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What happens after LLM pre-training?

This map explains the post-training pipeline: supervised fine-tuning, preference data, reward modelling, RLHF, DPO, PPO, GRPO, RLVR, evaluation, and where extra compute is going.

Sources and datesPublished April 2026. This interactive reference explains concepts; its vendor comparisons, market estimates, and purchasing examples are historical and have not received a complete current-source review. Check the original vendor or official source before acting on a specification, price, or legal statement.

Concept corrections, 26 September 2026. Sources: DPO paper · InstructGPT paper · DeepSeek-R1 paper · PPO paper · Reward hacking paper · GPT-4 technical report.

Additional method references: Constitutional AI paper · verl documentation · NeMo RL documentation.