Microsoft stock has risen 20% since Satya Nadella took over from ex-CEO Steve Ballmer back in February, but despite this, it seems that Nadella has a lot more on his agenda of reshaping Microsoft. This week Nadella made headlines for announcing 18,000 layoffs, which is the biggest layoff in the company’s history.

Nadella is now going through the second phase of reshaping Microsoft since he became CEO. His first phase was essentially tearing down what Steve Ballmer left behind. Now he has to rebuild it according to his vision of what the company should look like. It’s during this phase that he will be under the microscope, and will have to prove his worth as the new leader of the tech giant.

Nadella has made a number of important decisions during his short tenure at Microsoft. He reportedly ditched the Surface Mini at the last minute, and a lot of the momentum related to cloud computing has been under his direction.

Despite this, a lot of what Microsoft has released since February was already underway under Ballmer’s direction, which is largely why, from now on, Nadella will be scrutinized for his decisions.

With Microsoft having absorbed Nokia’s phone business, many expected the layoffs to largely be of ex-Nokia employees. While many of the layoffs were of those employees, 5,500 other employees were laid off, making huge changes to the Windows team and testing team.

The future of the tech giant now seems to be a little unclear, despite Nadella having described what actions he will be taking to integrate what is left of the Nokia business.