Cursor officially confirms Kimi K2.5 as the base, Dark Side of the Moon: authorized commercial collaboration

Gate News, March 21 — According to 1M AI News monitoring, the official account @Kimi_Moonshot congratulated Cursor on the release of Composer 2 and explained that Cursor accesses Kimi K2.5 through Fireworks AI-hosted RL and inference platforms, which is an authorized commercial partnership. Cursor co-founder Aman Sanger and Vice President of Developer Education Lee Robinson later publicly confirmed the source of the base model and disclosed technical details. Sanger stated that the team evaluated multiple bases for perplexity, and Kimi K2.5 proved to be the strongest. They then continued pre-training and scaled up to four times the computational power for reinforcement learning, deploying via Fireworks AI’s inference and RL sampler. Robinson added that about one-quarter of the computational power in the final model comes from the base, with the remaining three-quarters from Cursor’s own training. Both founders admitted that not mentioning the Kimi base in their blog post was a mistake and said they would specify the source of the base model in the next release. Previously, Elon Musk responded “Yeah, it’s Kimi 2.5” to a related discussion post, further amplifying the topic’s popularity.