If you thought Amazon was adding its Alexa voice assistant to too much stuff, you probably haven’t seen anything yet.

As part of Amazon’s fourth-quarter earnings report Thursday, founder and CEO Jeff Bezos said there will be “much more to come” from Alexa development.

“Our 2017 projections for Alexa were very optimistic, and we far exceeded them. We don’t see positive surprises of this magnitude very often — expect us to double down,” Bezos said in a statement. “We’ve reached an important point where other companies and developers are accelerating adoption of Alexa.”

Bezos’ plans to expand Alexa are just one part of the company’s aggressive push to get bigger. In the past few weeks alone, the company opened a tropical forest/office space in the heart of Seattle, moved into the next stage of its lottery to find a new headquarters, and even shook the health care industry with a new company aimed at improving its employees’ health.

All this work shows that Amazon will someday stop growing so quickly, but that day hasn’t arrived just yet. Amazon’s fourth quarter results, its biggest period of the year thanks to holiday sales, highlight that fact.

Amazon posted revenue of $60.5 billion, up 38 percent, from a year ago. Meanwhile, earnings surged $1.9 billion, or $3.75 a share, up from $749 million. The latest quarter included a $789 million benefit stemming from changes related to the new U.S. Tax Cuts and Jobs Act. Analysts expected $1.85 per share in profit and $59.8 billion in revenue, according to Yahoo Finance.

Among Amazon’s most recent efforts, Bezos earlier this week unveiled a new corporate office space/indoor tropical forest in Seattle called the Spheres, which represent both the company’s rapid growth and growing influence in its hometown.

Not settling for being stationed in just one major city, Amazon is also embarking on a public dating game with 20 other North American cities to find a suitable location for its second headquarters, dubbed HQ2. That project is expected to cost over $5 billion and eventually include 50,000 new hires, but is already generating a bidding war among municipalities to land the company.

On top of that, Amazon this week announced it’s teaming up with JPMorgan Chase and Warren Buffett’s Berkshire Hathaway to create a new company to try clamping down all three organizations’ employee health care costs. Details on the initiative are thin, but the plan already beat up health care stocks. Oh, and Amazon also opened its first ever store that does away with cashiers, called Amazon Go.

But will spending on all these projects pay off for Amazon, its employees and investors?

“What is obvious is that Amazon is investing heavily for future growth,” said Moody’s analyst Charlie O’Shea. “What is far from obvious is where these investments are being made, how much these investments are costing, and when returns will begin to be generated.”

Wall Street so far has ignored many of these questions, instead bidding up Amazon’s stock to new highs.

Shares are up 2.9 percent after hours to $1,430.