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I’m an independent IT consultant and entrepreneur in the Internet and software business. I’m interested in design, enterprise applications, web apps and SaaS products. I design and develop business solutions and applications. I help companies in terms of software quality and knowledge transfer, e.g. with Angular and Spring Boot.

Big O Notation Explained

Conrad Reeves recently published an article on Big O notation on That Computer Scientist, in which he tries to explain this - seemingly daunting - subject as easily as possible. Big O notation is a method for ranking an algorithm's efficiency in terms of time (e.g. CPU cycles) or space (i.e. storage or memory) requirements. In a nutshell, Big O notation allows you to make rough approximations like for example: "In a best case scenario the algorithm in question at most will ... Read more

Two Hard Things in Computer Science

I've always liked Jeff Atwood's variation on Phil Karlton's original quote "There are only two hard things in Computer Science: cache invalidation and naming things.": There are two hard things in computer science: cache invalidation, naming things, and off-by-one errors. However, with reactive programming these days this version by Dave Stagner probably is even more appropriate (especially since it uses zero-based numbering, which of course is the only decent way of indexing elements in a sequence ...): 0) Cache invalidation 1) Naming things 5) Asynchronous callbacks 2) ... Read more

Admiral Grace Hopper Explains the Nanosecond

Grace Hopper was a brilliant computer scientist, who - among numerous other achievements throughout her career in mathematics and computer science, the military, and the at the time nascent software business - can be credited with having had a pivotal role in the development of the business programming language COBOL (which quite deservedly got her the nickname Grandma COBOL and which in turn gave rise to enterprise software and the enterprise software industry) This is her visually explaining what a nanosecond ... Read more

Big O Notation: Less Scary Than You Might Think

As a software developer chances are that at some time in your professional life you'll come across a mathematical concept called Big O notation. Now, if you happen to not have a traditional university computer science / maths background, you might have a bit of a hard time grasping the common - usually strictly mathematical - explanations of Big O notation. Big O notation is tremendously useful for reasoning about performance and memory consumption of algorithms. Depending on the exact nature of ... Read more