Kemal

Lightning Fast, Super Simple web framework for Crystal. Inspired by Sinatra but with superior performance and built-in WebSocket support.

Super Simple ⚡️

require "kemal"

# Matches GET "http://host:port/"
get "/" do
  "Hello World!"
end

# Creates a WebSocket handler.
# Matches "ws://host:port/socket"
ws "/socket" do |socket|
  socket.send "Hello from Kemal!"
end

Kemal.run

Start your application!

crystal src/kemal_sample.cr

Go to http://localhost:3000

Check documentation or samples for more.

Super Fast 🚀

Numbers speak louder than words.

Framework	Request Per Second	Avg. Response Time
Kemal (Production)	100238	395.44μs
Sinatra (Thin)	2274	43.82ms

These results were achieved with wrk on a Macbook Pro Late 2013. (2Ghz i7 8GB Ram OS X Yosemite)

Features

• Support all REST verbs
• Websocket support
• Request/Response context, easy parameter handling
• Middlewares
• Built-in JSON support
• Built-in static file serving
• Built-in view templating via Kilt

Documentation

You can read the documentation at the official site kemalcr.com

Thanks

Thanks to Manas for their awesome work on Frank.