Mozilla announced Thursday afternoon that Andreas Gal, an engineer who helped launch the Firefox operating system and currently serves as Mozilla’s vice president of mobile, is the company’s new chief technology officer.

“My new responsibilities at Mozilla include identifying and enabling new technology ideas from across the project, leading technical decision making, and speaking for Mozilla’s vision of the web,” Gal wrote on his personal blog.

Gal replaces Brendan Eich, a Mozilla co-founder who was promoted from CTO to CEO in March only to resign 11 days later due to a controversy stemming from his donation to an anti-gay marriage bill in California.

“Andreas is widely recognized as an authority on web technology and as a strong technical leader,” Chris Beard, the interim CEO of Mozilla, wrote on Mozilla’s official blog.

Gal’s Ph.D studies on accelerating the JavaScript programming language, which Eich invented, brought him to Mozilla six years ago. Beard said he played a “key role” in Mozilla’s key tech initiatives.

Gal will focus on expanding Web programming to mobile devices and scaling the Firefox mobile operating system.