The website’s rules of operation repeatedly note that the service does not condone illegal activity, but that appears to have done little to stop people from seeking to hire hackers to carry out tasks that most would say break the law.

But Mr. Tendell said much of the criticism of Hacker’s List was misplaced. He noted that even if an illegal job were posted by an anonymous user, it would not necessarily be carried out. He said clearly illegal job postings were removed if someone complained, but he said what mattered were the jobs that were completed.

“No one is going to complete an illegal project through my website,” he said.

Still, Hacker’s List has had its share of operational hiccups since its debut, and its website has crashed a number of times. A few more than 4,000 potential jobs have been posted on Hacker’s List, but many of them have not received a bid from a hacker. Mr. Tendell said about 250 jobs had been completed since the website went online.

Some hackers have tried to disrupt the service, and more recently the service has banned hackers who were looking to defraud job posters.

A few days ago, Twitter suspended the Hacker’s List account, which automatically sends out new job postings. Twitter would not comment on the suspension but many of the account’s tweets promoted jobs like “hack a PayPal account.” Mr. Tendell said he did not know why Twitter suspended the account. (On Tuesday evening, Twitter lifted its suspension of Hacker’s List account, @hackerslist. A Twitter spokesman declined to comment.)

Mr. Tendell’s role in setting up Hacker’s List was unmasked in part by Erik Solomonson, a blogger who lives in New York and works for a web hosting company. He decided to do a bit of digging into the formation of Hacker’s List. Mr. Solomonson unearthed an archived domain registration statement for Hacker’s List from October, just before the website went live, that listed Mr. Tendell as the administrator and contact person for the site.

A few weeks later, Mr. Tendell’s name was removed from a revised domain registration. The name that replaced his was David Harper, who is said to live in New Zealand and could not be contacted.