Repo0: Design-Driven Zero-to-All Code Generation

Summary

Existing code generation systems often assume a predefined repository architecture, which fails in zero-to-all code generation where an agent must build a complete software project from natural-language requirements while maintaining modular architecture. We present Repo0, a continuous structural evolution framework that maintains an explicit architectural state as a Dual-Directed-Acyclic-Graph (Dual-DAG), combining requirement-level and component-level DAGs with alignment. Starting from requirements, it iteratively evolves component boundaries via structural actions guided by modularity metrics until convergence, then uses the converged architecture for test-driven code generation. Evaluated on six real-world repositories from RepoCraft using GPT-5 mini and DeepSeek V3.2, Repo0 achieves the highest Functionality Coverage and Pass Rate, improving over the strongest baseline RPG by up to 20.08 and 29.74 percentage points, respectively. Ablations and structural-evolution analyses confirm the importance of the Dual-DAG state, modularity-guided evolution, and explicit convergence.