Elon Musk is confronting growing challenges at his artificial intelligence venture, xAI, acknowledging that the startup “was not built right first time around” and is now being reconstructed “from the foundations up.” The candid admission comes less than six weeks after Musk merged xAI with SpaceX in a deal valuing the combined enterprise at $1.25 trillion.

Musk shared the update on X, the social media platform he acquired through xAI last year, following the departures of several of the company’s co-founders. Most recently, Zihang Dai and Guodong Zhang reportedly left the company, adding to a string of exits that began last month. Influential AI researcher Jimmy Ba announced his departure via X, expressing gratitude for having helped co-found the company. Tony Wu and Toby Pohlen had also left in preceding months.

The departures leave Musk with only two of the original 2023 founding team members still at the helm. The reshuffling comes at a critical time for SpaceX, which is preparing for a potential initial public offering (IPO) this year that could set a record for the aerospace sector.

xAI has not been short of financial backing. In February, Tesla confirmed a $2 billion investment in the AI startup, part of a broader $20 billion funding round previously announced. The merger between SpaceX and xAI last month valued the reusable rocket company at $1 trillion and xAI itself at $250 billion, according to documents reviewed by CNBC.

The restructuring effort also coincides with a push to strengthen technical talent. SpaceX recently hired two programmers, Andrew Milich and Jason Ginsberg, from the AI coding startup Cursor. However, according to the Financial Times, Musk has also ordered a round of job cuts after witnessing rapid advances in coding tools from competitors such as OpenAI and Anthropic.

“Many talented people over the past few years were declined an offer or even an interview @xAI,” Musk wrote on X early Friday. He added that he and Baris Akis, responsible for engineering talent at xAI, are reviewing the company’s interview history and reaching out to promising candidates previously passed over.

The talent challenges are compounded by controversies surrounding xAI’s AI chatbot and image generator, Grok. The platform has drawn government scrutiny in multiple countries after being used to generate non-consensual sexual images, including deepfake content involving real adults and children. Despite this, Grok has secured U.S. government contracts under the Trump administration from the Defense Department and the General Services Administration.

On the infrastructure side, xAI has been investing billions in power and data centers, particularly around Memphis, Tennessee, and recently received a permit in Mississippi for one of the region’s largest natural gas-powered plants to support its data operations.

The company maintains close ties with Tesla, Musk’s primary source of liquid wealth. Tesla is integrating Grok into vehicle infotainment and navigation systems, employing its models in the development of Optimus humanoid robots, and supplying hundreds of millions of dollars’ worth of backup batteries for xAI’s data centers.

Musk and xAI did not immediately respond to requests for comment.