[prattmic]

I’m not familiar with Upsource, but what you describe sounds somewhat like the Gerrit review process. Each commit is reviewed individually, but sending multiple dependent commits for review is supported as well. It is technically possible for a coworker to build on top of your unsubmitted changes (by checking out your commits and adding more on top). However this process gets somewhat painful if the coworker updates their commits, which would require you to do a convoluted rebase.

[mdaniel]

I played with Upsource back when it was their "static-analysis in the cloud," and it actually was cool, but holy hell it was a beast to get up and running, and (just like Qodana that they're trying now) the static analysis was(is?) indescribably hard to configure correctly to get meaningful results

I've heard great things about Gerrit, but it also seems like one of those "strongly opinionated, mailing-list based" review systems, and trying to lobby for such a thing in the GitHub/GitLab web based world is practically a non-starter in my experience

[prattmic]

Gerrit is pretty strongly opinionated, but it is not mailing-list based. Review notifications are sent via email, but otherwise everything needs to be done via the web UI (or other tool using the API).