Swift is not seriously useful for server-side applications at this point. None of the web frameworks have even remotely great performance, and Swift is compatible with almost nothing on Linux, since Apple has put minimal effort into anything but macOS and iOS... so anything you do would be much more painful than using Go, Rust, or even C# (.net core) on Linux.

So, maybe you're just talking about desktop macOS in addition to phone apps?

> None of the web frameworks have even remotely great performance

Source for that claim?

Vapor has some pretty great benchmarks. https://medium.com/@codevapor/vapor-3-0-0-released-8356fa619...

It literally only compares itself to slow, interpreted languages and other, even slower Swift frameworks, with the singular exception of Go, where they're using Gin, which is a rather slow Go framework. Gin is at literally 10% of the performance of the fastest Go framework, as shown here: https://www.techempower.com/benchmarks/#section=data-r16&hw=...

So, when you cherry pick benchmarks, it can _look_ kind of fast... but then the unbiased TechEmpower benchmarks show Vapor operating at 20% of the speed of Gin. Which is 2% of the speed of the fastest Go or Rust web framework.

"50x faster to pick a different language" != "even remotely great performance."

I’m not sure this is a great benchmark (detailed in a comment above), but I think it’s undair to criticize a web framework for comparing itself to Django, node/express, Elixir/Phoenix. While dynamic languages, there’s billions of $ running on those frameworks and to present yourself as a fair alternative to those is good enough.

(I have no personal interest in Swift on the server, I use Go/echo)

i think the techempowered benchmarks [https://www.techempower.com/benchmarks/] don't show a pretty picture for swift-based web framework. But hopefully swift nio will change all that..

> We were pleasently surprised to see Vapor coming in first as being asynchronous does not really help with plaintext benchmarks. Plaintext benchmarks are really only good at testing how fast a web framework is capable of parsing and serializing HTTP headers.

I did not look if other benchmarks were released but this is probably not the best representative.

Swift on server may not have "great performance", but compared to mainstream stuff it definitely has "pretty good performance" while still providing a somewhat nice language.

I guess the key selling point is, well, being able to use Swift on the server (some people do like the language). It is pretty useful for sure. Certainly not the only choice.

That Swift is compatible with almost nothing on Linux sounds strange, not sure what you mean by that. E.g. I find it particularly nice for writing Apache modules (the Swift C integration is really neat).

P.S.: While Apple puts minimal effort in anything but macOS and iOS, others put significant effort into Swift on Linux. Like IBM.