Elastic, a company that commercializes open-source software for search and data analytics, saw its stock soar as much as 106 percent on Friday, its first day of trading on the New York Stock Exchange, under the symbol ESTC. The stock closed at $70 per share, representing a 94.4 percent rise.

The performance is more dramatic than some other initial public offerings from technology companies in 2018, including DocuSign and Dropbox.

The debut rally is all the more pronounced because it comes on a down day for the broader market, particularly the tech sector. The S&P 500 tech index fell 1.7 percent on Friday. Other companies that went public this year are getting pummeled, including Eventbrite, which is down 10 percent, and DocuSign and Zscaler, which each fell more than 4 percent.

The company ultimately raised $252 million in the IPO, selling 7 million ordinary shares of its stock. Underwriters have the option to purchase an additional 1.05 million shares within 30 days of the offering.

Elastic first filed to go public on Sept. 5. Then, on Sept. 24, the company estimated that it would price shares in the range of $26 to $29 per share. On Oct. 2, the company provided a higher estimated range: $33 to $35 per share. And on Thursday, Oct. 4, the company announced that it had priced shares at $36 per share, above the high end of the latest range.

The stock opened almost two times higher, at $70 per share. At that price, Elastic would have an implied valuation of $4.86 billion, or $4.93 billion if underwriters exercise their option to buy more shares.

"We've been talking to investors over the past two weeks and over the past two months, and the story really resonates," Elastic co-founder and CEO Shay Banon said on CNBC's "Squawk on the Street" on Friday after the stock began trading. "These investors end up talking to customers of ours, and they're very happy using our software and very proud. That effect just means that people put trust in our company."

Competitors include Alphabet's Google, Splunk, Micro Focus and cloud providers such as Amazon. Elastic provides its commercial software atop the Amazon and Google clouds. It's also available for companies to use in their own data centers.

Correction: A previous version of this story incorrectly stated that the stock was trading on the Nasdaq.

— CNBC's Ari Levy contributed to this report.