Can I test Clarity without the docker clarity-developer-preview image? Can I link it to my own core?
Also, will BNS become a clarity program?
You might find some information in the develop branch of blockstack-core: https://github.com/blockstack/blockstack-core/blob/develop/docs/smart-contract-vm.md
And there is also a names.clar contract for BNS in the future… https://github.com/blockstack/blockstack-core/blob/develop/sample-programs/names.clar