Essays on programming, mathematics, and technical writing.
I recently stumbled upon a nice blog post titled Childhood Computing. It made me think about my own childhood computing experience. I am much older than the author of the aforementioned post, but like them, I too love computers. I have for most of my life. In…
This is going to be a rant about modern web design practices. But before I get to that, let me begin with a familiar principle from the world of cryptography. Among software developers, and especially among those who work on security-sensitive systems, there i…
Let me share a very silly story from roughly 18 years ago! In 2008, I joined RSA, the network security company named after the initials of the inventors of the RSA algorithm, Rivest, Shamir and Adleman, who were also the founders of RSA, the company. There was…
Commenting Guidelines comments section, carefully maintained and curated by the author of this website. When commenting on this website, please keep the following points in mind: comments section. comments section is a sure way to ruin this carefully maintaine…
It is a commonly held opinion that educational institutions could do more to improve the pedagogy of mathematics. This is especially applicable to primary and secondary schools, where students are first exposed to mathematics as a formal subject, along with ot…
Last evening, a short blog post appeared in my feed reader that felt as if it spoke directly to me. It is Chris Morgan's excellent post I've banned query strings. Contents Wisdom on the Web Wander on the Web Misfeature Broken URLs Qualms Conclusion Wisdom on t…
Wander Console 0.6.0 is now available. This is the sixth release of Wander, a small, decentralised, self-hosted web console that lets visitors to your website discover interesting websites and pages recommended by a community of independent website owners. To…
Yesterday, I switched my website from RSS feeds to Atom feeds. In case you are wondering whether you have somehow landed on an ancient post from 2010, no, you have not. Yes, this is the year 2026, and I have finally switched from RSS feeds to Atom feeds. Yes,…
QuickQWERTY 1.2.3 is now available. QuickQWERTY is a web-based touch typing tutor for QWERTY keyboards that runs directly in the browser. This release includes two small bug fixes. In the previous release, QuickQWERTY source code management moved from GitHub t…
I learnt touch typing about two decades ago when I was still at university. Although I took some typewriter lessons as a child, those lessons did not stick with me. It was at university, when I found a Java applet-based touch typing tutor on the web, that I re…
This is my fourth set of monthly notes for this year where I write down interesting facts and ideas I have explored during my spare time. There were three things in particular that occupied my leisure time this month. First, I managed to learn the proof of Tut…
Typically a Git remote contains a single URL. For example, when we clone a repository, a remote named origin is automatically created and its URL is set to the location of the upstream repository. For example: $ git clone -q https://codeberg.org/spxy/spica.git…
QuickQWERTY 1.2.2 is now available. QuickQWERTY is a web-based touch typing tutor for QWERTY keyboards that runs directly in the browser. This release includes two important changes. First, a longstanding bug in the practice pane has been fixed. While practisi…
Wander Console 0.5.0 is out. It is the fifth release of Wander, a small, decentralised, self-hosted web console that lets visitors to your website explore interesting websites and pages recommended by a community of independent website owners. To try it, go to…
Wander Console 0.4.0 is the fourth release of Wander, a small, decentralised, self-hosted web console that lets visitors to your website explore interesting websites and pages recommended by a community of independent website owners. To try it, go to susam.net…
This is my third set of monthly notes for this year. In these notes, I capture various interesting facts and ideas I have stumbled upon during the month. Like in the last two months, I have been learning and exploring algebraic graph theory. The two main books…
I ran a small experiment with Git hosting behaviour using two demo repositories: cuppa: The original repository. muppa: Fork of cuppa with questionable changes. Name Codeberg GitHub cuppa codeberg.org/spxy/cuppa github.com/spxy/cuppa muppa codeberg.org/spxy/mu…
Wander 0.3.0 is the third release of Wander, a small, decentralised, self-hosted web console that lets visitors to your website explore interesting websites and pages recommended by a community of independent website owners. To try it, go to susam.net/wander/.…
Wander 0.2.0 is the second release of Wander, a small, decentralised, self-hosted web console that lets visitors to your website explore interesting websites and pages recommended by a community of independent personal website owners. To try it, go to susam.ne…
I have put together a small tool to explore the small web of personal websites. It is called Wander. Please visit susam.net/wander/ to try out my Wander console. If you have your own website, please consider joining this community by hosting your own Wander co…
Wander 0.1.0 is the first release of Wander, a small, decentralised, self-hosted web console that lets visitors to your website explore interesting websites and pages recommended by a community of independent personal website owners. Anyone with a personal web…
I have always used the git checkout and git reset commands to reset my working tree or index but since Git 2.23 there has been a git restore command available for these purposes. In this post, I record how some of the 'older' commands I use map to the new ones…
HN Skins 0.4.0 is a minor update to HN Skins, a web browser userscript that adds custom themes to Hacker News and lets you browse HN with a variety of visual styles. This release introduces a small fix to preserve the commemorative black bar that occasionally…
HN Skins 0.3.0 is a minor update to HN Skins, a web browser userscript that adds custom themes to Hacker News and allows you to browse HN with a variety of visual styles. This release includes fixes for a few issues that slipped through earlier versions. For e…
HN Skins 0.2.0 is a minor update of HN Skins. It comes a day after its initial release in order to fine tune a few minor issues with the styles in the initial release. HN Skins is a web browser userscript that adds custom themes to Hacker News and allows you t…
HN Skins 0.1.0 is the initial release of HN Skins, a browser userscript that adds custom themes to Hacker News (HN). It allows you to browse HN in style with a selection of visual skins. To use HN Skins, first install a userscript manager such as Greasemonkey,…
Since last month, I have been collecting brief notes on ideas and references that caught my attention during each month but did not make it into full articles. Some of these fragments may eventually grow into standalone posts, though most will probably remain…
Since last month, I have been collecting brief notes on ideas and references that caught my attention during each month but did not make it into full articles. Some of these fragments may eventually grow into standalone posts, though most will probably remain…
Nerd Quiz #4 is the fourth instalment of Nerd Quiz, a single page HTML application that challenges you to measure your inner geek with a brief quiz. Each question in the quiz comes from everyday moments of reading, writing, thinking, learning and exploring. Th…
I remember how dismayed Kasparov was after losing the 1997 match to IBM's Deep Blue, although his views on Deep Blue became more balanced with time and he accepted that we had entered a new era in which computers would outperform grandmasters at chess. Still,…