npm i reverse-dns-lookup

npm start

curl -H 'Content-Type: application/json' -d '{"ips":["8.8.8.8", "8.8.4.4"]}' http://localhost:8465/

# Example formatted output:
# {
#    "8.8.8.8" : [
#       "google-public-dns-a.google.com"
#    ],
#    "8.8.4.4" : [
#       "google-public-dns-b.google.com"
#    ]
# }