Thinking Machines' Tinker: LoRA based LLM fine-tuning API

**Thinking Machines** recently raised **$2 billion** without shipping a product until now, launching their first product **Tinker**, a managed service API for fine-tuning large and mixture-of-experts models like **Qwen-235B-A22B** using **LoRA** for cost-efficient training. The Tinker API offers low-level primitives for post-training methods and is supported by an open-source **Tinker Cookbook** library. Influential AI figures like **Andrej Karpathy** and **Lilian Weng** praised its design for reducing complexity and boosting research productivity. Meanwhile, **OpenAI** launched **Sora 2**, a video+audio model integrated into their consumer social app, sparking viral engagement and concerns over misuse and content moderation. Sam Altman emphasized the product's dual focus on delight and revenue alongside AGI research.