The world's smallest webserver

Run this from the command line:

ruby -rsocket -e's=TCPServer.new(5**5);loop{\
_=s.accept;_<<"HTTP/1.0 200 OK\r\n\r\n#{\
File.read(_.gets.split[1])rescue nil}";_.close}'

Then, to get the message of the day, point your browser to http://localhost:3125/etc/motd, which prints on my system:

DragonFly v6.5.0.1202.gd5712-DEVELOPMENT (X86_64_GENERIC) #23: Mon Dec 22 21:54:04 CET 2025

Welcome to DragonFly!