#622 – April 20, 2025
most people have no idea
What is Entropy?
36 minutes by Jason Fantl
People say many things about entropy: entropy increases with time, entropy is disorder, entropy increases with energy, entropy determines the arrow of time, etc..but most people have no idea what it is. Jason provides a clear explanation of entropy across multiple disciplines.
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Ship Software That Does Nothing
5 minutes by Kerrick Long
In this post Kerrick advocates for shipping a blank page to production servers on day one, arguing that this approach addresses key infrastructure decisions early when risks are lowest. This strategy forces developers to establish crucial elements like deployment automation, testing, and continuous integration before adding actual features. By starting with nothing and incrementally adding functionality, teams can avoid the panic of a major deployment, get early user feedback, and systematically address risks in manageable pieces.
Every Caching Strategy Explained
8 minutes by SWE Quiz
Caching is one of the simplest concepts for devs to know. The article outlines five main caching patterns which offer different balances between read/write speed, consistency, and implementation complexity, with selection depending on specific application requirements like read/write patterns and consistency needs.
Building HOTP and TOTP from scratch
7 minutes by Doğaç Eldenk
Doğaç explains the fundamentals of One-Time Password (OTP) authentication systems, particularly focusing on HOTP (counter-based) and TOTP (time-based) methods. He details how both systems work through cryptographic algorithms that allow servers and clients to generate matching codes without transmitting the actual password, making them more secure than traditional authentication.
Talking To Your Mailserver Is Not as Hard as You Think!
6 minutes by Michael Lohr
Email is one of the oldest—and most resilient—forms of digital communication. At the heart of its modern infrastructure lies the IMAP protocol. In this post Michael explores the fundamentals of IMAP - how it works, how to interact with it directly using command-line tools like telnet and openssl, and why it's still such a powerful and flexible protocol today.
Why is there a "small house" in IBM's Code page 437?
20 minutes by Heikki Lotvonen
Dive deep into the history and mystery behind the house symbol found at position 0x7F in IBM's Code Page 437 character set from 1981. Heikki investigates several theories about the symbol's origin, including whether it was meant to represent a home computer, was borrowed from Wang terminals, or was actually intended to be a Greek delta symbol. Regardless of its original intent, the house character became widely used in PC ASCII art for its unique shape rather than its intended meaning.
And the most popular article from the last issue was: