Thanks! That's hugely helpful - everything I could find myself seemed to be an order of magnitude or so slower than that (and they support ecdsa, too, so I can'

Thanks! That's hugely helpful - everything I could find myself seemed to be an order of magnitude or so slower than that (and they support ecdsa, too, so I can't even object on the basis of algorithmic support). With hindsight my reply was somewhat flippant - really I just wanted to push back on the idea that this was a problem that could be solved by simply sprinkling HSMs on it rather than something that requires a meaningful infastructural effort. Github is a sufficiently core piece of infrastructure that I agree more should be expected, and I hope this does serve as encouragement for them to do that.