Sebastian Raschka publishes a full build-your-own reasoning model course

Raschka published eight coding lectures, about 11 hours, that build a reasoning model from a pre-trained LLM in PyTorch: evaluation, inference-time scaling with sampling and self-consistency, scoring and self-refinement, a GRPO implementation for RLVR with clipping and KL terms, and distillation into a smaller model. The post opens with a section on how reasoning models sit inside an agent harness.