Joachim Breitner


This project list is far from complete. Unfortunately, I did not yet find the time to fix this. You can find more on my weblog, on GitHub and Open HUB.

The Incredible Proof Machine

The Incredible Proof Machine is a tool to perform proofs in various logics (e.g. propositional, predicate logic) visually: You simply add blocks that represent the various proofs steps, connect them properly, and if the conclusion turns green, then you have created a complete proof!


The Ravensburger Tiptoi® pen is programmed via special files. Their file format has been reverse engineered; this is a tool to analyse and create such files.


The Automatic Rule-Based Time Tracker is a desktop daemon that runs in the background and, every minute, records what windows are open on your desktop, what their titles are, which one is active. The accompanied statistics program lets you derive information from this log file, i.e. what how much of your time have you been spending with e-Mail, or what projects are your largest time wasters. The mapping from the raw window titles to sensible „tags“ is done by a configuration file with an powerful syntax. See the documentation for more detailed information.


Gipeda is a a tool that presents data from your program’s benchmark suite (or any other source), with nice tables and shiny graphs. Have a look at the Demo page and the GHC’s gipeda installation.


If you just want to disply a word or a short, possilby multi-line, text as large and as quickly as possible on your screen, then “screen-message” is the right too for you. It has been used already twice at a Debian conference for the Mugshots. “screen-message” runs on Linux and Windows and there is an online version on


The unicode-screensaver is a simple screensaver application that repeatedly randomly picks an unicode character and displays it in a very large font size together with its unicode code point and the character name.


libnss-gw-name is a Name Service Switch (NSS) module that resolves the name “gateway.localhost” to the IP of the current default gateways of the system. This allows easy access to router configuration and to check if connectivity problems are local or not.


This gtk module allows you to take a screenshot of a running gtk-3 application as a vector image, with fully scalable graphics and selectable text. It supports rendering the application to PDF, SVG and PostScript.


My Thinkpad laptop has a small light in the frame, originally ment to enlighten the keyboard in dark environments. I use it to indicate new pidgin messages. New versions are uploaded directly to the debian archive, users of other distributions can get them there.


You can find a wiki software that allows to edit LaTeX documents collaboratively on It is currently in use to write down lecture notes for various lectures, such as Analysis I,II and III as well as Info-II and Stochastic I. This takes place on Before November 2006 both ran, based on KWiki, on the site


For linux computer who run as a router between two networks and have to forward udp broadcast messages, for example for games, is this small program.

Old projects

These projects are not really useful, or were never finished. They are listed here for nostalgic reasons.


I wrote a small program for windows, in Delphi, that diesplays the currently played song on the German radio station “SWR3”. It only works if the corresponding “server” on my machine runs. You can download it here.