Let’s Encrypt is a free certificate authority run as a non-profit organisation. I decided to try setting it up on my server, and was finished within five minutes. The certbot tool has been packaged for Debian and has been backported for Jessie. A single command configured Apache to redirect to https always, create the SSL cert, install it and create a systemd timer file to automatically renew it:
Debian is my Linux distro of choice. I first started using it sometime around 2003, but switched to Ubuntu for several years because I became frustrated with the age of the packages in it’s repository. Going back to Debian has made me appreciate it much more than I did before, several years of fixed versions with security updates means that I can write software and mostly forget about it until the next release.
The Decimal class in the standard library is the way to avoid double precision errors in Python.