private def start_server(port)
      ws_handler = ->( ws : HTTP::Websocket, ctx : HTTP::Server::Context ) do
        loop do
          select
            when msg = chan.receive then ws.send msg
            when timeout 1.second then nil
          end
        end
      end

      server = HTTP::Server.new([
        HTTP::ErrorHandler.new,
        HTTP::LogHandler.new,
        HTTP::CompressHandler.new,
        HTTP::WebocketHandler.new(ws_handler),
        HTTP::StaticFileHandler.new("./output/", directory_listing: false),
      ]) do |context|
        if is_html_index_request?(context)
          context.response.status_code = 301
          context.response.headers["Location"] = "#{context.request.path}index.html"
          puts "\nRedirecting implicit HTML index request..." # TODO colorize
        else
          context.response.status_code = 404
          STDERR.puts "\nFile not found!" # TODO colorize
        end
      end

      address = server.bind_tcp port
      puts "Listening on http://#{address}"
      server.listen
    end