I've released 0.4.0 of https://github.com/ktdreyer/txkoji
The main change in this version is Client SSL login support.
Your Koji hub must support Client SSL authentication, and you must have a valid
SSL cert configured in /etc/koji.conf.d/*.conf
txkoji uses treq under the hood to hit Koji's /ssllogin API endpoint
asynchronously using SSL client authentication.