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Hooks vs Callbacks vs Webhooks How do I use them and where is the difference? Photo by Dan-Cristian Pădureț The Unix programming philosophy is to do (just) one thing but do it well. Focusing on one core task is hard as developers see and feel their users' pain points and desires. To be able to focus on the core product but allow additional functions we … Read More »

Synchronous vs Asynchronous vs Concurrent vs Parallel What is the difference and why does it matter? Photo by Edurne Chopeitia on Unsplash We developers like to throw around terms that feel natural to us, but are technical terms that most non-developers don’t use in the same way. This article is aimed at all the poor souls who have to deal with us, e.g. product … Read More »

10 Robustness and Resiliency Design Patterns to Learn Today Software is correct if it acts as specified. It is robust if it can take a high load until it goes down. Software is resilient if it can go back to normal after a disruption. The disruption could be a power outage, a temporary network outage, a full disk, or … Read More »

How to use GPG Send and receive encrypted messages Having full control over encrypted messages is sometimes just nice and crucial in other situations and/or places in the world. GPG, the Gnu Privacy Guard, is a commonly used tool to encrypt, decrypt, and sign secrets. After reading this article, you will know how to use GPG. Let’s … Read More »

Library vs Service: 7 Arguments to consider Learn what the difference is and when to use which Shared code can be in a library or in a service. Image by Martin Thoma. Preventing code duplication is a software development principle called DRY — Don’t Repeat Yourself. DRY is important because duplicated code usually means way more code that needs to be maintained. If you … Read More »

The 7 Types of Cryptocurrencies You Must Know Coins, Utility and Security tokens, Stablecoins and NFTs: Bringing order to an ecosystem Categorization of the top 30 cryptocurrencies + some chosen ones. Image by Martin Thoma The crypto ecosystem grew rapidly in the past years — so rapid, that it’s hard for outsiders to even understand the various use-cases in that space. After reading this article, you should have some mental models to … Read More »

5 Applications of Digital Signatures Learn what they are and how they are used We use signatures to show that we have read a contract and want to do our part of fulfilling it. They serve two purposes: Expressing an intend and being able to prove to the authorities that this intend was expressed in case one of the parties does not follow the … Read More »

8 Techniques To Speed up Your Database “If everything seems under control, you’re not going fast enough” Photo by Christina Morillo (original). Thank you! Almost all web services for end-users have the need to store data. Almost all of them store them in a database. And quite a lot use a relational database like PostgreSQL, MySQL/MariaDB, or MSSQL. Database systems are pretty awesome because you can … Read More »

Scaling Vertically vs Scaling Horizontally Be smart or throw money at the problem Image by Martin Thoma The beauty of software development is that almost arbitrary many can profit from a developer’s work. Web services such as Facebook or YouTube have several hundred developers, but hundreds of millions of users. However, having many users is not for free. The servers need to … Read More »

Programming Interviews: Fizz Buzz An all-time programming classic for interviews When companies interview potential new software developers, they typically also have a programming interview to make sure that the candidate can actually write very simple programs. Fizz Buzz is a very simple classical example. The problem is easy to describe and the solution is easy as well. Problem Statement Write … Read More »