Take a look at Reaction Commerce[0]. They are pitching themselves as an open-source Shopify competitor which you can host on your servers.
Is Meteor still being actively developed?
https://github.com/meteor/meteor
looks like they're a monorepo now:
https://github.com/meteor/meteor/tree/devel/packages
but its slow going, from the looks of it perhaps.
I think the meteor community is a shell of what it used to be, though.
I wonder how Smile Software is handling it, they were 'all in' on meteor when they announced their subscription pricing model.