Posting source code on WordPress.com is quite simple: the platform already provides an extremely easy to use shortcode called sourcecode, based on a fairly flexible syntax highlighter plugin. By looking at the examples in the documentation page, however, it is evident that the default styling used to render sources is quite old-fashioned and does not fit most modern themes.
While the shortcode offers options to allow users to control many options of the rendering, it does not allow us to configure colors, fonts and size (the default size is so tiny that it is barely readable on high-resolution screens).
When I was writing the previous technical post, I did some investigations to figure out what options are available to post more readable sources if your blog is hosted on WordPress.com and I found out there are basically two alternatives.