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post-training

Everything on Ground Truth tagged “post-training” — 6 items.

Direct Preference Optimization: skipping the reward model entirely Lesson

Direct Preference Optimization trains a language model on human preference pairs without ever building a separate reward model or running reinforcement learning, by showing mathematically that the model can serve as its own reward function.

Z.ai changed only the post-training, and the model learned to find exploits News

Z.ai released GLM-5.3 on August 14 using the same base model as GLM-5.2, with every gain coming from post-training, and the largest jump was in finding and exploiting software vulnerabilities.

A model improved itself by training only where it disagreed with itself News

U-OPSD drops the teacher entirely: it samples several attempts, takes a majority vote as a stand-in answer, then trains only on the attempts that disagreed with that vote, matching or beating methods that use real ground-truth labels.

Grafting a Verified Solution Cache Lets a Frozen Model Skip Fine-Tuning Entirely News

A new paper shows a frozen small language model's accuracy on a hard math test can jump from 80.0% to 93.3% simply by grafting a byte-exact cache of verified solutions into it, with no weight changes at all.

Qwen used human-feedback training to make its image AI follow directions better News

A new recipe applies the same reinforcement-learning approach that polished chatbots to an image generator, then merges separate skill models into one - improving how faithfully it follows prompts and edits.

SLAI T-Rex Tool

The public workflow behind a full-parameter Ascend post-training run on a DeepSeek-V4-family model: FP8-to-BF16-to-Megatron checkpoint conversion, launch templates, and inspectable data-construction pipelines for continued pre-training and supervised fine-tuning. The production engine and custom kernels are withheld.