Tinker
Thinking Machines Lab
Managed fine-tuning API with low-level control over the training loop.
Tinker is Thinking Machines Lab's training API for fine-tuning open-weight LLMs. It exposes low-level primitives — forward_backward, optim_step, sample — so researchers keep full control of data and algorithms while the service handles distributed GPU scheduling and failure recovery. LoRA-based runs cover models from small Llamas up to large mixture-of-experts like Qwen-235B and Kimi K2, and trained weights can be downloaded.
Worth knowing
The debut product of Thinking Machines Lab, the startup founded by ex-OpenAI CTO Mira Murati; launched October 2025.
- fine-tuning
- lora
- post-training
- research
- +1