Last updated: 01/01/2019

Well, maybe I’m not as popular to be frequently asked about so many things; however, you can treat this page more like an aggregator for some of my handy answers (personal and technical).

If you have a question that was not listed on this page, please do not hesitate to get in touch with me. I will also try to let myself be known in various posts of this blog.

People change on average every 7 years (I think), that is why I keep above the “Last Updated” note.


  1. Why did you start this blog?
    I tried to answer this question in depth in my first post.
    In short, I like to write, and I would feel unfulfilled keeping all the exciting stuff locked in my mind without sharing it with someone who might greatly benefit from it.

  2. What is your life goal/direction?
    To be happy with what I do for the living and contribute as much as I can to the constantly developing world, leaving the universe in a better state in the end.

  3. Your motto?
    It changes with time, depending on my situation. Currently, I think my favourite one is Done is better than perfect that helps me to fight procrastination and perfectionism.

    You can find the list of all my favourite thoughts here (updated regularly).

  4. Answer in one word: What is the must-have for success?
    Focus.

  5. Life influencers?
    Mike Shinoda, Siraj Raval, Elon Musk, Naveen JainJordan B Peterson, Gary VaynerchukTim Ferris, Brian Tracy, Grant CardoneNapoleon HillJakub Mrugalski (🇵🇱), Mirosław Burnejko (🇵🇱), Maciej Aniserowicz (🇵🇱), Andrzej Krzywda (🇵🇱)

  6. Preferred source of Data Science news?
    DataTau (Hacker News like. Still growing, but I prefer it mostly for the concise design. To make it easier to read, I have created a dark theme for it once)
    Inside AI (daily newsletter. You can also check the recent issues)
    Towards Data Science (Medium like)
    Data Science Central

  7. Any general recommendation for “nerd” news?
    Hacker News which has the greatest community I have ever seen. Not finding a suitable dark theme for the website, I wrote my own once. Apart from it, I enjoy visiting Ars TechnicaSlashdot, TechCrunchThe Hacker News and dobreprogramy (🇵🇱) (all the mentioned sites are mostly free of clickbait and offer overgrowth of content over the form).

  8. Can you recommend me a single (ultimate) Data Science cheatsheet?
    My notebook. 🙂
    You can actually check my Pinterest profile, where I have collected the best infographics/cheat sheets.

    If it comes to other online resources, Chris Albon did a great job there. 

  9. Python/R?
    I always say that in Data Science it is the most important to train logic and math. Later, the language is like a suit you wear, and in my case, I mostly reach for Python. I found some senior R developers, who claimed that they would start with Python if they got another chance (mainly for the reason of ML-based resources); however, I’m jealous of their pretty looking RStudio.

    Once I found a great comparison between the languages in a single presentation, which might give you a nice contrast between both of the options.

    You may also want to try and combine both languages to use the best part of each. I found this blog post to explain how to do it most conveniently.
    tl;dr:
    • (R) reticulate for connecting R with Python
    • (R) tidyverse for data exploration
    • (Python) scikit-learn/TensorFlow for ML and DL
    • (R) ggplot2 for visualisation
    • (R) R Markdown for reporting and Shiny for web apps

  10. IDE?
    Jupyter Notebook for the beginning and the reason of maintaining a well-documented code. Moreover, it runs in a browser and nicely displays your shiny visualisations, which makes it stand out for Data Science.

    Personally, I enjoyed using classical Sublime Text with few plugins, but nowadays, I am trying to switch to VS Code, which gets pretty nice reviews, especially from Pythonic community.

    If you are not happy with those, you can also try Spyder as a free solution and PyCharm for professional development.

    If you want to try Jupyter, Spyder and VS Code, just install a famous Anaconda Distribution to have a clear overview and ease of management over your tools. 

    EDIT: Last time, Google Colaboratory is more and more popular choice that requires no setup and runs entirely in the cloud. As such, it is one of the best free options for running large deep learning models (don’t forget to change runtime type to GPU).

  11. Windows / Linux / macOS?
    I definitely see some pros and cons in each of these systems. Because of my familiarity with Windows tools and their unique availability on this OS, I cannot decide and don’t plan to switch yet; however, if I would have to migrate, I would choose Linux, as I don’t want to be neurologically hooked to Apple’s ecosystem. By the way, one of my favourite Linux distros are Deepin, Tails and Kali Linux 😈.

    Microsoft wrote most of their software in WinAPI, and the majority of the programmers don’t like to code in that. Nowadays, we also have UWP, which requires another department and becomes a source of struggles to go through. Simply, since Windows 95 there are so many hidden functions here and there (such as 4 control panels), that the system cannot be stable, like macOS. I hope that one day Microsoft will finally reconstruct the entire system and develop a single API.

  12. You look like you must be spending a lot of time on YouTube. Videos of whose authors you tend to watch the most?
    Haha, yeah, that is true. It changes from time to time, but I will try to give my current preferences. Maybe let’s go by the categories:
    • Data Science: Siraj Raval, sentdexTwo Minute Papers
    • Math: 3blue1brown, Numberphile, Domain of Science, Welch Labs, Think Twice,
    • Productivity/Business: Charisma on Command, FightMediocrityMiroBurn (🇵🇱), Devstyle (🇵🇱), Andrzej Krzywda (🇵🇱),  Akademia Bogactwa (🇵🇱), Wojna Idei (🇵🇱)
    • Science: Kurzgesagt, What IfMinuteEarth, Life Noggin, AsapSCIENCE, minutephysics, PrimerSciFun (🇵🇱), Uwaga! Naukowy Bełkot (🇵🇱)
    • Tech News: LinusDave Lee, Techquickie
    • IT: The Coding Train, Kevin Naughton Jr., LiveOverflowComputerphile, Pasja Informatyki (🇵🇱), Niebezpiecznik (🇵🇱)
    • Music: I rather prefer SoundCloud and my personalised newsfeed
    • Entertainment: PewDiePieAlan BeckerLevel UPvideogamedunkey

    I don’t know, maybe you got some good recommendations for me. Please let me know 🙂

  13. Ultimate mobile/web apps to kill the time?
    • Brilliant – app that I do not feel guilty wasting my time with and paying to be a premium subscriber. It’s part of my “Three Goals” programme
    • CodeSignal and HackerRank – web apps that can highly benefit your programming skills (especially for the interview kind of tasks)
    Elevate – used daily can significantly improve math, reading, writing, speaking, and listening
    Puzzlerama – stock of puzzles
    SoloLearn – mobile programming university
    Materialistic – Hacker News – great looking tech news that I can read for hours

  14. Favourite entertainment website?
    SoundCloud. I realise it is not only my main entertainment website since 2012 but a permanent source of joy through everyday fresh tunes that I like.  Because of this site, I was able to find a lot of artists, friends and sources of influence, such as CruciA or synx that play a huge part in my life.
    In my free time, I want to be more active on the site and start sharing more of my own creations.

  15. Favourite TV show?
    I don’t usually watch any TV series, but Mr. Robot gave me a lot of a great time of reflection.

  16. Who is your favourite game character?
    Cannot decide between Sonic and Link, but Link was definitely a significant source of inspiration in my life – the hero to follow and take inspiration from.
    Cool fact: I have included him in one of my LinkedIn posts and 404 page of this website. 🙂

  17. pyXelr – your nickname. How should I even read that?
    As everyone out there I used to have many nicknames before I decided for the ultimate one. I’ve ended up with pyXelr because I like pixel art and it sounds fancy, so there is no need to look further. Initially, it had to be pyXel, but Gmail required 6 characters to register your mail account. This is why there is that little “r” at the end. 🙂

    I leave everyone with a free choice of reading it, as even I tend to spell it randomly. For now, if I would have to introduce this nickname to an online stranger, I would say “pixel” not to cause long time debates on adjusting his tongue.

  18. I want to be like you, what should I do?
    Okay, let it be the last question, I’m tired. I may sound like Gary Vaynerchuk, but don’t waste your time trying to be like anyone else.  Moreover, do not compare yourself to others as you can only harm yourself this way. Let yourself have some influencers, but do not copy them. Everyone is beautiful in their own being, and this is why the world can advance, by brainstorming through unique views and forming the exceptional solutions.