In R it's often mandatory to use formulas. Here I will explain the basic syntax and give some tips how to write shorter formulas.

Modoboa is a nice all-in-one email package. Sadly it lacks configuration possibilities for certificates and the default config uses just self signed certificates. This tutorial explains how to create and configure lets encrypt for your mail server.

Why not using homestead? I think it's (in some cases) a bit of overkill... Installing a virtual machine adds overhead in terms of disk space and run time.

Software Quality Assurance is a important topic - especially if you use weak typed language without static tests like php. It's a nice language for beginners, easy to learn, supports a lot of different styles and forces no specific architecture. But it's possible to provide an solid quality level. PHPUnit is a nice tool for writing unit tests, but I have shunned it far to often. Time for a change!

I had some troubles installing and using the official Appium Application under OSX so I will describe the settings and bugfixes how I got it working.

Creating basic user interface (acceptance) tests using calabash tests. The installation and configuration is focused therefore only the default gherkin sample tests are used.

In this post I explain how to write some platform independent test cases - at least I tried it ;) So I already installed Calabash on my Macbook Air and now it's time for the first test.

I had to implement a web scraping script, which fetches data from a website on a given interval. The problem was that sometimes the values were updated by the data provider and so some values in my scraping database had to be reloaded and updated as well.

Many frameworks and tools require the existence of an special environment variable directing to your java installation called JAVA_HOME. Here I will explain how to set it on linux and Mac OSX.

We wanted to speed up a php web scraper. It uses a while loop to load all data sequentially from a csv file. The performance was quite bad because the script always blocks execution while it waits for a HTTP response (this happens on each loop iteration). I used the following approach to parallelise the execution with minimal rewriting afford.

Building websites is not really rocket science. So why not automate these things? Yeah, that's easy and there are many tools or boilerplates to automate these tasks. But can we automate all (incl. designing it)? A project called the grid, tries it and last week my account was activated. Here is a short report and my first expressions.

I will show how to attack RSA, if two private keys share a same factor . This is the solution of an exercice - We had to decrypt a message given the ciphertext (encrypted message) and two public RSA keys (where a common factor was used to generate them).