What would be a terse way to (not ironically) express the notion that some thing X has gotten worse over time, and that we want to return it to a state where it is objectively the same or better than it was before?
Or maybe "Getting LLVM to compile as fast as it used to."
And 10 years ago I would have maybe suggested "Make LLVM fast again" but now it has become so strongly associated with a political party that I avoid it, precisely to avoid turning technical writings into political flamewars.
