Haskell for webservice? Real-Time!

RT graph about webservice written using Haskell

Yesterday, a friend started a war about a programming language for Real-Time API. He did a little mistake because I’m always… I remember the very long war about Emacs vs Vim (Vim wins).

The subject was about RT (Real-Time) web service/microservice.

What’s RT?

We consider RT a latency less than or equal to 30ms.

I let you imagine 2 microservices:

  1. service 1 sent a request to service 2
  2. service 2 received the request from service 1: process and send the reply
  3. service 1 received the reply from service 2

The time between point 1 and point 3 ≤ 30ms

Tools used for this quick RT webservice

To test and obtain the graph, I used rtapi (from Nginx)

Nothing more… KISS > all

Code and online test

  • code: https://github.com/sycured/streaming-calc-haskell-yesod
  • container ready to use: ghcr.io/sycured/schy:latest
  • test server: https://schy.sycured.com

Will I use Haskell for a real-world app?

I love Haskell because we don’t have side effects.

Performance + no side effect = 💓

Read more about NodeJS vs Haskell

  • https://gist.github.com/paf31/9c4d402d400d61a49656
  • https://www.fpcomplete.com/blog/2016/12/concurrency-and-node