Well you have sockets, and something to compute an MD5 checksum - which is actually all you need.

Forget all the generic this and that and make a simple socket client and server (homework - find out the smallest socket client and server code)

Making a client/server over a socket is virtually the first thing I do in any language when learning - very instructive

Repeat in C, TCL, JS, Java, Ruby, Python, Perl, C#

Seriously, the round trip client -> server -> client with a check that you transfer all data and loose nothing is an essential programming technique - learn to do this first THEN add JSON/XML (whatever) on top.

Once you can get two programs in different languages communicating raw bytes over a socket then you can start having fun - Use the low level socket libraries and NOT fancy frameworks - this is the slow way to program - BUT in the long term the best way - understanding is the key to programming libraries which hide what you are really doing should only be used once you understand what’s really happening

Cheers

Well a while back I wanted to transfer some files so …

What is your experience on which you base such comments?

As shown in the benchmarks by @brightball any performance hit by Phoenix for the majority of apps would generally be considered to be negligible.

If your goal is file transfers only, then it seems like Erlang should contain mechanisms to handle that already. I believe Erlang implements an sftp server (http://erlang.org/doc/man/ssh_sftp.html). I also see this article:

https://ninenines.eu/articles/ranch-ftp/

Which talks about building an ftp server on top of Ranch.

Accessing those things from Elixir to help with distributed coordination shouldn’t be too hard.

At that scale on a single server then you are looking at pure socket performance, so C/C++ or Rust with specific libraries, or Nim (I’m still heavily impressed at its significantly loaded socket performance). I’d not recommend Go or OCaml, neither perform as well as C/C++/Rust/Nim when finely tuned (though they do well when not everything is finely tuned). You will be looking at memory pools, no-alloc structures, etc… etc… Honestly just adding more servers as better as redundency is always better for such things, at which point Elixir is just fine.

Still, hundreds of thousands per second is crazy high, I’m exceptionally curious what this is. ^.^