Nikil Viswanathan NBC Video screenshot Airline fees have become something of a universal certainty — along with death and taxes.

That is why when a 25-year-old Stanford grad coded a simple website to check him in automatically 24 hours before a flight, Southwest Airlines sent him a cease-and-desist letter threatening to sue him, according to NBC.

He took it down immediately, although he says he disagrees with Southwest.

What the airline claims Nikil Viswanathan did was create a website that competed with its own $10 "Early Bird" check-in option, which allows passengers to choose seats before everyone else.

Viswanathan wrote up the code in less than an hour back in January, and at the beginning of October, he created the CheckIntoMyFlight.com domain for it.

That is when it exploded — by the first week of the month, the site had 5,000 visits, Viswanathan writes on the now defunct website.

Following his short, but much publicized conflict with Southwest, the coder received and turned down job offers from Expedia and Facebook.

“My favorite question is, ‘What would you do if you had unlimited time, unlimited money?’ And it’s like, exactly what I’m doing right now," he told NBC.

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