Recent Posts

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 »

6 Alternatives to Classes in Python Speed of development, execution time, (de)serialization, and maintainability all play a role in making your code shine Photo by the author. As developers, we throw a lot of data around. The representation of data matters a lot and we need to be able to keep track of which variables represent which attributes. Configuration is a prime example of complex data. In the following article, I will use … Read More »

Shift Left: 7 Stages to Speed up Application Development while Improving Quality Let’s do it in an agile way Image by Martin Thoma The quicker you spot mistakes, the easier it is to fix them. This is the whole idea of “shift left”. When you are getting a call from your boss or the support team that “it doesn’t work”, you know that this will take a while … Read More »

The UTXO model A technical cornerstone of Bitcoin Visualization of a transaction. Image by Satoshi Nakamoto (Bitcoin: A Peer-to-Peer Electronic Cash System) Bitcoin is based on the UTXO (unspent transaction output) model to ensure that nobody is able to spend money they don’t have and prevent money from being spent twice — so-called double-spending. In this article, you … Read More »

Docker Security 😇 A hands-on guide to security for Docker Photo by Andrey Sharpilo on Unsplash Most companies I have seen deploy Docker images in at least one project or service. Docker is great because it makes stuff reproducible by specifying the environment to a big degree. However, you still have to think about security. Let’s have a closer … Read More »

Encryption vs Encoding vs Hashing They might appear in the same context, but they are vastly different Encryption is about keeping a secret and being able to restore it. Hashing is about fingerprinting — you don’t need to restore the original, but you need to make sure it is identical. Encoding is about data representation to enable information exchange. Encoding does not involve keeping secrets. This was … Read More »