With Impossibility, you just need to input a keyword and it combines it with a carefully selected list of nouns, verbs, and adjectives. Then it searches the results for unregistered .com domain names. You can choose 4, 5, or 6 letter word domains with your keyword. There is also an “anything” option which will generate a much broader list of domains. If you are not sure if you like the list of domains you can just “Get more” and it will generate more domains.
Checking hundreds of domains for availability takes a while, so Impossibility uses multiple servers in parallel to speed things up. Currently, it has six domain lookup servers spread across five different datacenters. Impossibility is written primarily in Node.JS, with a bit of PHP used for domain availability checking. Node acts as the primary webserver, domain generator, and also handles load balancing across our pool of lookup servers. It uses servers from iPage and Linode.