[xmodem]

> likely perform far better at serving static content and other cacheable requests.

But at the cost of having a separate build step that deploys your static assets somewhere. Jetty is actually pretty fast - I've built some fairly high-volume internal apps this way.

> Also allows you to run two binaries at once for a rolling update.

You don't necessarily need an extra reverse proxy layer for this, though I will concede in some environments it's probably the easiest way to achieve it.

[zeroCalories]

You don't necessarily need to deploy your static content anywhere, you can just set nginx to cache your content.

Also, most other rolling update solutions will end up being more complex than having a reverse proxy. What do you have in mind that would be simpler? NixOS?