NodeMCU based PIR motion sensor supporting WiFi and MQTT
7 mins
Mini tutorial on how to use the NodeMCU Amica and a cheap PIR sensor module to build a pretty simple motion sensor that supports reporting via MQTT messages.
Frama-C predicates
4 mins
Really short primer on ACSL predicates for formal verification of ANSI C code with Frama-C.
Frama-C with wp-dynamic and function pointers
9 mins
How to use Frama-C static analysis and proof assitant with ACSL annotations for function pointers in ANSI C.
How this site is built with Jekyll and Jenkins
5 mins
A short summary on how this page is built using the Jekyll static website generator as well as a really simple Jenkins job that's triggered by a GitHub webhook.
Automatic Ethernet and WiFi failover on FreeBSD
3 mins
Short introduction on how to use lagg(4) to perform automatic seamless switching from ethernet to WiFi (when they represent the same network on the same IP subnet) and back on FreeBSD.
Simple usage of Kerberos for SSH authentication on FreeBSD
9 mins
A short primer on how to get started using Kerberos for authentication inside your network. This includes setup of an kerberos key distribution center (KDC) on an secure host as well as of the server machines against which one will authenticate as well as the required configuration on the clients.
Selenium with Chromium and Java on FreeBSD
9 mins
This is a short description on how to get started using Selenium with chromedriver on FreeBSD with a Java application. This can be used to develop automatic test applications for web applications or simple bots that scrape content from webpages or automate actions on the web using a full browser capable of running JavaScript, running browser plugins, etc. (Update - In addition an implementation in Python has been added to show a short draft on how one can get started with Selenium in Python as well.)
AWS first steps - How to initialize the admin IAM user and initialize CLI tools
4 mins
Real first mini steps when using Amazon webservices. Adding 2FA to your root user, creating an administrative user, enabling 2FA there and creating access keys for CLI tools.
