Some time back in April 2013 I was bored and looking for a new project to keep my attention, if only for a short period of time.

My colleague @codeinthehole had an idea but no time to implement it, this idea was to have shields like those of travis-ci (shown below) but displaying package download counts.

Status of blackhole on Travis CI

Tech stack

From the very start I decided to use Tornado framework, although this may change in the future.

The original plan was to generate the images using Pillow (PIL) and then simply cache them to disk. I decided it would make far more sense to do this using Varnish and not have to worry about it working as expected.

Manually generating the images

The images were originally generated from a base template using Pillow, but sadly Python’s image manipulation is not very good, especially it’s text manipulation and the shields could …