Peteris Krumins
Peteris Krumins writes about Unix tools, Vim, bit hacks and programming, and also runs Browserling and its online tools.
What HN says
Commenters call the blog excellent and like his comics, though one finds the spammy 'Top Posts' links and the online tools sites odd.
Stats for nerds
316HN people shared it
335linked in comments
15Kstory points
Jan 2026last shared
Top posts on HN
- 1Low Level Bit Hacks You Absolutely Must Know7 people · 657 points · first shared 2009 · 171 comments on HN
- 2Good at programming competitions does not equal good on the job [video]7 people · 577 points · first shared 2015 · 166 comments on HN
- 3Browserling goes viral with cheap phone users trying to use WhatsApp6 people · 492 points · first shared 2017 · 222 comments on HN
- 4Here is why vim uses the hjkl keys as arrow keys11 people · 480 points · first shared 2012 · 98 comments on HN
- 5Using Fibonacci numbers to convert from miles to kilometers and vice versa1 person · 362 points · first shared 2024 · 129 comments on HN
- 6I am doing a startup (putting virtual machines on the web)2 people · 299 points · first shared 2010 · 103 comments on HN
- 7A Unix Utility You Should Know About: Netcat (2009)2 people · 286 points · first shared 2009 · 36 comments on HN
- 8A Unix Utility to Know About: lsof (2009)2 people · 279 points · first shared 2009 · 53 comments on HN
- 9We open-sourced 90 node.js modules at Browserling2 people · 277 points · first shared 2011 · 32 comments on HN
- 10My favorite regex of all time3 people · 274 points · first shared 2012 · 111 comments on HN
What HN people wrote when they linked it
- rubyn00bieAug 2020
Two things that helped me more than anything with "learning" vim and or ever wanting to use it:
1. Remap your "capslock" key to "escape." Vi was written using an ADM-3A terminal and its keyboard, which you can see here: https://catonmat.net/why-vim-uses-hjkl-as-arrow-keys has the escape-key in a sane place. On modern keyboards, if you can, remap "capslock" to "escape" when pressed alone, and "ctrl" when pressed with another key.
2. Make your leader key something easy like the comma character "," E.g. to make a horizontal split, I press (not including quotation marks) ",h" or ",v" to make a vertical one.
Once I did those two things it all made so much more sense... It's also great because most editors these days support vim bindings, so even if you don't want to use vim you can still benefit from its really-awsome-once-you-figure-it-out UX.
- ryanobjcMay 2014
On the partition side of things... not really. Usually you end up with coordinated failures of various types.
For example, lets say you run redundant networks. Are the physical paths diverse? What happens if someone trips on BOTH network cables? What happens if the redundant network is on the SAME switch hardware? What happens if yes you use two network switches, but they are hooked up to the same UPS? Or both UPSs are on the same circuit breaker?
The classic reference on this is from google: http://www.catonmat.net/blog/wp-content/uploads/2008/11/thatcouldnthappentous.pdf
There are a number of theoretical issues with these approaches, starting with the FLP result.
Also realistically, eventually all practical solutions fail, often due to user error.
- briandollDec 2012
Here's another list, sans product hype:
Unix command-line tools like awk and grep. Set operation commands are essential too (http://www.catonmat.net/blog/set-operations-in-unix-shell/)
Ruby/Python/Perl for more complex massaging and wrangling
Excel (yes, really) for quick stats and graphs, great 1st step in understanding what you have
D3.js for visualization
I've used R in the past, but I found I was trying to squeeze data into R models. D3 is pretty hard to grasp initially (I'm very much still learning) but I'm finding that it's helping me think through how to visualize the data I have, rather than just forcing it into one of a few standard charts.
- harperleeApr 2015
Great visualization (as the rest from http://setosa.io , go have a look)!!
I wonder, though: I learnt OLS as standard math / symbolic logic; but, if kids and students learnt from these visualization, would they be better off, or worse off?
Because, at least for me, it is difficult to reason about this and other visual math examples (whereas there are others that are great as demonstrations, as the integer proof in http://www.catonmat.net/blog/visual-math-friday/ , this one, regarding OLS, confuses me).
It probably depends a lot on each person. Out of curiosity, does this particular example give you insights? Which ones? How?
- TwisellJan 2021
Well I think the nice point of doing excercise in a web browser is that you can quickly switch to another tab and search for daring questions such as " by the way why on earth does this monstrosity want me to use hjkl? That don't make any sense!!!!"
https://catonmat.net/why-vim-uses-hjkl-as-arrow-keys
For a mostly data/SQL guy wanting to learn more about coding it still don't make much sense but at least I know why and I can move on. When I was trying vimtutor in a CLI interface I was less curious and more WTF F... this is pure madness kind of mood.
Dunno if I'll subscribe but nice first experience through this demo.
- kace91Oct 2019
I think there could be a huge market for a ux effort that brings the somewhat forgotten goodies of old modal editors into the modern world, combining them with new advances like fuzzy searching. I love vim, but it's appalling that we have so many historical baggage creating a gap for the users...
It's so obvious how vim's ergonomics are made for the [adm 3a keyboard](https://catonmat.net/images/why-vim-uses-hjkl/lsi-adm3a-full-keyboard.jpg) (location of esc, control, arrow keys, etc) and yet we keep making layers of customization or force ourselves to the standard instead of doing the very needed reboot.