A startup just raised two billion dollars at seed to let you customize cutting-edge AI models with four lines of Python on your laptop. Thinking Machines Lab's new platform Tinker handles all the nightmare distributed training infrastructure while you write straightforward code, using a technique called LoRA that cuts compute costs by a third compared to traditional fine-tuning. Led by former OpenAI CTO Mira Murati, the company hit a twelve billion dollar valuation out of the gate because they're solving the problem every business hits: general AI models work great in demos but fall apart the second you need them to understand your actual terminology and workflows.