• flask ( backend )
• js/css/html ( frontend )
• socket ( for whois queries )
• ssl ( wraps socket )
• tldextract ( extracts tld from dname )
• cachetools ( caches requests )

When a domain name is requested, it is passed to the whois.query.Whois( 'example.com' ).request() module, the module extracts a tld from the domain name via tldextract to query whois.iana.org to find the whois server responsible for the domain zone. The query then goes to the responsible server to get information about the domain name. Connection to the servers is on port 43 https://datatracker.ietf.org/doc/html/rfc3912#section-2.