Thank you, and to others as well who have mentioned --incremental! I can't believe I never thought to look at the documentation for `jekyll serve`. This will make my life much easier.
Another note on using Hugo. I have really enjoyed working with Hugo, both for the speed and for the overall experience. I ran into an issue where the table of contents was not rendering properly. I believe it's a known bug, perhaps just with some themes. Since I'm not familiar with Go yet, I came up with a quick fix by writing a quick Python script that converts all the incorrect TOC links to the correct links for my site. It's plenty fast for me, and I can always make it faster by using bash or sed, or learning a little Go and patching Hugo. At some point I'd like to do that just to contribute back to the project. So it's quite possible to use a static site generator in a language you're less familiar with, and create quick tooling scripts around it for any issues you run into that you don't want to deal with in the generator's native language.
Another note on using Hugo. I have really enjoyed working with Hugo, both for the speed and for the overall experience. I ran into an issue where the table of contents was not rendering properly. I believe it's a known bug, perhaps just with some themes. Since I'm not familiar with Go yet, I came up with a quick fix by writing a quick Python script that converts all the incorrect TOC links to the correct links for my site. It's plenty fast for me, and I can always make it faster by using bash or sed, or learning a little Go and patching Hugo. At some point I'd like to do that just to contribute back to the project. So it's quite possible to use a static site generator in a language you're less familiar with, and create quick tooling scripts around it for any issues you run into that you don't want to deal with in the generator's native language.