Building Claude Code with Boris Cherny
Boris Cherny on The Pragmatic Engineer: “Claude Code's 'agentic search' is really just glob and grep, and it outperformed RAG. The team tried several approaches to make agentic search better: local vector databases, recursive model-based indexing, and other fancy approaches. All had downsides (stale indexes, permission complexity). Plain glob and grep, driven by the model, beat everything. This approach was inspired by how Boris observed engineers at Instagram searched code when the click-to-definition functionality in Meta's in-house coding editor was broken.”