes wasted time with low impact projects such as those listed at Ciro Santilli's minor projects instead of doing higher impact projects such as those mentioned at: Section "The most important projects Ciro Santilli wants to do".
But maybe "Everything you did brought you where you are now." applies, maybe it is during the "low impact activities" that one gets the inspiration and experience required for the "high impact ones".
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The most important projects Ciro Santilli wants to do by Ciro Santilli 40 Updated 2025-07-16
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They are sorted in order of "most likely to get done first".
Top one: OurBigBook.com.
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The next big thing by Ciro Santilli 40 Updated 2025-07-16
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If you are going to live, you might as well chase one of them.
You might not achieve them in your lifetime, but you never know. At some point, the pieces just "fall into place", and they happen.
And they will all come from deep tech.
Ciro Santilli would like to contribute to them. but this is a bit less realistic than software projects.
But who knows? Maybe he can code some stuff in those areas.
And one can at least have some fun by learning deeply about those subjects.
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The best articles by Ciro Santilli by Ciro Santilli 40 Updated 2026-08-21
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These are the best articles ever authored by Ciro Santilli, most of them in the format of Stack Overflow answers.
Ciro posts update about new articles on his Twitter accounts.
A chronological list of all articles is also kept at: Section "Updates".
Some random generally less technical in-tree essays will be present at: Section "Essays by Ciro Santilli".
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How to contact Ciro Santilli by Ciro Santilli 40 Updated 2025-12-25
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Ciro Santilli is very happy to meet people with related interests, he really loves his like-minded online friends. Even if you don't have something a specific goal in mind for the contact, please just say hi.
To contact Ciro publicly about any general subject that is not covered in a more specific GitHub repository, including saying hi or suggestions about his website either:
Publicly viewable contact is preferred if possible to more effectively share Ciro's wisdom with the world.
But if you feel more comfortable with private contact, no problem, either:
For other less good methods that will also likely work, use direct messages of the following profiles from under Section "Accounts controlled by Ciro Santilli":
Ciro's Twitter DMs are also open, but note that Ciro receives endless Chinese language SPAM there which Twitter is doing nothing to combat, so it's not as reliable.
If you are a privacy freak or are going to tell Ciro state secrets Ciro has this GNU Privacy Guard public key: pubkey.gpg, but it's not something that he has ever really used.
Disqus comments were removed from his website in 2019-05-04, a manual dump is available here, removal rationale at: why Ciro Santilli removed Disqus comments from his website in 2019-05-04.
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Accounts controlled by Ciro Santilli by Ciro Santilli 40 Updated 2026-03-05
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Ciro Santilli controls the following accounts.
With non-trivial activity:
Trivial or no activity:
Profiles without URLs (OMG...):
  • Discord: username cirosantilli, previously cirosantilli#8921
Lost or deleted:
Accounts in Chinese websites. These accounts might be banned or altered or offer other limitations, so Ciro only communicates briefly through them. All communication through those channels should obviously be assumed to be compromised:
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Cirism by Ciro Santilli 40 Updated 2025-07-16
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Welcome to the wonderful world of Cirism!
Followers of Cirism call themselves Cirists, and their primary goal in life is to obtain Cirocoins.
Enlightened Cirists donate money to the cause at: Section "Sponsor Ciro Santilli's work on OurBigBook.com". It is totally optional of course, your soul will just be eternally damned if you don't.
Ciro Santilli once proclaimed:
Thou shalt eat thy watermelon in the morning, and thy melon in the evening. Thou shalt not eat thy watermelon in the evening, nor shalt thou eat thy melon in the morning.
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cirosantilli.com by Ciro Santilli 40 Updated 2025-07-16
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Ciro Santilli's website is a dump of his brain, see also: braindumping.
However it won't remain like that for long, because it will be migrated to OurBigBook.com, and therefore become a brain dump of society itself.
Video 1.
Who Wants To Live Forever by Queen (1986)
Source.
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Ciro Santilli's skills by Ciro Santilli 40 Updated 2025-07-16
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Ciro Santilli's psychology and physiology by Ciro Santilli 40 Updated 2025-07-16
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Ciro Santilli's energy throughout the day varies as follows:
  • morning: highest
  • 11AM: peak exercise performance
  • after lunch: brain death. Possibly due to Ciro's partial Spanish descent?
  • late afternoon and evening: can do some stuff
Ciro has low tolerance to sleep deprivation which makes him very irritable, and low ability to sleep if there is any light. It must have to do with those damned ganglion cell photoreceptors. On the other hand, Ciro Santilli's wife can sleep without any problems with some morning light! It is definitely genetic. Ciro conjectures that people from very Northern parts of the world must have a gene that allows them to sleep even if there is some light, while more equatorial people don't. Maybe: pubmed.ncbi.nlm.nih.gov/33049062/
Ciro has mild olfactory synesthesia for star anise (八角, bajiao), which is widely used in Chinese cuisine and makes Ciro think uncontrollably of the color blue. Ciro does not have any other known synesthesias. He is also prone to nerd sniping form time to time.
Ciro is a reptilian-like being with cold hands and feet and low blood pressure. For this reason he believes that he will die of cancer or some respiratory problem. If the Chinese government doesn't get him first that is. This also partly explains why Ciro is not a big fan of swimming.
Besides Chinese food, Ciro really likes eating fruits and roasted nuts, maybe partly because he was born in Brazil, and partly because of monkey nature, see his Chinese name. At home he is known as "水果大王" (the big king of the fruits). Ciro is also a sucker for yoghurt (natural without added sugars and full fat, fat-tree yoghurt is terrible, often eaten with fruits). Ciro's "favorite drink" could be tonic water with freshly squeezed lemon. Tied with fresh fruit juices. Chocolate-wise, although not a huge fanatic, a Lindt dark chocolate with whole hazelnut pieces bar will do the job.
Ciro does not like receiving or giving gifts on expected social situations like birthdays or Christmas. Ciro believes that every day is equally precious, and can be a day to give, be it through awesome open source software contributions, or if you find something that your friend will like
Ciro has some respiratory allergies. When he was around 5, he had relatively serious asthma crisis which scared his parents to death. Throughout his life, he appears to be allergic at an intermediate level to: mold or dust mites (or whatever it is that old books/pillows have), cats (itching on touch), hay fever (in May in the UK, likely grass pollen). But even outside of hayfever season, Ciro's nose is constantly either running in the cold, or often partially blocked while sleeping throughout the year. Ciro believes however that this also gives him higher resistance to viral infections, since it has been many many years since he had a cold/flu, and when everyone in the office is going down with it, he's just fine. Ciro wonders if his active immune system will actually kill off cancers early, which he ranks as his most likely causes of death, along with respiratory and gastro-intestinal problems. Ciro has low blood pressure and cannot get fat, so cardio vascular problems seem much less likely.
Ciro is generally democrat due to his high compassion level. He believes that politics is highly genetically determined, and that just like you enter a room full of people and immediately like some and dislike others, the same goes for politics. People just vote for whoever they want to see more of because their way of speaking makes them feel good. There is not rationality involved in it at all.
Ciro self diagnoses a slight graphomania in the early 2020's. This is largely what led him to create OurBigBook.com, and contribute to Stack Overflow. Literature Nobel Prize laureate Naguib Mahfouz also suffers from the condition however, so maybe good can also come out of it:
If the urge to write should ever leave me, I want that day to be my last.
When Ciro was quite young, maybe around 7-10, when he got very angry or sad for some stupid reason (bullying perhaps? Ciro forgot), he would have a psychosomatic manifestation: his spine would become visibly curved sideways (scoliosis). While writing this paragraph, Ciro Googled it, and found e.g. medium.com/@michaelrosen_94192/the-root-cause-of-scoliosis-5c461002b634 that describes:
The Root Cause of Idiopathic Scoliosis
It is proposed that Adolescent Idiopathic Scoliosis (AIS) is a condition created by emotional stress. Evidence is presented that unresolved emotional stress can cause unbalanced tensions in the fascia and growing muscles that gradually deform the spinal column.
so it is a somewhat well known thing! Incredible. Can you imagine the level of the passions that lead to such physical deformations? But of course, it was all for nothing.
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Ciro Santilli's drug experiences by Ciro Santilli 40 Updated 2025-07-16
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Ciro Santilli never did any illegal drugs, because he:
so don't expect any amazing stories here.
Like LDS believers, Ciro never drinks coffee nor smokes, and only drinks alcohol and tea sparingly, because they are all addictive drugs and bring no net increase of energy and concentration.
Ciro prefers to only enjoy a glass of tea when going out cycling on a cold day (Earl gray, with milk, no sugar), or get a half pint of beer when going out with friends to a pub.
Ciro only got reasonably drunk twice on his life:
  • once when he was quite young, likely pre-10 years old, while visiting an uncle's home, and adults were having a very nice sweet and thick type of alcoholic cocktail, and Ciro drank a bit too much and that made him really really stupid
  • once while studying at University of São Paulo, somehow someone was giving free beers at one of the parties (at which Ciro practiced Cirodance). And since Ciro had always been a cheap-ass, he thought, hey, this is a good chance to try it out. Ciro remembers that this made him a bit euphoric, active, very stupid, and a bit horny (though of course, he got no pussy as usual).
Later in life, around the time of his wedding, there were guests around all the time, and he was drinking beer with them all the time. Then one day, during lunch, Ciro felt a weirdly strong desire to drink one more pint. It was at this point that Ciro realized first-hand what mild, but real, alcohol addiction felt like, and he didn't get that drink, and swore from then on to never drink more than one glass a week, and only with friends at a bar after work. Richard Feynman tells a very similar story on his book Surely You're Joking, Mr. Feynman chapter O Americano, Outra Vez!, see: Section "Richard Feynman's drug use".
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Ciro Santilli's biography by Ciro Santilli 40 Updated 2026-09-12
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Maybe Ciro Santilli should do something useful and remarkable so that someone might actually want to read his biography in the first place. But hey, procrastination.
Ciro Santilli was born in Brazil in the small/medium city of Rio Claro, São Paulo (~200k people in 2020) in the State of São Paulo in 1989 AD.
When he was 3, the family moved within Rio Claro to Av. 44 - Parque Universitario, Rio Claro - SP, 13504-360.
In 1995 the family moved to Jundiaí (Rua José Milani, CEP 13207-691) for his father's work. He played a lot on the streets. Ciro learned to cycle there on a slight downhill. He was mildly bullied by some kids on the street. He played NES games that were far too hard for him which made him made and required his parents to call the teenage neighbors to beat. The neighbors had some DOS games which felt like mystery and magic.
In 1997 family finally moved to Santos, São Paulo, Brazil again for his father's work.
In 2010, as mentioned at Section "Ciro Santilli's formal education", Ciro as admitted in a double degree program at the École Polytechnique, France, where he stayed until 2013. Going to France was a mind blowing, life changing event.
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Ciro Santilli's Open Source Enlightenment by Ciro Santilli 40 Updated 2025-07-16
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Firstly, in 2012, while he was at École Polytechnique, Ciro Santilli was introduced to LaTeX (thank God for French mathematical obsession), and his mind was blown:
Ha, so I can write my own books, and so can anyone, for free?
he though. Why isn't everyone doing that!
One particular event stood out: Ciro made a small change to his teacher's course material, who blessed be him (dude's a legend, Ciro just noticed he has some Chinese publications with another French dude, e.g. www.amazon.co.uk/高效算法-应试与提高必修128例-克里斯托弗-Christoph-Durr/dp/B078SJQPVK "High-efficiency algorithm competitions 128 examples", did he write it the Chinese himself?? Must be of course to complement the notoriously low French professor salaries), made it available, and then Ciro gave him back the .tex file. Ciro was just a bit worried about how the teacher would be able to tell what he had changed in the file to validate the change. The teacher just said of course, "no problem, I'll just use diff". Ciro had never heard of diff. Let alone Git of course, though yes, this was a bit early in Git's history version control systems had been around since forever of course. This was 2011 or 2012, about 4 or 5 years into a superior education curricula with various courses involving computers, some requiring quite a lot of "fill these empty functions" style programming. Education is a joke. Anyways, this was a prelude to exactly what Ciro wanted to do in OurBigBook.com. This might have been the one actually: webia.lip6.fr/~durrc/Iut/Notes580.pdf
Not long afterwards, Ciro started playing with Linux. Until then, Ciro had had some contacts with the mysterious operating system at university, and was a bit puzzled what the point of it was! He clearly remembers:
University should be forced to use only open source software and hardware in undergrad teaching courses by law BTW.
Then came an Ubuntu live disk on his own machine, and finally a measly 40GB dual book partition in a Microsoft Windows machine on a laptop. At first, it took a lot of time to learn all the crazy new terminal stuff! Yes, at this point, Ubuntu was already usable enough without the terminal, an accomplishment actually. But as a programmer, Ciro felt obliged to learn. Many hours were spent reading man pages at the library. But it all just felt so right, and sometimes powerful... true wizardry.
And ten years later, Ciro was seriously considering buying a computer without Windows pre-installed. He had not used Windows a single tie on a personal machine even once in those ten years!
Finally, to finish things off Ciro found two websites that changed his life forever, and made be believe that there was an alternative: Stack Overflow and GitHub.
The brutal openness of it all. The raw high quality content. Ugliness and uselessness too no doubt. But definitely spark in a sea of darkness.
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Ciro Santilli's projects by Ciro Santilli 40 Updated 2025-07-16
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A summary of minor projects is given at: Ciro Santilli's minor projects.
This section is a dump for anything else, to keep those sacred first sections that show on the top of the homepage clean.
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Essays by Ciro Santilli by Ciro Santilli 40 Updated 2025-07-16
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Ciro Santilli's hardware by Ciro Santilli 40 Updated 2025-07-16
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One day, someone will invent a way to take the hash of a piece of hardware and see its history log, like software engineers do with version control. Until then, this is as close as you can get.
Ciro one day guessed that hardware would certainly be a slang for something naughty, and yup, here we are: www.urbandictionary.com/define.php?term=Hardware, drug paraphernelia. Read on!
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Ciro Santilli's cooking by Ciro Santilli 40 Updated 2025-07-16
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Art young Ciro Santilli consumed by Ciro Santilli 40 Updated 2025-07-16
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Maybe those are genial. Maybe not. Nostalgia is just too strong to discern. Ciro still goes back to them for rest.
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Artist by Ciro Santilli 40 Updated 2025-07-16
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ASCII art by Ciro Santilli 40 Updated 2025-07-16
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It should be a crime to automatically generate ASCII art from images.
For some ASCII art in the Bitcoin blockchain see: ASCII art.
        z

        ^
        |    *------*
        |   /|      /
        |  / |     /|
top -------*------* |
        |  | *----|-*
        |  |/     | /
        |  |      |/
bottom ----*------*
        |  |      |
        +--|------|-----> y
       /   |      |
      /    |      |
  x  /     |      |
    v
          left   right
Code 1.
3D cube plot ASCII art by Ciro Santilli (2021)
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Pinned article: Introduction to the OurBigBook Project

Welcome to the OurBigBook Project! Our goal is to create the perfect publishing platform for STEM subjects, and get university-level students to write the best free STEM tutorials ever.
Everyone is welcome to create an account and play with the site: ourbigbook.com/go/register. We belive that students themselves can write amazing tutorials, but teachers are welcome too. You can write about anything you want, it doesn't have to be STEM or even educational. Silly test content is very welcome and you won't be penalized in any way. Just keep it legal!
Video 1.
Intro to OurBigBook
. Source.
We have two killer features:
  1. topics: topics group articles by different users with the same title, e.g. here is the topic for the "Fundamental Theorem of Calculus" ourbigbook.com/go/topic/fundamental-theorem-of-calculus
    Articles of different users are sorted by upvote within each article page. This feature is a bit like:
    • a Wikipedia where each user can have their own version of each article
    • a Q&A website like Stack Overflow, where multiple people can give their views on a given topic, and the best ones are sorted by upvote. Except you don't need to wait for someone to ask first, and any topic goes, no matter how narrow or broad
    This feature makes it possible for readers to find better explanations of any topic created by other writers. And it allows writers to create an explanation in a place that readers might actually find it.
    Figure 1.
    Screenshot of the "Derivative" topic page
    . View it live at: ourbigbook.com/go/topic/derivative
    Video 2.
    OurBigBook Web topics demo
    . Source.
  2. local editing: you can store all your personal knowledge base content locally in a plaintext markup format that can be edited locally and published either:
    This way you can be sure that even if OurBigBook.com were to go down one day (which we have no plans to do as it is quite cheap to host!), your content will still be perfectly readable as a static site.
    Figure 2.
    You can publish local OurBigBook lightweight markup files to either https://OurBigBook.com or as a static website
    .
    Figure 3.
    Visual Studio Code extension installation
    .
    Figure 4.
    Visual Studio Code extension tree navigation
    .
    Figure 5.
    Web editor
    . You can also edit articles on the Web editor without installing anything locally.
    Video 3.
    Edit locally and publish demo
    . Source. This shows editing OurBigBook Markup and publishing it using the Visual Studio Code extension.
    Video 4.
    OurBigBook Visual Studio Code extension editing and navigation demo
    . Source.
  3. https://raw.githubusercontent.com/ourbigbook/ourbigbook-media/master/feature/x/hilbert-space-arrow.png
  4. Infinitely deep tables of contents:
    Figure 6.
    Dynamic article tree with infinitely deep table of contents
    .
    Descendant pages can also show up as toplevel e.g.: ourbigbook.com/cirosantilli/chordate-subclade
All our software is open source and hosted at: github.com/ourbigbook/ourbigbook
Further documentation can be found at: docs.ourbigbook.com
Feel free to reach our to us for any help or suggestions: docs.ourbigbook.com/#contact
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