Cursor admits that its new coding model was built on top of Moonshot AI’s Kimi

AI coding company Cursor launched a new version this week called Composer 2, which it said to be promoted such as providing “demarcation intelligence.”

However, user X is posting under the name Fynn he soon said that Author 2 was “just Kimi 2.5” is an additional motivational lesson – Kimi 2.5 to be An open source model has recently been released by Moonshot AIa Chinese company backed by Alibaba and HongShan (formerly Sequoia China).

As proof, Fynn pointed to a code that seemed to show Kimi as an example.

“(A)n’t even mentioning the model’s name,” he scoffed.

It was a surprising revelation, since Cursor is the highest-grossing startup in the US raised a $2.3 billion round last fall at a cost of $ 29.3 billion, and it is is expected to exceed $2 billion in annual revenue. Also, the company did not mention anything about Moonshot AI or Kimi in its announcement.

However, Cursor’s vice president of programming education Lee Robinson soon agreed“Yes, Writer 2 started with open source!” But he said, “Only ~1/4 of the money spent in the finals came from the rest, the rest came from our education.” As a result, he said Composer 2’s performance on various benchmarks is “significantly different” from Kimi’s.

Robinson also insisted that Kimi’s use of the Cursor was in line with his license, a point that Kimi’s account on X reiterated. Next post thanks to Cursorwhile it said Cursor used Kimi “as part of an official commercial agreement” with Fireworks AI.

“We are proud to see the Kimi-k2.5 providing the foundation,” said Kimi. “Seeing our model successfully integrated through Cursor’s ongoing training & advanced RL training is an open source we’re excited to support.”

So why not accept Kimi first? Beyond the potential embarrassment of not building a prototype from scratch, building on top of China’s model can be difficult right now, with the so-called “arms race” for AI often being developed. the current war between the United States and China. (See, for example, Silicon Valley’s The fear is felt after the Chinese company DeepSeek released a competitive version at the beginning of last year.)

Cursor co-founder Aman Sanger he agreed“It was remiss not to mention Kimi’s background in our blog from the beginning.