Yeah, per second billing is nice. I can see this working where you want to change/test lots of containers briefly.

The only type of service which seems comparable is Joyent and hyper seems to be a bit cheaper.

https://www.joyent.com/pricing

Hi, there are plugins for Buildbot and Jenkins github.com/jenkinsci/hyper-slaves-plugin, which are more like a "Serverless" CI/CD solution.

PS: I'm the founder :)