Kickstarter CEO Perry Chen issued an open letter on the site’s blog today, noting that he will be stepping down from his role. The executive served as one of three co-founders for the service, launching the site in 2009, with Yancey Strickler and Charles Adler. He served as CEO for Kickstarter’s first five years and returned to the role two years back.

He notes in his post that he will stay with the service as chairman of the board, focusing “on high-level and long-term company needs.” Kickstarter will be promoting its head of Design and Product, Aziz Hasan, as interim CEO, as Chen steps away from day to day operations.

“When I returned as CEO in 2017, I initially intended to spend about six months working to set up a long-term foundation to ensure Kickstarter remained aligned with its mission, and to set the next leader up for success,” Chen writes. “Those months quickly became two years dedicated to developing a better way to deliver on the core aspects of our service through a robust operating system, a strong product, and the team we have assembled at Kickstarter today.”

It’s been an impressive run, certainly. Chen himself notes that the service has seen $4.2 billion pledged to projects and around 160,000 projects getting successfully funded. Next month, Kickstarter will celebrate its 10th birthday.

This key change in management also comes as the company’s staff announced plans to unionize. Kickstarter employees are teaming with the Office and Professional Employees International Union (OPEIU) Local 153.

The staff notes in a statement: