Shares of nuclear reactor developer X-Energy jumped in its trading debut Friday, rising 27% to $29.20 after going live on the Nasdaq shortly before 1 p.m.

X-Energy raised a little more than $1 billion in its initial public offering late Thursday, a larger-than-expected sum that put its market cap around $9 billion.

What sets X-Energy apart from other early-stage nuclear players is its commercial relationships, which include power deals with Amazon, Dow, and U.K. energy firm Centrica. Amazon is also an equity investor.

Those relationships may be why the Maryland-based nuclear developer got such a rousing response from Wall Street. It was aiming to sell about $700 million worth of shares at a per-share price of $16 to $19. Instead, the stock priced at $23.

“I think they were impressed with the validation that we’ve received from our tier one customers,” CEO J. Clay Sell told Barron’s on Friday. “We’ve got great partners with big balance sheets.”

Competitors Oklo and NuScale both fell on Friday.

Sell said he expects the company to receive licensing this year for its first reactor, which will be built for Dow in Texas. He thinks it will be up and running by the early 2030s. After that, the company will be building reactors for Amazon in Washington state.