Mozilla chief technology officer Andreas Gal is leaving the firm to found a mysterious Internet of Things (IoT) startup.
Gal announced the move in a public statement, but offered few details on the specifics of his new venture.
"I am departing Mozilla to create a new venture in the IoT space, an open field that presents many of the types of challenges and opportunities that drive our passion for the web," he said.
"I feel deeply humbled and honoured that I had the chance to be part of such an amazing and passionate group of people for many years, building together the web we want.
"I leave with fond memories and great respect for this organisation and the people who build it each day. It has been a great honour to be your colleague and friend."
Gal was a key player at Mozilla and spearheaded several initiatives during his seven-year tenure at the firm, including Firefox OS.
Firefox OS is an open-source platform designed for emerging markets made entirely using open web standards.
The OS has received support from numerous hardware manufacturers, including Alcatel and ZTE, since launching in 2013.
A report on CNET said that the startup will continue Gal's work on Firefox OS and "repurpose the hardware and lower-level software from the smartphone world into the foundational layers of IoT products".
Prior to Mozilla, Gal was a project scientist at the University of California's Secure Systems and Languages Laboratory. He has a PhD in Computer Science from the University of California with a focus on secure systems, type-safe languages, dynamic compilation and virtual machines.
IoT is a growing market being targeted by technology companies. Google launched the IoT-focused Brillo platform and operating system at its I/O developer conference in May alongside Android M.
Not-for-profit startup support centre Digital Catapult listed IoT as a key focus area in April.
However, despite the obvious interest in the IoT, concerns around security have hampered growth.
Representatives from firms including Schneider Electric, ABB, Osram and Philips moved to downplay the concerns during a roundtable hosted by Voltimum in May.
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