CI/CD free for hobby side projects. Jenkins on Heroku as alternative, with ephemeral dyno I have four side projects which are my hobby (NOT A JOB! NOT A WORK!).

I work on that at night, when I have time and when I want to.

All projects are javascript backend and frontend. Just experiments.

What I need is a Jenkins instance (or something like that for CI (continuous integration) and maybe also CD (continuous delivery)) but free. Maybe like free heroku dyno which is amazing: I don't work everyday on it, I work sometimes, when I have time and, like my free dyno on Heroku it's amazing the auto-sleep and go on just when I need it.

Is there something for Jenkins out there but free, with auto-sleep?

Jenkins on Heroku is still an option given the ephemeral state of dyno on Heroku? Is Jenkins still saving config on filesystem?

I can't afford to pay something for that because it's just an experiment.

Any idea?
You should try CI / CD like:


Codeship ( free tier, and totally free for open source projects )
travisci
circleci, ...


Openshift, as @JamesKnott mention, but this one is a full PaaS, so it is meant to host your app too. 

Hope it helps