Andrey Karpaty, Tesla’s director of artificial intelligence and head of the Autopilot program, resigned from his post after a four-month leave.

“It’s been a great pleasure helping Tesla achieve its goals over the past five years, and the decision to part ways is difficult,” said the engineer.

Karpaty did not mention his plans for the future.

“I hope to spend more time rethinking my long-standing passion for technical work in artificial intelligence, open source, and education,” he said.

Karpathy’s resignation came amid a massive downsizing at Tesla. The company had previously laid off more than 200 Autopilot employees and closed its San Mateo, California office. In total, the automaker plans to lay off up to 10% of workers.

Prior to joining Tesla, Karpathy was a research fellow in the OpenAI deep learning program specializing in computer vision and generative modeling.

In addition to him, Chris Rollins, senior software manager in Tesla’s energy division, and Kristen Kavanaugh, director of diversity and inclusion, have stepped down.

Recall that in March, the electric car maker included artificial intelligence in the company’s long-term development plan.

In December, Elon Musk said that Tesla robots would prevent the collapse of civilization.