Chat programs that don't have a proper web-only operation and force you to have a mobile phone, e.g. WhatsApp.
Heck, even Signal, which is supposed to be super secure and good for your privacy, forces you to disclose your freaking cell phone to all contacts! lifehacker.com/how-to-use-signal-without-revealing-your-private-phone-1818996580
What is my phone breaks? What if I don't want to have a fucking phone? What if I move countries and have to change the fucking number? Also evil but less because done by all: chat programs that can't send you an email if you don't see the message in X minutes.
European Union, time to force those evil companies to use support open standards like XMPP?
The solution to "how to prevent spam" is simple: your ID is a public key that you own the private key for. If you start getting spammed, generate a new public key, and send it to all contacts, and dump the previous ID.
Email by Ciro Santilli 37 Updated 2025-07-16
Ciro Santilli's email can be found by cloning one of his repositories on GitHub. It is also given at: Section "How to contact Ciro Santilli".
Scikit-learn by Ciro Santilli 37 Updated 2025-07-16
Examples under python/sklearn
. .venv/bin/activate
pip install sklearn matplotlib seaborn
As of 2021, last updated 2016, and python 3.5 appears to be mandatory or else:
RuntimeError: __class__ not set defining 'AbstractBaseUser' as <class 'django.contrib.auth.base_user.AbstractBaseUser'>. Was __classcell__ propagated to type.__new__?
which apparently broke in 3.6: stackoverflow.com/questions/41343263/provide-classcell-example-for-python-3-6-metaclass and pyenv install fails on Ubuntu 20.10, so... fuck. Workarounds at:but am I in the mood considering that the ancient Django version would require an immediate port anyways? Repo is at Django 1.0, while newest is now already Django 3. The Rails one is broken for the same reason. Fuck 2.
Ruby on Rails by Ciro Santilli 37 Updated 2025-07-16
The only reason why Ruby exists.
This web framework is pretty good as of 2020 compared to others, because it managed to gain a critical community size, and there's a lot of basic setup already done for you.
it is just big shame it wasn't written in Python or even better, Node.js, because learning Ruby is completely useless for anything else. As of 2020 for example, most Node.js web frameworks feel like crap compared to Rails, you just have to debug so much there.
Used in GitLab, which is why Ciro Santilli touched it.
Aufbau principle by Ciro Santilli 37 Updated 2025-07-16
Boring rule that says that less energetic atomic orbitals are filled first.
Much more interesting is actually determining that order, which the Madelung energy ordering rule is a reasonable approximation to.
City of London by Ciro Santilli 37 Updated 2025-07-16
The City of London is an obscene thing. Its existence goes against the will of the greater part of society. All it takes is one glance to see how it is but a bunch of corruption. See e.g.: The Spiders' Web: Britain's Second Empire.

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!
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
  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 5. . 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.
  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