Alacrity is intended to be used with a multiplexer like tmux, at least for now. I doubt you'll see tab support any time soon, if ever.
Maybe if electron's dependencies could be compiled down to the minimum functionality needed by a given application this could work.
It means rendering without the UI from what I understand.
once you add in e.g. tmux for multiplexing and scrollback, then you are bottlenecked at tmux's speeds, as opposed to the terminal emulator's speeds (not like it really matters, but its an interesting effect)
Where will the bottleneck be?
https://www.reddit.com/r/programming/comments/5mflek/alacrit... The Terminology (another light-weight term, with memory goals, that has scrollback) developer's comments are here