[comice]

It matters to me as a personal user because my use of duplicacy might change at some point and suddenly I'd lose rights to use it (unless I pay). I'd lose rights to any development contributions I might have made unless I pay.

And as a personal user, I can't use any code from Duplicacy in any other project. I can't even, say, create a package for it and get it included in Debian.

And aside from some of these practical issues, I'm a personal user who supports software freedom so I don't want to use something encumbered in this way.

And as a commercial user, any development contributions I make are no longer my own and I have to pay to make use of them.

But the worst part of it is, your license isn't very well defined. As it stands, you may at any point stop accepting license payments from a commercial user and they'd lose the right to use it entirely - they'd lose access to their backups (unless they used the software without a license).

You of course have the right to choose any license you like! I just wouldn't use duplicacy myself under the terms of that license.

[acrosync]

Thanks for your feedback. The reason I don't like open-source licenses is that I don't want for-profit companies to use my software without paying. The ideal license would be the one that requires them to pay while being appealing to personal users like you. I don't think these two goals are irreconcilable, but unfortunately such a license doesn't exist yet.

[comice]

I did wonder if being fully free might encourage more users who might fund you in other ways but Borg backup isn't making very much like that, so perhaps not: https://www.bountysource.com/teams/borgbackup

The AGPL license might be a step in the right direction (for your requirements). It aims to at least ensure that if companies use the code to provide a service to other users, they have to release their changes. You can sell those companies a different license if they don't want to accept the AGPL (you'd have to have a contributor agreement to assign copyright to you though, to allow you to relicense code at your discretion like that).

Or there is the open core model (like nginx-plus), where you provide the code under an open source license but provide some additional "enterprise" features (like your vmware stuff) to only those that pay. I'm not a fan but it seems to work for some.

Anyway, duplicacy sounds a great design. All the best with it!