Apple is losing Jeff Wilcox, its lead silicon designer to rival Intel, eight years after he left Intel to join Apple.

Wilcox hs helped oversee Apple’s development of its own custom silicon, culminating in the company’s M1 line of processors that now power its Mac computers. The M1 shocked the PC industry with its combination of performance and power efficiency, with Intel scrambling to come up with an answer. Scoring Wilcox is a big step in that direction.

Wilcox made the announcement on LinkedIn.

After an amazing eight years I have decided to leave Apple and pursue another opportunity. It has been an incredible ride and I could not be prouder of all we accomplished during my time there, culminating in the Apple SIlicon transition with the M1, M1 Pro and M1 Max SOCs and systems. I will dearly miss all of my Apple colleagues and friends, but I am looking forward to the next journey which will start at the first of the year. More to come!

He later posted about taking the job at Intel, where he will help lead the company’s system-on-chip (SOC) design.

I’m pleased to share that I have started a new position as Intel Fellow, Design Engineering Group CTO, Client SoC Architecture at Intel Corporation. I could not be more thrilled to be back working with the amazing teams there to help create groundbreaking SOCs. Great things are ahead!

There has been no word yet on who will replace Wilcox at Apple.