I wish more software fell into this category. It's still a little odd to me that something as conceptually simple as a terminal emulator should require a full blown GPU in order to perform smoothly.
If you want to see just how fast it can be, grab a linux instance, press ctrl+f1 to drop to a GUI free terminal and see just how responsive and how fast it can run.
It's kind of nuts that we have to rely on something as powerful as hardware acceleration via GPU to make plain text rendering on a screen in a GUI approach the same speed as CPU rendered text in a straight terminal console.
Yup, I was also pretty surprised by this. I switched to Kitty recently, after terminology broke for me after an update. It's surprisingly hard to find terminal emulators that run on Xorg and on Wayland without making a fuzz.
Kitty does this beautifully and I had a real a-ha moment because of its speed the first time I tried it.
One thing is, I don't get its layout, is it possible to create a vertical/horizontal split like what (shift+)cmd+d does in iTerm 2?
Ctrl-Shift-L goes through all enabled layouts. A layout specifies how the "windows" are arranged. Simple splits are available among others. I like the stacked layout: window 1 fills the full height on the left half of the screen, all other windows are stacked on the right half.
There does not seem to be a way to control the borders within the layout with the mouse; e.g. temporarily resize window 1 in the example above to be 80% of the width. That's something I sometimes miss. It's configurable, of course, but not ad hoc.
I'm using macOS and unfortunately not familiar with how I'd do that, but I'm sure it would be easy with something like i3wm on linux (which I still miss after moving away from linux 3 years ago :/), but I don't know what I could use in macOS.
Maybe I could find some third-party solution just to show/hide a particular application. I think if I had that + if I could figure out tabbing/tiling behaviour of Kitty, I would switch to it. Those two things are the main things that I need from iterm.
How are you attributing speed to Kitty over iTerm? Wouldn't most of the sluggishness of anything be more attributed to the programs you're running in the terminal?
I prefer it to iTerm because it's so. Damn. Fast. It's the only software (besides Sublime) I run on my laptop that actually feels like it's using the 40 years of transistor improvements I'm paying for.
I know iTerm recently added a Metal renderer but I need ligature support, which iTerm Metal doesn't have.
Maintainer has also been responsive on GitHub.