# MongoMatch query used for each browser key
	#
	# Because parsing user agent string is a pain in the nit, we go lazy on this
	# one. We associate each broswer key like `Chromium` to the query that allows
	# us to count the number of visits.
	var browser_queries: HashMap[String, MongoMatch] do
		var map = new HashMap[String, MongoMatch]
		map["Chromium"] = (new MongoMatch).regex("user_agent", "Chromium")
		map["Edge"] = (new MongoMatch).regex("user_agent", "Edge")
		map["Firefox"] = (new MongoMatch).regex("user_agent", "Firefox")
		map["IE"] = (new MongoMatch).regex("user_agent", "(MSIE)|(Trident)")
		map["Netscape"] = (new MongoMatch).regex("user_agent", "Netscape")
		map["Opera"] = (new MongoMatch).regex("user_agent", "Opera")
		map["Safari"] = (new MongoMatch).land(null, [
				(new MongoMatch).regex("user_agent", "Safari"),
				(new MongoMatch).regex("user_agent", "^((?!Chrome).)*$")])
		map["Chrome"] = (new MongoMatch).land(null, [
				(new MongoMatch).regex("user_agent", "Chrome"),
				(new MongoMatch).regex("user_agent", "^((?!Edge).)*$")])

		return map
	end