I have googled without any interesting results. I'm looking for an open course membership application. Does anyone know of such a thing?

Does Pixl8 have an open source version of their membership app, @alexpixl8?

We produce https://readymembership.com but its not open source or free

Is ReadyMembership an SaaS type thing or a software package we install on our servers?

It’s more SaaS+ each of our clients gets deployed on a different container within our kubernetes cluster. We do have the ability to extend and customise per deployment, it’s a coldbox app.

Is ReadyMembership built using PresdieCMS?

yes