Puppet masterless project setup guide

December 8, 2018

This document is a proposal for a Puppet project setup. It covers the setup of masterless Puppet module and provides a layout for a proper project structure. It will give you an example for a nginx module that can be deployed locally and remote. Further the roles and profiles concept will be applied and coupled with the hiera configuration data.


Find certificate files that will expire soon and create a csr

November 29, 2018

The certificate expiration period should be kept as short as possible in a public key infrastructure. But the cost of resigning certificates must not be too high. This trade off causes a lot of problems. Every now and then a certificate expires without anybody noticing it or the same certificate is used for 10 years, which is obviously a security risk. In order to avoid this problem you either use Let’s Encrypt or another fully automated certificate management system. If this is not available you must know at least which certificates are going to expire soon.


State of JavaScript 2018

November 19, 2018

State of JavaScript 2018 has just been released. It is one of the biggest survey about JavaScript development. If you wanna know what is going on in the confusing world of JS, make sure to pay a visit. They did a great job at visualizing and showcasing the results.


Raspberry Pi thermometer that connects from anywhere via broadband

November 16, 2018

This tutorial is about how to build an online accessible thermometer using the Raspberry Pi 3 B-model.

We will start by buying the electronic components and finish with a chart showing the temperature data.

Walking through the tutorial requires basic knowledge in working with linux and advanced knowledge in building web applications. Whereas the web application part is optionally.

Using a mobile broadband connection and a thermo sensor our Raspberry Pi will measure the temparature and save it to a graphql server.

Using react and a graphql client library we will create a chart with the temperature data.


FDA for Algorithms and Technology

November 14, 2018

I form my opinions and judgments not based on newspapers and talks with people, but mostly from listening to podcasts and reading hacker news. An idea that showed up in my feed a lot recently, is establishing an Food and Drug Administration (FDA) for algorithms1 and technologies2.

Algorithms and technologies haven changed the very fabric of human interaction and communication. The economic landscape has shifted, the service sector took over the largest part of the pi and tech companies lead the top. Online platforms run by powerful algorithms and technologies have become the interchange for consumers and suppliers. Social networks turned into basic building block for socializing.


Setup GoCD environment using docker

November 6, 2018

At AdNovum we are running GoCD for automating the continuous delivery (CD) of our software products. GoCD has become the de facto standard for running CD pipelines.

In this post I will give you a short introduction into GoCD using docker. We are going to setup a GoCD environment consisting of a server, an agent and deployable material. Further we are going to configure a deployment pipeline and build an node.js application.


O3M 79 - Summer

October 26, 2018

The summer is gone, but this playlist stays.


Magnificient India

October 24, 2018

I backpacked the north of India for three weeks. These are the impressions and memories I got from this amazing trip.

This was the most shocking part when I arrived in India. There is trash everywhere and obviously no system nor institution that cares about collecting and recycling trash.

Garbage everywhere

This was the most shocking part when I arrived in India. There is trash everywhere and obviously no system nor institution that cares about collecting and recycling trash.


System Observability and Chaos Engineering

September 16, 2018

At the last Jazoon tech days I learned about the current state of DevOps and other related topics. During the talks “chaos engineering” and “observability” were mentioned many times. I didn’t know either and became curious what it was about.


Undo a pushed git merge

September 11, 2018

First of all the solution to the problem I am tackling should not exist in the first place. If you have to revert a merge on a git branch, think about alternatives. If not other option is left, I’ll show you how you can undo a merge with git revert.