I wasn't suggesting the case where someone explicitly does all the work and opens a PR which implements a feature of the pro version. I was moreso considering someone who had implemented something that was on the roadmap for the pro version. In either case, it's reasonable to say you would reject PRs.

I'm just wondering how governance of the project works. I assume you're already dealing with the same sort of thing with Sidekiq. I just find this sort of business model interesting since the more common approach seems to be providing hosting or priority support.

Yep, It's my job to communicate a vision for the product: what types of features are Pro, which are OSS. Right now my rule of thumb is "team" or collaboration features are Pro, the rest is OSS. Yes, I would close PRs if they provide more enterprise-focused features that I wanted to sell but not before chatting with the submitter and seeing if there was a common ground or some feature subset which could be open sourced.