Introducing the v0 composite model family

This post details the composite model architecture behind Vercel's v0 AI models, combining RAG, LLMs, and a custom streaming post-processing model for improved code generation quality. It explains the pre-processing steps, the use of state-of-the-art base models (including Quick Edit optimization for smaller changes), and the custom AutoFix model trained with Fireworks AI using RFT for error correction. Performance benchmarks show v0 models substantially outperform their base model counterparts in error-free generation rates, and the AutoFix model achieves high error-free output rates with significantly faster character processing speeds compared to other models.