Tesla has officially laid off Andrej Karpathy, its director of AI and leader of Autopilot's vision team, who was hired five years ago.

The possibility of Karpathy returning fueled widespread speculation after he took a four-month leave of absence.

Karparthy wrote on Wednesday afternoon, “It has been an honor and a hard decision for me to leave Tesla after five years of helping it reach its goals.

Throughout that time, Autopilot expanded from lane keeping to city streets, and I hope the strong Autopilot team will continue that trend.

Adding that he is looking forward to spending more time 'revisiting my long-term passions around technology, Open Source, and education,' Karpathy said he had no concrete plans for the future.

Karpathy is considering investing in venture capital, according to sources previously quoted by TechCrunch.

A California regulatory filing indicates that Tesla is laying off 229 employees in its Autopilot team and closing its San Mateo, California office, where they worked as data annotation employees.

Previously, Karpathy worked at Elon Musk's OpenAI, an artificial intelligence nonprofit. One of the most respected, deep learning courses taught at Stanford University was developed by him, and he has an extensive background in AI-related fields. 

Tesla's role, in which he developed a computer vision system for the Autopilot advanced driver assistance system, was closely related to his dissertation.

A neural network was used in Karpathy's dissertation to identify discrete and specific items within an image, label them in natural language and then report to the user the findings.  A system that works in reverse was also developed as part of it.