I write software for fun and for a living. For me software development is as much a passion as a source of income. Most of the software I write in my spare time and some of the software written for my clients is released as Open Source. You can find some of it on my GitHub page.
Osmium is a fast, flexible and comprehensive C++ toolkit for working with OSM data. It can, among other things, read and write OSM files in different formats, assemble way and multipolygon geometries and much more.
Based on libosmium this tool allows manipulating OSM data from the command line in many different ways. It does everything from converting file formats to filtering by tags, from creating geographical extracts to updating OSM files with the newest data.
OSMCoastline is used to extract coastline data from OpenStreetMap and bring it into an easily usable format. It is needed for most kinds of OSM maps to create land (or water) polygons. OSMCoastline is written in C++ using the Osmium framework.
OpenStreetMap uses tags to add meaning to geographic objects. Taginfo collects information about these tags from the OSM database, the OSM wiki, and other sources to help you understand what they mean and how they are used. It is written in C++ and Ruby. You can see taginfo in action at taginfo.osm.org.
Tirex is a flexible web map tile server with pluggable rendering backends and a sophisticated queue management. It is written in Perl.
I started developing Tirex in 2010, today I do not maintain it any more.
A web link checker that will tell you about broken links on your web site. It automatically keeps track of all links and only tells you about problems when they persist for several days, so that you don't get annoying emails every time a site is down temporarily. I wrote Flinch more than 10 years ago in Perl and it still does it's work for me every day.
POPular is a suite of programs for setting up large POP3 server systems. It consists of a POP3 proxy, a storage server and lots of utility programs.
POPular does not support IMAP because it was developed before IMAP became as important as it is today. I just keep it here for historical reference.