Linux, X11. Using eb231b3, release build (the AUR one).

Starting up alacritty takes a significant amount of time. Simply doing time alacritty -e false reports about 390ms. Other terminal emulators, such as urxvt or termite start much faster, at about 160ms for both.
It's also not just a matter of this simple benchmark, in normal usage it also feels slower to start.