For people not familiar, Vapor is close to releasing version 3.0, using https://github.com/apple/swift-nio. I've heard rumors that the performance is really good, but I haven't ran anything personally.
Swift itself in incredibly fast, at least in microbenchmarks. I last looked at the numbers a year or so ago, but IIRC it was about as fast as C, which is several (as in 5-6) orders of magnitude faster than, say, python.
In terms of "level of abstraction" vs "Speed", Swift is definitely at a Pareto-Optimum (if that's the term for "can't get better in one dimension without losing something in the other).
Microbenchmarks aren't the be-all yada yada yada... And it's somewhat ironic that the server framework is named Vapor. But for web apps that are computation-heavy, I think it would be a valuable option to have.
I drop in on the Vapor Slack group occasionally. I heard someone mention that version 3.0 was passing Go in benchmarks. Apparently they had some performance regressions integrating nio (it was just released last month) - not sure what the status is now.
In terms of "level of abstraction" vs "Speed", Swift is definitely at a Pareto-Optimum (if that's the term for "can't get better in one dimension without losing something in the other).
Microbenchmarks aren't the be-all yada yada yada... And it's somewhat ironic that the server framework is named Vapor. But for web apps that are computation-heavy, I think it would be a valuable option to have.